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Versions: (draft-jinmei-ipv6-rfc2462bis) 00 01 02 03 04 05 06 07 08 RFC 4862
IETF IPv6 Working Group                                       S. Thomson
Internet-Draft                                                     Cisco
Expires: December 16, 2004                                     T. Narten
T. Jinmei
IPv6 Stateless Address Autoconfiguration
draft-ietf-ipv6-rfc2462bis-02.txt
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Task Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.
time. It is inappropriate to use Internet-Drafts as reference
The list of current Internet-Drafts can be accessed at http://
www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
This Internet-Draft will expire on December 16, 2004.
Copyright (C) The Internet Society (2004). All Rights Reserved.
This document specifies the steps a host takes in deciding how to
autoconfigure its interfaces in IP version 6. The autoconfiguration
process includes creating a link-local address and verifying its
uniqueness on a link, determining what information can be
autoconfigured (addresses, other information, or both), and in the
case of addresses, whether they can be obtained through the stateless
mechanism, the stateful mechanism, or both. This document defines the
process for generating a link-local address, the process for
generating global addresses via stateless address autoconfiguration,
Thomson, et al.        Expires December 16, 2004                [Page 1]
Internet-Draft    IPv6 Stateless Address Autoconfiguration     June 2004
and the Duplicate Address Detection procedure. The details of
autoconfiguration using the stateful protocol is specified in RFC
3315 and RFC 3736.
1.    Introduction . . . . . . . . . . . . . . . . . . . . . . . .  3
2.    TERMINOLOGY  . . . . . . . . . . . . . . . . . . . . . . . .  5
2.1   Requirements . . . . . . . . . . . . . . . . . . . . . . . .  7
3.    DESIGN GOALS . . . . . . . . . . . . . . . . . . . . . . . .  7
4.    PROTOCOL OVERVIEW  . . . . . . . . . . . . . . . . . . . . .  8
4.1   Site Renumbering . . . . . . . . . . . . . . . . . . . . . . 10
5.    PROTOCOL SPECIFICATION . . . . . . . . . . . . . . . . . . . 11
5.1   Node Configuration Variables . . . . . . . . . . . . . . . . 11
5.2   Autoconfiguration-Related Structures . . . . . . . . . . . . 12
5.3   Creation of Link-Local Addresses . . . . . . . . . . . . . . 12
5.4   Duplicate Address Detection  . . . . . . . . . . . . . . . . 13
5.4.1 Message Validation . . . . . . . . . . . . . . . . . . . . . 14
5.4.2 Sending Neighbor Solicitation Messages . . . . . . . . . . . 14
5.4.3 Receiving Neighbor Solicitation Messages . . . . . . . . . . 15
5.4.4 Receiving Neighbor Advertisement Messages  . . . . . . . . . 16
5.4.5 When Duplicate Address Detection Fails . . . . . . . . . . . 17
5.5   Creation of Global Addresses . . . . . . . . . . . . . . . . 17
5.5.1 Soliciting Router Advertisements . . . . . . . . . . . . . . 17
5.5.2 Absence of Router Advertisements . . . . . . . . . . . . . . 17
5.5.3 Router Advertisement Processing  . . . . . . . . . . . . . . 18
5.5.4 Address Lifetime Expiry  . . . . . . . . . . . . . . . . . . 20
5.6   Configuration Consistency  . . . . . . . . . . . . . . . . . 21
5.7   Retaining Configured Addresses for Stability . . . . . . . . 21
6.    SECURITY CONSIDERATIONS  . . . . . . . . . . . . . . . . . . 21
7.    IANA CONSIDERATIONS  . . . . . . . . . . . . . . . . . . . . 22
8.    Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 22
Normative References . . . . . . . . . . . . . . . . . . . . 22
Informative References . . . . . . . . . . . . . . . . . . . 23
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 23
A.    LOOPBACK SUPPRESSION & DUPLICATE ADDRESS DETECTION . . . . . 24
B.    CHANGES SINCE RFC 1971 . . . . . . . . . . . . . . . . . . . 25
C.    CHANGE HISTORY . . . . . . . . . . . . . . . . . . . . . . . 26
Intellectual Property and Copyright Statements . . . . . . . 29
3315 [6] and RFC 3736 [7].
IPv6 defines both a stateful and stateless address autoconfiguration
mechanism. Stateless autoconfiguration requires no manual
configuration of hosts, minimal (if any) configuration of routers,
and no additional servers.  The stateless mechanism allows a host to
generate its own addresses using a combination of locally available
information and information advertised by routers. Routers advertise
prefixes that identify the subnet(s) associated with a link, while
hosts generate an "interface identifier" that uniquely identifies an
interface on a subnet. An address is formed by combining the two. In
the absence of routers, a host can only generate link-local
addresses. However, link-local addresses are sufficient for allowing
communication among nodes attached to the same link.
In the stateful autoconfiguration model, hosts obtain interface
addresses and/or configuration information and parameters from a
DHCPv6 server. Servers maintain a database that keeps track of which
addresses have been assigned to which hosts. The stateful
autoconfiguration protocol allows hosts to obtain addresses, other
configuration information or both from a server. Stateless and
stateful autoconfiguration complement each other. For example, a host
can use stateless autoconfiguration to configure its own addresses,
but use stateful autoconfiguration to obtain other information.
To obtain other configuration information without configuring
addresses in the stateful autoconfiguration model, a subset of DHCPv6
will be used [7]. While the model is called "stateful" here in order
to highlight the contrast to the stateless protocol defined in this
document, the intended protocol is also defined to work in a
stateless fashion. This is based on a result, through operational
experiments, that all known "other" configuration information can be
managed by a stateless server, that is, a server that does not
maintain state of each client that the server provides with the
configuration information.
The stateless approach is used when a site is not particularly
concerned with the exact addresses hosts use, so long as they are
unique and properly routable. The stateful approach is used when a
site requires tighter control over exact address assignments. Both
stateful and stateless address autoconfiguration may be used
simultaneously. The site administrator specifies which type of
autoconfiguration is available through the setting of appropriate
fields in Router Advertisement messages [5].
IPv6 addresses are leased to an interface for a fixed (possibly
infinite) length of time. Each address has an associated lifetime
that indicates how long the address is bound to an interface. When a
lifetime expires, the binding (and address) become invalid and the
address may be reassigned to another interface elsewhere in the
Internet. To handle the expiration of address bindings gracefully, an
address goes through two distinct phases while assigned to an
interface. Initially, an address is "preferred", meaning that its use
in arbitrary communication is unrestricted. Later, an address becomes
"deprecated" in anticipation that its current interface binding will
become invalid. While in a deprecated state, the use of an address is
discouraged, but not strictly forbidden.  New communication (e.g.,
the opening of a new TCP connection) should use a preferred address
when possible.  A deprecated address should be used only by
applications that have been using it and would have difficulty
switching to another address without a service disruption.
To ensure that all configured addresses are likely to be unique on a
given link, nodes run a "duplicate address detection" algorithm on
addresses before assigning them to an interface.  The Duplicate
Address Detection algorithm is performed on all addresses,
independent of whether they are obtained via stateless or stateful
autoconfiguration. This document defines the Duplicate Address
Detection algorithm.
The autoconfiguration process specified in this document applies only
to hosts and not routers. Since host autoconfiguration uses
information advertised by routers, routers will need to be configured
by some other means. However, it is expected that routers will
generate link-local addresses using the mechanism described in this
document. In addition, routers are expected to successfully pass the
Duplicate Address Detection procedure described in this document on
all addresses prior to assigning them to an interface.
Section 2 provides definitions for terminology used throughout this
document. Section 3 describes the design goals that lead to the
current autoconfiguration procedure. Section 4 provides an overview
of the protocol, while Section 5 describes the protocol in detail.
IP - Internet Protocol Version 6. The terms IPv4 and IPv6 are used
only in contexts where necessary to avoid ambiguity.
node - a device that implements IP.
router - a node that forwards IP packets not explicitly addressed to
host - any node that is not a router.
upper layer - a protocol layer immediately above IP. Examples are
transport protocols such as TCP and UDP, control protocols such as
ICMP, routing protocols such as OSPF, and internet or lower-layer
protocols being "tunneled" over (i.e., encapsulated in) IP such as
IPX, AppleTalk, or IP itself.
link - a communication facility or medium over which nodes can
communicate at the link layer, i.e., the layer immediately below
IP.  Examples are Ethernets (simple or bridged); PPP links; X.25,
Frame Relay, or ATM networks; and internet (or higher) layer
interface - a node's attachment to a link.
packet - an IP header plus payload.
address - an IP-layer identifier for an interface or a set of
unicast address - an identifier for a single interface. A packet sent
to a unicast address is delivered to the interface identified by
that address.
multicast address - an identifier for a set of interfaces (typically
belonging to different nodes). A packet sent to a multicast
address is delivered to all interfaces identified by that address.
anycast address - an identifier for a set of interfaces (typically
belonging to different nodes).  A packet sent to an anycast
address is delivered to one of the interfaces identified by that
address (the "nearest" one, according to the routing protocol's
measure of distance). See the IPv6 addressing architecture [4].
solicited-node multicast address - a multicast address to which
Neighbor Solicitation messages are sent. The algorithm for
computing the address is given in RFC 2461 [5].
link-layer address - a link-layer identifier for an interface.
Examples include IEEE 802 addresses for Ethernet links and E.164
addresses for ISDN links.
link-local address - an address having link-only scope that can be
used to reach neighboring nodes attached to the same link.  All
interfaces have a link-local unicast address.
global address - an address with unlimited scope.
communication - any packet exchange among nodes that requires that
the address of each node used in the exchange remain the same for
the duration of the packet exchange.  Examples are a TCP
connection or a UDP request-response.
tentative address - an address whose uniqueness on a link is being
verified, prior to its assignment to an interface.  A tentative
address is not considered assigned to an interface in the usual
sense. An interface discards received packets addressed to a
tentative address, but accepts Neighbor Discovery packets related
to Duplicate Address Detection for the tentative address.
preferred address - an address assigned to an interface whose use by
upper layer protocols is unrestricted. Preferred addresses may be
used as the source (or destination) address of packets sent from
(or to) the interface.
deprecated address - An address assigned to an interface whose use is
discouraged, but not forbidden.  A deprecated address should no
longer be used as a source address in new communications, but
packets sent from or to deprecated addresses are delivered as
expected.  A deprecated address may continue to be used as a
source address in communications where switching to a preferred
address causes hardship to a specific upper-layer activity (e.g.,
an existing TCP connection).
valid address - a preferred or deprecated address. A valid address
may appear as the source or destination address of a packet, and
the internet routing system is expected to deliver packets sent to
a valid address to their intended recipients.
invalid address - an address that is not assigned to any interface. A
valid address becomes invalid when its valid lifetime expires.
Invalid addresses should not appear as the destination or source
address of a packet. In the former case, the internet routing
system will be unable to deliver the packet, in the latter case
the recipient of the packet will be unable to respond to it.
preferred lifetime - the length of time that a valid address is
preferred (i.e., the time until deprecation). When the preferred
lifetime expires, the address becomes deprecated.
valid lifetime - the length of time an address remains in the valid
state (i.e., the time until invalidation). The valid lifetime must
be greater than or equal to the preferred lifetime.  When the
valid lifetime expires, the address becomes invalid.
interface identifier - a link-dependent identifier for an interface
that is (at least) unique per link [4]. Stateless address
autoconfiguration combines an interface identifier with a prefix
to form an address. From address autoconfiguration's perspective,
an interface identifier is a bit string of known length. The exact
length of an interface identifier and the way it is created is
defined in a separate link-type specific document that covers
issues related to the transmission of IP over a particular link
type (e.g., IPv6 over Ethernet [2]). Note that the address
architecture [4] also defines the length of the interface
identifiers for some set of addresses, but the two sets of
definitions must be consistent. In many cases, the identifier will
be derived from the interface's link-layer address.
2.1 Requirements
document, are to be interpreted as described in RFC 2119 [3].
3. DESIGN GOALS
Stateless autoconfiguration is designed with the following goals in
mind:
o  Manual configuration of individual machines before connecting them
to the network should not be required. Consequently, a mechanism
is needed that allows a host to obtain or create unique addresses
for each of its interfaces. Address autoconfiguration assumes that
each interface can provide a unique identifier for that interface
(i.e., an "interface identifier").  In the simplest case, an
interface identifier consists of the interface's link-layer
address. An interface identifier can be combined with a prefix to
form an address.
o  Small sites consisting of a set of machines attached to a single
link should not require the presence of a stateful server or
router as a prerequisite for communicating.  Plug-and-play
communication is achieved through the use of link-local addresses.
Link-local addresses have a well-known prefix that identifies the
(single) shared link to which a set of nodes attach. A host forms
a link-local address by appending its interface identifier to the
o  A large site with multiple networks and routers should not require
the presence of a stateful address configuration server. In order
to generate global addresses, hosts must determine the prefixes
that identify the subnets to which they attach.  Routers generate
periodic Router Advertisements that include options listing the
set of active prefixes on a link.
o  Address configuration should facilitate the graceful renumbering
of a site's machines. For example, a site may wish to renumber all
of its nodes when it switches to a new network service provider.
Renumbering is achieved through the leasing of addresses to
interfaces and the assignment of multiple addresses to the same
interface.  Lease lifetimes provide the mechanism through which a
site phases out old prefixes.  The assignment of multiple
addresses to an interface provides for a transition period during
which both a new address and the one being phased out work
simultaneously.
o  System administrators need the ability to specify whether
stateless autoconfiguration, stateful autoconfiguration, or both
are available. Router Advertisements include flags specifying
which mechanisms a host can use.
This section provides an overview of the typical steps that take
place when an interface autoconfigures itself.  Autoconfiguration is
performed only on multicast-capable links and begins when a
multicast-capable interface is enabled, e.g., during system startup.
Nodes (both hosts and routers) begin the autoconfiguration process by
generating a link-local address for the interface. A link-local
address is formed by appending the interface's identifier to the
well-known link-local prefix.
Before the link-local address can be assigned to an interface and
used, however, a node must attempt to verify that this "tentative"
address is not already in use by another node on the link.
Specifically, it sends a Neighbor Solicitation message containing the
tentative address as the target. If another node is already using
that address, it will return a Neighbor Advertisement saying so. If
another node is also attempting to use the same address, it will send
a Neighbor Solicitation for the target as well. The exact number of
times the Neighbor Solicitation is (re)transmitted and the delay time
between consecutive solicitations is link-specific and may be set by
system management.
If a node determines that its tentative link-local address is not
unique, autoconfiguration stops and manual configuration of the
interface is required.  To simplify recovery in this case, it should
be possible for an administrator to supply an alternate interface
identifier that overrides the default identifier in such a way that
the autoconfiguration mechanism can then be applied using the new
(presumably unique) interface identifier.  Alternatively, link-local
and other addresses will need to be configured manually.
Once a node ascertains that its tentative link-local address is
unique, it assigns the address to the interface. At this point, the
node has IP-level connectivity with neighboring nodes.  The remaining
autoconfiguration steps are performed only by hosts; the
(auto)configuration of routers is beyond the scope of this document.
The next phase of autoconfiguration involves obtaining a Router
Advertisement or determining that no routers are present. If routers
are present, they will send Router Advertisements that specify what
sort of autoconfiguration a host can do. Note that stateful
autoconfiguration may still be available even if no routers are
Routers send Router Advertisements periodically, but the delay
between successive advertisements will generally be longer than a
host performing autoconfiguration will want to wait [5]. To obtain an
advertisement quickly, a host sends one or more Router Solicitations
to the all-routers multicast group. Router Advertisements contain two
flags indicating what type of stateful autoconfiguration (if any) is
available. A "managed address configuration (M)" flag indicates
whether hosts can use stateful autoconfiguration [6] to obtain
addresses. An "other stateful configuration (O)" flag indicates
additional information (excluding addresses).
The details of how a host may use the M flags, including any use of
the "on" and "off" transitions for this flag, to control the use of
the stateful protocol for address assignment will be described in a
separate document. Similarly, the details of how a host may use the O
flags, including any use of the "on" and "off" transitions for this
flag, to control the use of the stateful protocol for getting other
configuration information will be described in a separate document.
Router Advertisements also contain zero or more Prefix Information
options that contain information used by stateless address
autoconfiguration to generate global addresses.  It should be noted
that the stateless and stateful address autoconfiguration fields in
Router Advertisements are processed independently of one another, and
a host may use both stateful and stateless address autoconfiguration
simultaneously.  One Prefix Information option field, the "autonomous
address-configuration flag", indicates whether or not the option even
applies to stateless autoconfiguration.  If it does, additional
option fields contain a subnet prefix together with lifetime values
indicating how long addresses created from the prefix remain
preferred and valid.
Because routers generate Router Advertisements periodically, hosts
will continually receive new advertisements. Hosts process the
information contained in each advertisement as described above,
adding to and refreshing information received in previous
For safety, all addresses must be tested for uniqueness prior to
their assignment to an interface. The test should individually be
performed on all addresses obtained manually, via stateless address
autoconfiguration, or via stateful address autoconfiguration. To
accommodate sites that believe the overhead of performing Duplicate
Address Detection outweighs its benefits, the use of Duplicate
Address Detection can be disabled through the administrative setting
of a per-interface configuration flag.
To speed the autoconfiguration process, a host may generate its
link-local address (and verify its uniqueness) in parallel with
waiting for a Router Advertisement. Because a router may delay
responding to a Router Solicitation for a few seconds, the total time
needed to complete autoconfiguration can be significantly longer if
the two steps are done serially.
4.1 Site Renumbering
Address leasing facilitates site renumbering by providing a mechanism
to time-out addresses assigned to interfaces in hosts.  At present,
upper layer protocols such as TCP provide no support for changing
end-point addresses while a connection is open. If an end-point
address becomes invalid, existing connections break and all
communication to the invalid address fails.  Even when applications
use UDP as a transport protocol, addresses must generally remain the
same during a packet exchange.
Dividing valid addresses into preferred and deprecated categories
provides a way of indicating to upper layers that a valid address may
become invalid shortly and that future communication using the
Thomson, et al.        Expires December 16, 2004               [Page 10]
address will fail, should the address's valid lifetime expire before
communication ends.  To avoid this scenario, higher layers should use
a preferred address (assuming one of sufficient scope exists) to
increase the likelihood that an address will remain valid for the
duration of the communication.  It is up to system administrators to
set appropriate prefix lifetimes in order to minimize the impact of
failed communication when renumbering takes place.  The deprecation
period should be long enough that most, if not all, communications
are using the new address at the time an address becomes invalid.
The IP layer is expected to provide a means for upper layers
(including applications) to select the most appropriate source
address given a particular destination and possibly other
constraints.  An application may choose to select the source address
itself before starting a new communication or may leave the address
unspecified, in which case the upper networking layers will use the
mechanism provided by the IP layer to choose a suitable address on
the application's behalf.
Detailed address selection rules are beyond the scope of this
5. PROTOCOL SPECIFICATION
Autoconfiguration is performed on a per-interface basis on
multicast-capable interfaces.  For multihomed hosts,
autoconfiguration is performed independently on each interface.
Autoconfiguration applies primarily to hosts, with two exceptions.
Routers are expected to generate a link-local address using the
procedure outlined below. In addition, routers perform Duplicate
Address Detection on all addresses prior to assigning them to an
interface.
5.1 Node Configuration Variables
A node MUST allow the following autoconfiguration-related variable to
be configured by system management for each multicast interface:
DupAddrDetectTransmits
The number of consecutive Neighbor Solicitation messages sent
while performing Duplicate Address Detection on a tentative
address. A value of zero indicates that Duplicate Address
Detection is not performed on tentative addresses. A value of one
indicates a single transmission with no follow up retransmissions.
Default: 1, but may be overridden by a link-type specific value in
the document that covers issues related to the transmission of IP
over a particular link type (e.g., IPv6 over Ethernet [2]).
Autoconfiguration also assumes the presence of the variable
RetransTimer as defined in RFC 2461 [5]. For autoconfiguration
purposes, RetransTimer specifies the delay between consecutive
Neighbor Solicitation transmissions performed during Duplicate
Address Detection (if DupAddrDetectTransmits is greater than 1),
as well as the time a node waits after sending the last Neighbor
Solicitation before ending the Duplicate Address Detection
5.2 Autoconfiguration-Related Structures
Beyond the formation of a link-local address and using Duplicate
Address Detection, how routers (auto)configure their interfaces is
beyond the scope of this document.
A host maintains a list of addresses together with their
corresponding lifetimes. The address list contains both
autoconfigured addresses and those configured manually.
5.3 Creation of Link-Local Addresses
A node forms a link-local address whenever an interface becomes
enabled.  An interface may become enabled after any of the following
-  The interface is initialized at system startup time.
-  The interface is reinitialized after a temporary interface failure
or after being temporarily disabled by system management.
-  The interface attaches to a link for the first time.
-  The interface becomes enabled by system management after having
been administratively disabled.
A link-local address is formed by prepending the well-known link-
local prefix FE80::0 [4] (of appropriate length) to the interface
identifier. If the interface identifier has a length of N bits, the
interface identifier replaces the right-most N zero bits of the
link-local prefix. If the interface identifier is more than 118 bits
in length, autoconfiguration fails and manual configuration is
required. The length of the interface identifier is defined in a
separate link-type specific document, which should also be consistent
with the address architecture [4] (see Section 2). These documents
will carefully define the length so that link-local addresses can be
autoconfigured on the link.
A link-local address has an infinite preferred and valid lifetime; it
is never timed out.
5.4 Duplicate Address Detection
Duplicate Address Detection is performed on unicast addresses prior
to assigning them to an interface whose DupAddrDetectTransmits
variable is greater than zero. Duplicate Address Detection MUST take
place on all unicast addresses, regardless of whether they are
obtained through stateful, stateless or manual configuration, with
the exception of the following cases:
IP - Duplicate Address Detection MUST NOT be performed on anycast
addresses.
IP - Each individual unicast address SHOULD be tested for uniqueness.
Note that there are implementations deployed that only perform
Duplicate Address Detection for the link-local address and skip
the test for the global address using the same interface
identifier as that of the link-local address. Whereas this
document does not invalidate such implementations, this kind of
"optimization" is NOT RECOMMENDED, and new implementations MUST
NOT do that optimization. This optimization came from the
assumption that all of an interface's addresses are generated from
the same identifier. However, the assumption does actually not
stand; new types of addresses have been introduced where the
interface identifiers are not necessarily the same for all unicast
addresses on a single interface [9] [10]. Requiring to perform
Duplicate Address Detection for all unicast addresses will make
the algorithm robust for the current and future such special
interface identifiers.
The procedure for detecting duplicate addresses uses Neighbor
Solicitation and Advertisement messages as described below. If a
duplicate address is discovered during the procedure, the address
cannot be assigned to the interface. If the address is derived from
an interface identifier, a new identifier will need to be assigned to
the interface, or all IP addresses for the interface will need to be
manually configured.  Note that the method for detecting duplicates
is not completely reliable, and it is possible that duplicate
addresses will still exist (e.g., if the link was partitioned while
Duplicate Address Detection was performed).
An address on which the Duplicate Address Detection Procedure is
applied is said to be tentative until the procedure has completed
successfully.  A tentative address is not considered "assigned to an
interface" in the traditional sense. That is, the interface must
accept Neighbor Solicitation and Advertisement messages containing
the tentative address in the Target Address field, but processes such
packets differently from those whose Target Address matches an
address assigned to the interface. Other packets addressed to the
tentative address should be silently discarded. Note that the "other
packets" include Neighbor Solicitation and Advertisement messages to
the tentative address containing the tentative address in the Target
Address field. Such a case should not happen in normal operation,
though, since these messages are multicasted in the Duplicate Address
Detection Procedure.
It should also be noted that Duplicate Address Detection must be
performed prior to assigning an address to an interface in order to
prevent multiple nodes from using the same address simultaneously. If
a node begins using an address in parallel with Duplicate Address
Detection, and another node is already using the address, the node
performing Duplicate Address Detection will erroneously process
traffic intended for the other node, resulting in such possible
negative consequences as the resetting of open TCP connections.
The following subsections describe specific tests a node performs to
verify an address's uniqueness.  An address is considered unique if
none of the tests indicate the presence of a duplicate address within
RetransTimer milliseconds after having sent DupAddrDetectTransmits
Neighbor Solicitations. Once an address is determined to be unique,
it may be assigned to an interface.
5.4.1 Message Validation
A node MUST silently discard any Neighbor Solicitation or
Advertisement message that does not pass the validity checks
specified in RFC 2461 [5]. A Neighbor Solicitation or Advertisement
message that passes these validity checks is called a valid
solicitation or valid advertisement, respectively.
5.4.2 Sending Neighbor Solicitation Messages
Before sending a Neighbor Solicitation, an interface MUST join the
all-nodes multicast address and the solicited-node multicast address
of the tentative address. The former ensures that the node receives
Neighbor Advertisements from other nodes already using the address;
the latter ensures that two nodes attempting to use the same address
simultaneously detect each other's presence.
To check an address, a node sends DupAddrDetectTransmits Neighbor
Solicitations, each separated by RetransTimer milliseconds. The
solicitation's Target Address is set to the address being checked,
the IP source is set to the unspecified address and the IP
destination is set to the solicited-node multicast address of the
target address.
If the Neighbor Solicitation is going to be the first message to be
sent from an interface after interface (re)initialization, the node
SHOULD delay joining the solicited-node multicast address by a random
delay between 0 and MAX_RTR_SOLICITATION_DELAY as specified in RFC
2461 [5]. This serves to alleviate congestion when many nodes start
up on the link at the same time, such as after a power failure, and
may help to avoid race conditions when more than one node is trying
to solicit for the same address at the same time.
Even if the Neighbor Solicitation is not going to be the first
message to be sent, the node SHOULD delay joining the solicited-node
multicast address by a random delay between 0 and
MAX_RTR_SOLICITATION_DELAY if the address being checked is configured
by a router advertisement message sent to a multicast address. The
delay will avoid similar congestion when multiple nodes are going to
configure addresses by receiving a same single multicast router
Note that the delay for joining the multicast address implicitly
means delaying transmission of the corresponding MLD report message
[11]. Since RFC 2710 [11] does not request a random delay to avoid
race conditions, just delaying Neighbor Solicitation would cause
congestion by the MLD report messages. The congestion would then
prevent MLD-snooping switches from working correctly, and, as a
result, prevent Duplicate Address Detection from working. The
requirement to include the delay for the MLD report in this case
avoids this scenario.
In order to improve the robustness of the Duplicate Address Detection
algorithm, an interface MUST receive and process datagrams sent to
the all-nodes multicast address or solicited-node multicast address
of the tentative address while the delaying period. This does not
necessarily conflict with the requirement that joining the multicast
group be delayed. In fact, in some cases it is possible for a node to
start listening to the group during the delay period before MLD
report transmission. It should be noted, however, that in some
link-layer environments, particularly with MLD-snooping switches, no
multicast reception will be available until the MLD report is sent.
5.4.3 Receiving Neighbor Solicitation Messages
On receipt of a valid Neighbor Solicitation message on an interface,
node behavior depends on whether the target address is tentative or
not.  If the target address is not tentative (i.e., it is assigned to
the receiving interface), the solicitation is processed as described
in RFC 2461 [5].  If the target address is tentative, and the source
address is a unicast address, the solicitation's sender is performing
address resolution on the target; the solicitation should be silently
ignored.  Otherwise, processing takes place as described below. In
all cases, a node MUST NOT respond to a Neighbor Solicitation for a
tentative address.
If the source address of the Neighbor Solicitation is the unspecified
address, the solicitation is from a node performing Duplicate Address
Detection. If the solicitation is from another node, the tentative
address is a duplicate and should not be used (by either node). If
the solicitation is from the node itself (because the node loops back
multicast packets), the solicitation does not indicate the presence
of a duplicate address.
Implementor's Note: many interfaces provide a way for upper layers to
selectively enable and disable the looping back of multicast packets.
The details of how such a facility is implemented may prevent
Duplicate Address Detection from working correctly. See the Appendix
A for further discussion.
The following tests identify conditions under which a tentative
address is not unique:
-  If a Neighbor Solicitation for a tentative address is received
prior to having sent one, the tentative address is a duplicate.
This condition occurs when two nodes run Duplicate Address
Detection simultaneously, but transmit initial solicitations at
different times (e.g., by selecting different random delay values
before joining the solicited-node multicast address and
transmitting an initial solicitation).
-  If the actual number of Neighbor Solicitations received exceeds
the number expected based on the loopback semantics (e.g., the
interface does not loopback packet, yet one or more solicitations
was received), the tentative address is a duplicate. This
condition occurs when two nodes run Duplicate Address Detection
simultaneously and transmit solicitations at roughly the same
5.4.4 Receiving Neighbor Advertisement Messages
On receipt of a valid Neighbor Advertisement message on an interface,
matches a unicast or anycast address assigned to the interface.  If
the target address is assigned to the receiving interface, the
solicitation is processed as described in RFC 2461 [5]. If the target
address is tentative, the tentative address is not unique.
5.4.5 When Duplicate Address Detection Fails
A tentative address that is determined to be a duplicate as described
above MUST NOT be assigned to an interface and the node SHOULD log a
system management error. If the address is a link-local address
formed from an interface identifier based on the hardware address
(e.g., EUI-64), the interface SHOULD be disabled. In this case, the
IP address duplication probably means duplicate hardware addresses
are in use, and trying to recover from it by configuring another IP
address will not result in a usable network. In fact, it probably
makes things worse by creating problems that are harder to diagnose
than just shutting down the interface; the user will see a partially
working network where some things work, and other things will not. On
the other hand, if the duplicated link-local address is not formed
from an interface identifier based on the hardware address, the
interface MAY continue to be used.
5.5 Creation of Global Addresses
Global addresses are formed by appending an interface identifier to a
prefix of appropriate length. Prefixes are obtained from Prefix
Information options contained in Router Advertisements. Creation of
global addresses and configuration of other parameters as described
in this section SHOULD be locally configurable. However, the
processing described below MUST be enabled by default.
5.5.1 Soliciting Router Advertisements
Router Advertisements are sent periodically to the all-nodes
multicast address. To obtain an advertisement quickly, a host sends
out Router Solicitations as described in RFC 2461 [5].
5.5.2 Absence of Router Advertisements
Even if a link has no routers, stateful autoconfiguration to obtain
addresses and other configuration information may still be available,
and hosts may want to use the mechanism. From the perspective of
autoconfiguration, a link has no routers if no Router Advertisements
are received after having sent a small number of Router Solicitations
as described in RFC 2461 [5].
Note that it is possible that there is no router on the link in this
sense but there is a node that has the ability to forward packets. In
this case, the forwarding node's address must be manually configured
in hosts to be able to send packets off-link, since the only
mechanism to configure the default router's address automatically is
the one using router advertisements.
5.5.3 Router Advertisement Processing
For each Prefix-Information option in the Router Advertisement:
a) If the Autonomous flag is not set, silently ignore the Prefix
b) If the prefix is the link-local prefix, silently ignore the
c) If the preferred lifetime is greater than the valid lifetime,
silently ignore the Prefix Information option. A node MAY wish to
log a system management error in this case.
d) If the prefix advertised is not equal to the prefix of an address
configured by stateless autoconfiguration already in the list of
addresses associated with the interface (where "equal" means the
two prefix lengths are the same and the first prefix-length bits
of the prefixes are identical), and the Valid Lifetime is not 0,
form an address (and add it to the list) by combining the
advertised prefix with the link's interface identifier as follows:
|            128 - N bits               |       N bits           |
+---------------------------------------+------------------------+
|            link prefix                |  interface identifier  |
+----------------------------------------------------------------+
If the sum of the prefix length and interface identifier length
does not equal 128 bits, the Prefix Information option MUST be
ignored. An implementation MAY wish to log a system management
error in this case. The length of the interface identifier is
defined in a separate link-type specific document, which should
also be consistent with the address architecture [4] (see Section
It is the responsibility of the system administrator to insure
that the lengths of prefixes contained in Router Advertisements
are consistent with the length of interface identifiers for that
link type. It should be noted, however, that this does not mean
the advertised prefix length is meaningless. In fact, the
advertised length has non trivial meaning for on-link
determination in RFC 2461 [5] where the sum of the prefix length
and the interface identifier length may not be equal to 128. Thus,
it should be safe to validate the advertised prefix length here,
in order to detect and avoid a configuration error specifying an
invalid prefix length in the context of address autoconfiguration.
Note that a future revision of the address architecture [4] and a
future link-type specific document, which will still be consistent
with each other, could potentially allow for an interface
identifier of length other than the value defined in the current
documents. Thus, an implementation should not assume a particular
constant. Rather, it should expect any lengths of interface
identifiers.
If an address is formed successfully, the host adds it to the list
of addresses assigned to the interface, initializing its preferred
and valid lifetime values from the Prefix Information option.
e) If the advertised prefix is equal to the prefix of an address
configured by stateless autoconfiguration in the list, the
preferred lifetime of the address is reset to the Preferred
Lifetime in the received advertisement. The specific action to
perform for the valid lifetime of the address depends on the Valid
Lifetime in the received advertisement and the remaining time to
the valid lifetime expiration of the previously autoconfigured
address. We call the remaining time "RemainingLifetime" in the
following discussion:
1.  If the received Valid Lifetime is greater than 2 hours or
greater than RemainingLifetime, set the valid lifetime of the
corresponding address to the advertised Valid Lifetime.
2.  If RemainingLifetime is less than or equal to 2 hours, ignore
the Prefix Information option with regards to the valid
lifetime, unless the Router Advertisement from which this
option was obtained has been authenticated (e.g., via IP
security [1]). If the Router Advertisement was authenticated,
the valid lifetime of the corresponding address should be set
to the Valid Lifetime in the received option.
3.  Otherwise, reset the valid lifetime of the corresponding
address to two hours.
The above rules address a specific denial of service attack in
which a bogus advertisement could contain prefixes with very small
Valid Lifetimes. Without the above rules, a single unauthenticated
advertisement containing bogus Prefix Information options with
short Valid Lifetimes could cause all of a node's addresses to
expire prematurely. The above rules ensure that legitimate
advertisements (which are sent periodically) will "cancel" the
short Valid Lifetimes before they actually take effect.
Note that the preferred lifetime of the corresponding address is
always reset to the Preferred Lifetime in the received Prefix
Information option, regardless of whether the valid lifetime is
also reset or ignored. The difference comes from the fact that the
possible attack for the preferred lifetime is relatively minor.
Additionally, it is even undesirable to ignore the preferred
lifetime when a valid administrator wants to deprecate a
particular address by sending a short preferred lifetime (and the
valid lifetime is ignored by accident).
5.5.4 Address Lifetime Expiry
A preferred address becomes deprecated when its preferred lifetime
expires. A deprecated address SHOULD continue to be used as a source
address in existing communications, but SHOULD NOT be used to
initiate new communications if an alternate (non-deprecated) address
of sufficient scope can easily be used instead.
Note that the feasibility of initiating new communication using a
non-deprecated address may be an application-specific decision, as
only the application may have knowledge about whether the (now)
deprecated address was (or still is) in use by the application. For
example, if an application explicitly specifies the protocol stack to
use a deprecated address as a source address, the protocol stack must
accept that; the application might request it because that IP address
is used for in higher-level communication and there might be a
requirement that the multiple connections in such a grouping use the
same pair of IP addresses.
IP and higher layers (e.g., TCP, UDP) MUST continue to accept and
process datagrams destined to a deprecated address as normal since a
deprecated address is still a valid address for the interface. In the
case of TCP, this means TCP SYN segments sent to a deprecated address
are responded to using the deprecated address as a source address in
the corresponding SYN-ACK (if the connection would otherwise be
allowed).
An implementation MAY prevent any new communication from using a
deprecated address, but system management MUST have the ability to
disable such a facility, and the facility MUST be disabled by
Other subtle cases should also be noted about source address
selection. For example, the above description does not clarify which
address should be used between a deprecated, smaller-scope address
and a non-deprecated, enough scope address. The details of the
address selection including this case are described in RFC 3484 [8]
and beyond the scope of this document.
An address (and its association with an interface) becomes invalid
when its valid lifetime expires.  An invalid address MUST NOT be used
as a source address in outgoing communications and MUST NOT be
recognized as a destination on a receiving interface.
5.6 Configuration Consistency
It is possible for hosts to obtain address information using both
stateless and stateful protocols since both may be enabled at the
same time.  It is also possible that the values of other
configuration parameters such as MTU size and hop limit will be
learned from both Router Advertisements and the stateful
autoconfiguration protocol.  If the same configuration information is
provided by multiple sources, the value of this information should be
consistent. However, it is not considered a fatal error if
information received from multiple sources is inconsistent. Hosts
accept the union of all information received via the stateless and
stateful protocols. If inconsistent information is learned different
sources, the most recently obtained values always have precedence
over information learned earlier.
5.7 Retaining Configured Addresses for Stability
An implementation that has stable storage may want to retain
addresses in the storage when the addresses were acquired using
stateless address autoconfiguration. Assuming the lifetimes used are
reasonable, this technique implies that a temporary outage (less than
the valid lifetime) of a router will never result in the node losing
its global address even if the node were to reboot. When this
technique is used, it should also be noted that the expiration times
of the preferred and valid lifetimes must be retained, in order to
prevent the use of an address after it has become deprecated or
invalid.
Further details on this kind of extension are beyond the scope of
this document.
Stateless address autoconfiguration allows a host to connect to a
network, configure an address and start communicating with other
nodes without ever registering or authenticating itself with the
local site.  Although this allows unauthorized users to connect to
and use a network, the threat is inherently present in the Internet
architecture. Any node with a physical attachment to a network can
generate an address (using a variety of ad hoc techniques) that
provides connectivity.
The use of stateless address autoconfiguration and Duplicate Address
Detection opens up the possibility of several denial of service
attacks. For example, any node can respond to Neighbor Solicitations
for a tentative address, causing the other node to reject the address
as a duplicate. A separate document [12] discusses details about
these attacks. These attacks can be addressed by requiring that
Neighbor Discovery packets be authenticated [1]. However, it should
be noted that [12] points out the use of IP security is not always
feasible depending on network environments.
This document has no actions for IANA.
The authors would like to thank the members of both the IPNG (which
is now IPV6) and ADDRCONF working groups for their input. In
particular, thanks to Jim Bound, Steve Deering, Richard Draves, and
Erik Nordmark.  Thanks also goes to John Gilmore for alerting the WG
of the "0 Lifetime Prefix Advertisement" denial of service attack
vulnerability; this document incorporates changes that address this
A number of people have contributed to identifying issues on a
previous version of this document and to proposing resolutions to the
issues, on which this version is based. In addition to those listed
above, the contributors include Jari Arkko, Brian E Carpenter,
Gregory Daley, Ralph Droms, Christian Huitema, Soohong Daniel Park,
Markku Savela, and Pekka Savola.
Normative References
[1]  Kent, S. and R. Atkinson, "IP Authentication Header", RFC 2402,
[2]  Crawford, M., "A Method for the Transmission of IPv6 Packets
over Ethernet Networks", RFC 2464, December 1998.
[3]  Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", RFC 2119, March 1997.
[4]  Hinden, R. and S. Deering, "Internet Protocol Version 6 (IPv6)
Addressing Architecture", RFC 3513, April 2003.
[5]  Narten, T., Nordmark, E. and W. Simpson, "Neighbor Discovery for
IP Version 6 (IPv6)", RFC 2461, December 1998.
Informative References
[6]   Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C. and M.
Carney, "Dynamic Host Configuration Protocol for IPv6
(DHCPv6)", RFC 3315, July 2003.
[7]   Droms, R., "Stateless Dynamic Host Configuration Protocol
(DHCP) Service for IPv6", RFC 3736, April 2004.
[8]   Draves, R., "Default Address Selection for Internet Protocol
version 6 (IPv6)", RFC 3484, February 2003.
[9]   Narten, T. and R. Draves, "Privacy Extensions for Stateless
Address Autoconfiguration in IPv6", RFC 3041, January 2001.
[10]  Aura, T., "Cryptographically Generated Addresses (CGA)",
draft-ietf-send-cga-06.txt (work in progress), April 2004.
[11]  Deering, S., Fenner, W. and B. Haberman, "Multicast Listener
Discovery (MLD) for IPv6", RFC 2710, October 1999.
[12]  Nikander, P., Kempf, J. and E. Nordmark, "IPv6 Neighbor
Discovery (ND) Trust Models and Threats", RFC 3756, May 2004.
[13]  Deering, S., "Host Extensions for IP Multicasting", RFC 1112,
[14]  IEEE, "Wireless LAN Medium Access Control (MAC) and Physical
Layer (PHY) Specifications", ANSI/IEEE STd 802.11, August 1999.
Susan Thomson
EMail: sethomso@cisco.com
Research Triangle Park, NC  27709-2195
Tatuya Jinmei
Corporate Research & Development Center, Toshiba Corporation
1 Komukai Toshiba-cho, Saiwai-ku
Kawasaki-shi, Kanagawa  212-8582
Phone: +81 44-549-2230
EMail: jinmei@isl.rdc.toshiba.co.jp
Appendix A. LOOPBACK SUPPRESSION & DUPLICATE ADDRESS DETECTION
Determining whether a received multicast solicitation was looped back
to the sender or actually came from another node is implementation-
dependent.  A problematic case occurs when two interfaces attached to
the same link happen to have the same identifier and link-layer
address, and they both send out packets with identical contents at
roughly the same time (e.g., Neighbor Solicitations for a tentative
address as part of Duplicate Address Detection messages). Although a
receiver will receive both packets, it cannot determine which packet
was looped back and which packet came from the other node by simply
comparing packet contents (i.e., the contents are identical). In this
particular case, it is not necessary to know precisely which packet
was looped back and which was sent by another node; if one receives
more solicitations than were sent, the tentative address is a
duplicate. However, the situation may not always be this
straightforward.
The IPv4 multicast specification [13] recommends that the service
interface provide a way for an upper-layer protocol to inhibit local
delivery of packets sent to a multicast group that the sending host
is a member of. Some applications know that there will be no other
group members on the same host, and suppressing loopback prevents
them from having to receive (and discard) the packets they themselves
send out.  A straightforward way to implement this facility is to
disable loopback at the hardware level (if supported by the
hardware), with packets looped back (if requested) by software.  On
interfaces in which the hardware itself suppresses loopbacks, a node
running Duplicate Address Detection simply counts the number of
Neighbor Solicitations received for a tentative address and compares
them with the number expected. If there is a mismatch, the tentative
address is a duplicate.
In those cases where the hardware cannot suppress loopbacks, however,
one possible software heuristic to filter out unwanted loopbacks is
to discard any received packet whose link-layer source address is the
same as the receiving interface's. There is even a link-layer
specification that requires to discard any such packets [14].
Unfortunately, use of that criteria also results in the discarding of
all packets sent by another node using the same link-layer address.
Duplicate Address Detection will fail on interfaces that filter
received packets in this manner:
o  If a node performing Duplicate Address Detection discards received
packets having the same source link-layer address as the receiving
interface, it will also discard packets from other nodes also
using the same link-layer address, including Neighbor
Advertisement and Neighbor Solicitation messages required to make
Duplicate Address Detection work correctly. This particular
problem can be avoided by temporarily disabling the software
suppression of loopbacks while a node performs Duplicate Address
Detection, if it is possible to disable the suppression.
o  If a node that is already using a particular IP address discards
received packets having the same link-layer source address as the
interface, it will also discard Duplicate Address
Detection-related Neighbor Solicitation messages sent by another
node also using the same link-layer address. Consequently,
Duplicate Address Detection will fail, and the other node will
configure a non-unique address. Since it is generally impossible
to know when another node is performing Duplicate Address
Detection, this scenario can be avoided only if software
suppression of loopback is permanently disabled.
Thus, to perform Duplicate Address Detection correctly in the case
where two interfaces are using the same link-layer address, an
implementation must have a good understanding of the interface's
multicast loopback semantics, and the interface cannot discard
received packets simply because the source link-layer address is the
same as the interfaces. It should also be noted that a link-layer
specification can conflict with the condition necessary to make
Duplicate Address Detection work.
Appendix B. CHANGES SINCE RFC 1971
o  Changed document to use term "interface identifier" rather than
"interface token" for consistency with other IPv6 documents.
o  Clarified definition of deprecated address to make clear it is OK
to continue sending to or from deprecated addresses.
o  Added rules to Section 5.5.3 Router Advertisement processing to
address potential denial-of-service attack when prefixes are
advertised with very short Lifetimes.
o  Clarified wording in Section 5.5.4 to make clear that all upper
layer protocols must process (i.e., send and receive) packets sent
to deprecated addresses.
Appendix C. CHANGE HISTORY
Changes since RFC 2462 are:
o  Fixed a typo in Section 2.
o  Updated references and categorized them into normative and
informative ones.
o  Removed redundant code in denial of service protection in Section
o  Clarified that a unicasted NS or NA should be discarded while
performing Duplicate Address Detection.
o  Replaced the word "StoredLifetime" with "RemainingLifetime" with a
precise definition to avoid confusion.
o  Removed references to site-local and revise wording around the
keyword.
o  Added a note about source address selection with regards to
deprecated vs insufficient-scope addresses, etc. Added a reference
to RFC 3484 for further details.
o  Clarified what "new communication" means in Section 5.5.4.
o  Added a new subsection (5.7) to mention the possibility to use
stable storage to retain configured addresses for stability.
o  Revised the Security Considerations section with a reference to
RFC 3756 and a note that the use of IP security is not always
o  Added a note with a reference in Appendix A about the case where a
link-layer filtering conflicts with a condition to make DAD work
o  Specified that a node performing Duplicate Address Detection delay
joining the solicited-node multicast group, not just delay sending
Neighbor Solicitations, explaining the detailed reason.
o  Clarified the reason why the interface should be disabled after an
address duplicate is detected. Also clarified that the interface
may continue to be used if the interface identifier is not based
on the hardware address.
o  Clarified that the preferred lifetime for an existing configured
address is always reset to the advertised value by Router
o  Updated the description of interface identifier considering the
latest format.
Changes since draft-ietf-ipv6-rfc2462bis-00.txt are:
o  Clarified how the length of interface identifiers should be
determined, described the relationship with the prefix length
advertised in Router Advertisements, and avoided using a
particular length hard-coded in this document.
o  Added a note when an implementation uses stable storage for
autoconfigured addresses.
o  Resolved conflict with the Multicast Listener Discovery
specification about random delay for the first packet from the
host.
o  Clarified the semantics of the M and O flags based on the latest
standard and operational status. In particular, clarified that
these flags show the availability of the stateful protocol instead
of a trigger to invoke the stateful protocol. ManagedFlag and
OtherConfigFlag, which were implementation-internal variables,
were removed accordingly.
o  Recommended to perform Duplicate Address Detection for all unicast
addresses more strongly, considering a variety of different
interface identifiers, while keeping care of existing
implementations.
o  Added a requirement for a random delay befor sending Neighbor
Solicitations for Duplicate Address Detection if the address being
checked is configured by a multicasted Router Advertisements.
o  Clarified that the prefix comparison in Section 5.5.3 is based on
exact match. Also clarified the comparison described in this
document concentrates on addresses configured by the stateless
o  Revisited the author list.
o  Added IANA Considerations Section.
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Oneida Nation elects new chairman, leadership
Samantha Hernandez
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God Module is an American dark electronic band founded in 1999 from Orlando, Florida. Since 2006 they have been based out of Washington state. God Module is currently signed to Metropolis Records.

History
God Module was formed in 1999 by Jasyn Bangert and Andrew Ramirez. The band name was derived from an episode of The X-Files that dramatized a theory about a part of the human brain rumored to be responsible for mankind's belief in religion and the concept of God. The band's first album, Artificial, was released by Inception Records in 2000.

God Module has toured the US and North America frequently, touring almost yearly in the States since 2010, and have played festivals and short tours in Europe.

In 2017, Bangert and Andrew Pearson along with Patrick Hogan of Voicecoil recorded music under the name Hexheart. Hexheart released an album, Midnight On A Moonless Night, and the accompanying single for "A Thousand Times" on Metropolis Records.

Members

Current
 Jasyn Bangert - lead vocals, programming, lyrics
 Andrew Pearson - synths, backing vocals

Former
Clint Carney (Live synths,  guest vocals Séance and False Face records)
Courtney Bangert (Live synths 2003 - present randomly. Guest vocals on Artificial, Empath, Viscera, Let's Go Dark, Séance, Prophecy and The Unsound records)
Jon Siren (Live drums on the Triptych and Séance tours)
Brill (Live synths 2014 -present randomly)
Byron C Miller (Live vocals and synths 2003 - 2010. Guest Vocals on Empath, Let's Go Dark and The Magic In My Heart is Dead EP)
Andrew Ramirez (Band and live member 1999-2002. Appears on Artificial CD and Perception EP)

Discography
 Artificial (1999) – #11 CMJ RPM Charts
 Perception (EP) (2002)
 Empath (2003)
 Artificial 2.0  (2004)
 Victims Among Friends (EP) (2004)
 Viscera (2005)
 Let's Go Dark (2007)
 The Magic In My Heart Is Dead (2010)
 Rituals (EP) (2011)
 Séance (2011)
 Doppelganger (EP) (2012)
 Empath 2.0 (2013)
 Psychic Surgery: The Victims Among Friends and Perception EPs (2013)
 False Face (2014)
 Prophecy (2015)
 Unconscious (EP) (2019)
 Cross My Heart (EP) (2019)
 Unsound (Single) (2019)
 The Unsound (2019)
 The Unsound Remixes (2020)

References

External links

1999 establishments in Florida
American industrial music groups
Electronic music groups from Florida
Electronic music groups from Washington (state)
Metropolis Records artists
American musical duos

redpajama_set_name: RedPajamaWikipedia


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Cuban television and economic reality
On Sunday, December 4, 2022, the television program "Cuadrando la Caja" of Cuban Television was dedicated to economic crime. Honestly, sometimes I think that much of what is expressed in this program is a compendium of what precisely should not be done in economics. Far from providing elements to restore hope regarding the performance of the country's economy, what was felt at the end of the program was disappointment: even greater problems than the current ones can be expected in the near future.
At one point during the interventions, it was explained, for example, how verifications and inspections are carried out at private points of sale, to find out if established regulations are violated.
It is very good that the first thing is to verify the origin of the merchandise, see if they have purchase invoices and verify that they are not stolen or diverted products. Nothing to object. But then it was explained what is considered an abusive price; what is the maximum margin that a business can apply and the fines to receive if they violate the provisions.
What is an abusive price?
Already many wonder who or who had decided what is an abusive price, if the Ministry of Finance or Prices, had ruled something in this regard, or if there was any law, or decree-law, for the conformation of the prices to be set by private businesses.
Following the latest trends of delegating certain decisions to the base, be it the province or the municipalities, apparently the issue of setting prices has been one of them, which is the first mistake.
Intervening in the prices to be set by private businesses is a highly controversial field, due to all that has been demonstrated in terms of the signals it provides and the discouraging effect on economic agents.
If, furthermore, this sensitive issue is given importance at a non-central level, allowing each province or municipality to have its own opinions on what is appropriate, one can imagine the variety of interpretations, or regulations to follow, when many Municipalities or provinces may be more interested in appearing as guardians of the purchasing power of their inhabitants, than as stimulators of the business success of the companies in their localities, or of the economy in general. These are highly controversial areas.
One of the panelists asked the guest if the regulations by which the price inspectors were being guided had been widely publicized, which is probably unknown to many private businesses.
Photo: Kaloian.
The dollar, at 25, at 120 or at 170?
Later it was clarified that a dollar paid for a product imported or purchased in MLC, would have to be multiplied by 25, to calculate its cost in national currency.
Here, any inspected TCP or MSME could drop their jaws from the surprise they would receive. Where could someone buy currency for 25 pesos to continue with their business? Is there an official market to convert the national currency to MLC, for the amounts demanded by private businesses? Does the State sell foreign currency to private businesses, or does it transfer abroad its own foreign currency already in the hands of private businesses?
Even if it were allowed to calculate the cost by multiplying the currency by the official exchange rate for individuals, of USD/CUP 1:120, don't the regulators know that at that exchange rate it is impossible to buy foreign currency to keep a private business running, when the unofficial exchange rate exceeds 170 pesos per USD?
Later came the icing on the cake: the cost that is calculated – undervalued – can be multiplied by up to a maximum of 1.50, to calculate the maximum sale price. Above that, the price would already be considered abusive. This is equivalent to a 33.3% margin on sales, without considering other costs, such as salaries, transportation, rental of premises, electricity/water and other inputs, amortization of assets, interest on potential financing received, etc.
There was no mention of the 10% retail sales tax, which must be added by sellers to pay off the State, regardless of whether it has already gone into effect or would come later. Do not forget that consumers themselves would become "guardians" of the approved prices, and complaints would increase at all levels, if they are unaware of the tax treatment in billing.
There was also no mention of whether the 140% or more margin over cost, which has been the most frequent margin in the almost 30 years of existence of the state currency collecting stores, can be considered an abusive margin for the population, judging by the regulations currently applied by inspectors of private businesses. Why some rules for the private and another for the state?
Much could be argued about whether a 50% margin over cost, or 33.3% over sales, is adequate or not. But the fundamental issue is the moment in which this regulation is intended to be applied.
The dilemma: prices or lack of supply
For the reasons that are known, both of the US blockade, as well as the result of the COVID pandemic, the current war in Ukraine and its influence on the increase in the price of dissimilar products worldwide, as well as the own inefficiencies of the country, the reality is that there is still a very general shortage in state stores, both in CUP and in MLC.
It is true that private businesses have high prices, for whatever reasons, but they represent one more option to satisfy certain needs, even if they are not for all budgets and all market segments. That there are income inequalities, yes there are.
Will the municipalities or provinces have foreseen the possibility of the products disappearing in this private retail network, due to the price limits that are established? Is it more advisable not to have products than to have them at high prices? Is it preferable that the products are bought at a much higher price, through digital platforms from abroad, paid by relatives for their subsequent delivery in Cuba, than paid for in the country itself?
Everyone knows that one of the reasons for high prices may be the absence of competition, or the low supply of products. There is little supply in state stores for various reasons, but one of them is the low availability of state currency for purchases destined for stores (even in MLC).
Where are the currencies from?
Private businesses have assumed the challenge of seeking their own currencies to buy products from abroad and market them in the domestic market in national currency; They have even gotten into debt with family, friends and even with external entities.
Currencies that are difficult to replace abroad, as we all know, in order to continue the cycle. If the State cannot satisfy the demand in its own retail stores, and private businesses refrain from importing products and assuming the risks of those purchases, due to the impossibility of selling at more stimulating prices, have the municipalities/provinces foreseen the effect that would bring? Even for the demand in the state stores themselves…?
Less number of bidders would result in less competition, or less supply of products. Cuban regulators want private businesses to function in the same way as state ones have been doing; that is, that a lower supply of products does not influence prices in the market, or that prices go in another direction.
By repeating the same recipes, do you want private businesses to end up in the same situation that state-owned companies find themselves in today?
Faced with fines and price limitations, one might expect private business closures. Is that the signal that you prefer to give the market?
Fewer contract staff could be expected; Do state companies currently have the capacity to increase their efficient jobs; so that unemployment in the country does not increase?
The same municipalities would have less income from land taxes; don't they need them? The country would collect less tax on profits, which is 35% on gross profit. Is the country willing to delegate these issues to municipalities/provinces and jeopardize these revenues?
It is striking how not only stalls that could have sensitive foods for the population have been inspected. Leisure centers have also been inspected, with their prices for beer, energy drinks and other products that are not essential; where the lower income population does not normally go; where they generally go for distraction and consumers pay higher prices. Not because they are forced, but because they want to enjoy a certain environment or place. Is it also intended to regulate these prices, or is it the preamble and justification for closing certain centers that are not desired to exist?
They can tell me that the State is not there to endorse the existence of an unofficial currency market, at a higher exchange rate than the official ones. This statement may be true, but the solution is not to bury your head in the sand, and thereby pretend that this informal market does not exist. The solution is to find answers to the market's demand for foreign currency.
If no solution is found, for whatever reasons, what is not convenient is to forget reality, through measures that will not solve the problems, but will worsen them. But please, authorities, many economic policy errors have been made, which have led to this road still being paved. Think calmly. Concentrate on the sphere of production, remove the obstacles, and put aside the financial effects, go to the causes, which reside in the scarce existing supply.
Ranchers denounce delays in the issuance of permits by the ICA in Bucaramanga
Vietnam will enter the tourism sector in Cuba
MADRID, Spain.-Vietnamese companies will build a hotel in Havana and
Spoiled Source link
Abdo asks for tolerance from the European Union so that they continue contributing to education
Mario Abdo Benítez, President of the Republic, offered a greeting
JP Morgan presents its projections for the world economy in 2023
They capture a driver of the Protection Unit for cocaine shipment
Latest from Cuba
MADRID, Spain.-Vietnamese companies will build a hotel in Havana and repair two others during 2023. As
Two people die in a traffic accident in Morón
MADRID, Spain.- At least two people died in a traffic accident that occurred this Tuesday in
MIAMI, United States. — The Cuban regime extended until March 31, 2023 the deadline for importing
Those green iguanas falling from the trees
Green iguanas are not endemic to Florida. The state has a reputation as an epicenter for
The US will soon begin to deport Cuban migrants who enter the border
MIAMI, United States. — The United States will soon begin deporting inadmissible Cuban migrants who enter


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Republican legislative gerrymandering may blunt Wisconsin voters support of cannabis legalization
November 27, 2018 - In less than six weeks, on Jan. 7, 2019, Gov. Scott Walker will leave office and Gov.-elect Tony Evers will be sworn in as Wisconsin's 46th governor, Attorney General-elect Josh Kaul, other state elected officials and lawmakers will be sworn in as well as the new legislative session begins. I have been analyzing results from the Nov. 6 elections, and despite all 18 city and county cannabis...
Wisconsin Cannabis Advisory Referendums pass easily, Evers, Kaul win narrowly
November 7, 2018 - As I predicted here, here, here, here and here, all 18 Wisconsin cannabis advisory referendums passed easily in Wisconsin's Nov. 6 general election. The referendums got over a million votes Tuesday, sending a clear message to state officials that Wisconsin has had enough of cannabis prohibition. Tony Evers also defeated Gov. Scott Walker in a close election that was finally called after 1am. As of...
Wisconsin prepares to vote in state's most important cannabis-related election
November 4, 2018 - The statewide elections being held Tuesday, Nov. 6 represent Wisconsin's most important cannabis-related election ever. Not only are cannabis advisory referendums on the ballot in 16 counties and two cities, but there are numerous candidates supporting cannabis legalization up and down the ticket, starting with candidates for governor, attorney general. U.S. senate and other statewide offices all...
Gary Storck: Capital Times: Voters should pass pot referendums, defeat candidates who oppose legalization
October 27, 2018 - Here is a letter to the editor I wrote that was published Saturday, October 27, 2018 by Madison's Capital Times. Letter to the editor by Gary Storck as published by the Capital Times on Sat. Oct. 27, 2018. Gary Storck: Capital Times: Voters should pass pot referendums, defeat candidates who oppose legalization Dear Editor: When I first stumbled upon cannabis as a means to save my sight from the...
Letter To The Editor: Pot referendums aren't a liberal ploy
October 22, 2018 - On Saturday, October 20, 2018, the Wisconsin State Journal published a letter to the editor I wrote in response to comments by cannabis advisory referendum opponents in a recent State Journal article. article . The letter was also published online by the State Journal on Friday, Oct. 19, 2018. RELATED: The Cannabadger Guide to the 2018 Wisconsin County Cannabis Advisory Referendums Letter to the...
UPDATED: Cannabis comes up twice in first debate between Scott Walker and Tony Evers
October 20, 2018 - UPDATED: 10/22/2018: On Friday, October 19, Wisconsin Gov. Scott Walker and Wisconsin Superintendent of Public Instruction Tony Evers met for their first gubernatorial election debate. The subject of legalizing cannabis was raised twice, first surprisingly by Walker himself, later as a question from, one of the panel of moderators that quizzed the two candidates. The Cannabadger Guide to the 2018...
The Cannabadger Guide to the 2018 Wisconsin County Cannabis Advisory Referendums
September 26, 2018 - UPDATED: 11/02/2018: The year 2018 has been a historic year for cannabis law reform in Wisconsin. On Nov. 6, sixteen Wisconsin counties and two cities, from the Michigan border to the Illinois border, from Lake Michigan to the Mississippi River will vote on Wisconsin's archaic and punitive cannabis laws. While Dane County has twice held county cannabis advisory referendums and Madison and other...
Wisconsin Justice Institute launches Vote Cannabis 2018 website
September 18, 2018 - The Wisconsin Justice Institute (WJI)https://www.wjiinc.org/, a key player in coordinating the campaign to place advisory referendums on cannabis legalization on Wisconsin city and county ballots in the Nov. 6 general election, recently premiered a new website Vote Cannabis 2018 (https://votecannabis2018.com/) The Wisconsin Justice Institute created Vote Cannabis 2018 to serve as a hub for...
Fond du Lac County Public safety committee gives new life to cannabis advisory referendum
September 5, 2018 - On Aug. 21, the Fond du Lac County board was one of 7 counties voting on cannabis advisory referendums, but unlike the six others, rejected approving a referendum, instead voting to refer it to the Public Safety committee on a 15-8 vote on a motion by District 23 Sup. Martin Ryan. The move came during a contentious meeting that saw sheriff's deputies removing at least one person from the chambers...
UPDATED: Racine and Lincoln make 16 counties approving Nov. 6 cannabis advisory referendum
August 28, 2018 - UPDATED: 2018-08-29 2:30:52 PM BREAKING: Make that 16 counties. Cannabadger has just learned Lincoln County passed a medical cannabis advisory referendum Aug. 21 as well as Racine County passing one Aug. 28. Here are the minutes from the Lincoln County 8/21 board meeting at which it was approved by a voice vote with 22 members present. (Map below updated) Just hours before the deadline to get on...


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Undefended: Let's Get Political.
by Joshua Gibbs · November 14, 2015
This week, the best of cinematic politics…
Thomas Banks:
The scene in Godfather II where Michael Corleone refuses to let Senator Whatshisname walk on him. "Senator, my answer is this…Nothing."
The scene in Casablanca where Humphrey Bogart meets Major Strasser. "What is your nationality, Monsieur Blaine?" "I'm a drunk." "That makes him a citizen of the world."
The entirety of "Wag the Dog".
The entirety of "Good Night and Good Luck".
The doctor in "Pan's Labyrinth" stands up to the Francoist captain moments before being shot. "Following orders is all that men like you ever do."
James Banks:
The botched assassination attempt in "The Gods Must Be Crazy": "You were supposed to assassinate the President! Not the Minister of Education!"
The Honecker joke scene in "The Lives of Others". A moment that distills the sort of people who prosper when politics are totalitarian.
Rip Torn hits Norman Mailer with a hammer in "Maidstone". Notable mainly because Torn was not aware that he wasn't supposed to REALLY hit Mailer with a hammer—leading to a wrestling match in which they not only broke character but probably two or three fingers. This is political because the film involves a Cain-and-Abel style assassination attempt on a candidate for the presidency (Mailer). The fact that this is the only sequence of the film worth watching is a testament to Mailer's limits as a … anything.
The District Attorney informs Abel Morales that his new refinery will give him "political influence" in "A Most Violent Year". Not a significant event in itself, but it punctuates the film's central conflict of integrity versus corruption in a society in which integrity has to be its own reward, because there is nothing else pulling stumps for it.
President Lincoln gives a lawyerly answer about the absence of Confederate envoys in Washington in "Lincoln". What saved "Lincoln" from the sentimentality that often plagues Steven Spielberg's Important Works was its level of relative cynicism about how the political process works. What we need now is a film which will make a case for a moderate level of corruption in politics.
Remy Wilkins:
In the Loop : When Malcolm Tucker dresses down Linton Barwick in a chapel and Linton cuts him off and says:"OK. Firstly, don't raise your voice. This is a sacred place. Now, you may not believe that and I may not believe that, but, by God, it is a useful hypocrisy." In the Loop is a crude political farce whose buffoonery is increasingly believable.
Children of Men : When Theo visits his cousin Nigel in the Ministry of Arts (aka the "Ark of the Arts"). A visually dense scene that layers irony upon irony for those who ponder the artwork that appears in the background.
Henry V : Tennis Balls. "So get you hence in peace; and tell the Dauphin/ His jest will savour but of shallow wit,/ When thousands weep more than did laugh at it."
Being There : Chance's advice to the president. The solemn aphorisms of a simple gardener, mistaken for a peer, are bestowed with such weight by the movers and shakers of the United States that everyone falls under his sway. Sharp humor that holds up 30+ years later.
Burn After Reading : When a CIA Officer (played by Linton Barwick's David Rasche) is updating his CIA Superior (the comedic master J.K. Simmons) on the seemingly significant events of the main characters the Much Ado About Nothing theme is hammered home with the Superior concluding "Report back to me when, I don't know, when it makes sense."
Jon Paul Pope:
Peter Sellers, as the President of United States, calls the Soviet Premier to tell him "the bomb" has been launched in Dr. Strangelove. For my money, Sellers does the best American accent in the history of cinema. This scene is a hilarious mishmash of national foreign policy and childhood playground diplomacy. "I'm sorry, too, Dmitri… I'm very sorry… *All right*, you're sorrier than I am, but I am as sorry as well… I am as sorry as you are, Dmitri! Don't say that you're more sorry than I am, because I'm capable of being just as sorry as you are… So we're both sorry, all right?… All right." https://www.youtube.com/watch?v=6T2uBeiNXAo ;
The irascible and awesome Richard Burton trumps the city of man with an appeal to the city of God in Becket. A political maneuver like this may ring pathetic, especially when executed by the likes of Kim Davis in a country such as the USA. But then, "we are all God's fools." https://www.youtube.com/watch?v=7p9CiBJfbik
Miss Saunders, wryly played by Jean Arthur, explains how a bill becomes a law in Mr. Smith Goes to Washington. This is the more cynical version of the School House Rock song, and Arthur plays it so well. Though my favorite part of the scene is when Jimmy Stewart asks if for dinner they can just "sorta have stuff brought in on trays, you know, like big executives." https://www.youtube.com/watch?v=BZFRP67sX8o
Sir Thomas Moore (Paul Scofield) makes the case for the rule of law in A Man For All Seasons. Contemporary cinema often fetishizes vigilantism. It's nice to watch as reasonable and measured a performance as Scofield's of a screenplay with equally sane political philosophy. https://www.youtube.com/watch?v=PDBiLT3LASk
Pedro's campaign speech from Napoleon Dynamite. The entirety of the speech, "If you vote for me, all of your wildest dreams will come true," is the kernel of all political promises — from "bread and circuses," to "a chicken in every pot," to "CHANGE." https://www.youtube.com/watch?v=_TA42woVsqc
Brian Murnion:
Ikiru and the bureaucratic struggle of trying to do something cinematic with your life, like building a city park in a slum neighborhood while dying of stomach cancer. https://youtu.be/nr2d6PsRpsc
The Great Dictator's final scene as Hynkel (Charlie Chaplin) takes to the mic and addresses the world on the power empathy can have on mankind. https://youtu.be/9-cM5FLTGhU
12 Angry Men does a great job at decompartmentalizing the judicial system and discusses what parts of it are subjective or not. Even though the film takes place in mostly one location, it reaches cinematic glory with its sharp and consistent dialogue (a major influence on Aaron Sorkin). https://youtu.be/EqDd06GW76o
Z (1969), an Algerian film nominated for Best Picture that emphasizes the effects of what a dictatorship has on a European country.
The Hunt for Red October, when Jack Ryan slams his hands down on the table, interrupting the group discussion at hand, "Ramius might be trying to defect." https://youtu.be/PUvS_htXD34
Fraser Martens:
Stealing Campaign Signs, Boyhood: By filming over many years, Linklater gets to document moments in the country's history with a fictionalized reality. Lil' Mason and his dad encountering a redneck with some strong feelings on "Barack Hoo-sayn Obama" and proceeding to make off with his lawn signs is one of those (as is their encounter with an Obama supporter in the same scene.)
All of The Fog of War, but especially discussing the carpet bombing of Japan and Germany: Robert McNamara looks backwards and admits that he regrets the things he and his country did out of expediency.
"You've got to close the beach!" Jaws: Government requires balancing the economic interests of your area with other, less tangible, needs. When the mayor of Amity decides that maintaining business support by keeping the beach open instead of making the politically dangerous decision to close the beach… you might say it comes back to bite him.
"The strongest castle in these lands," Monty Python and the Holy Grail: Frustrated by his effete son's lack of interest in the huge tracts of land possessed by his potential ally's daughter, a low-level medieval schemer takes an immediate liking to the political capital inherent in considering Lancelot his son ("in a very real and legally binding sense.")
Slightly Cheating TV Pick: Ben Wyatt Bakes A Calzone For The Pie-Mary: Parks and Recreation episode "Pie-Mary": In a House of Cards culture, Parks and Recreation was refreshing in its belief that sometimes, politics could actually get good things done. But its gloves really came off in its final season, when her husband's bid for a seat in congress brought Leslie head-to-head with the silly little misogynies of political theater. The way the two of them team up to affirm each other is one of the show's best moments.
Joshua Gibbs:
Sneakers: In the final scene of the film, every member of Redford's crew gets a single demand from the NSA. Whistler asks for peace on earth and goodwill toward men, to which NSA heavy James Earl Jones said, "We are the US government. We don't do that kind of thing."
Bulworth: Just about any scene out of the middle will do, but these rhymes are especially choice: "Yeah, yeah / You can call it single-payer or Canadian way / Only socialized medicine will ever save the day! Come on now, lemme hear that dirty word – SOCIALISM!"
The Hunt for Red October: "I'm a politician, which means I'm a liar and a cheat, and when I'm not kissing babies, I'm stealing their lollipops."
Brazil: "This is your receipt for your husband… and this is my receipt for your receipt."
WarGames: Apologies, but some of the greatest scenes having to do with politics are also the least credible. Like Joshua the Computer's sentimental, "The only winning move is not to play."
Joshua Gibbs
Joshua Gibbs teaches great books, collects records and jogs to work. He and his wife have two children, both of whom have seven names. He tweets at @joshgibbs and blogs for the CiRCE Institute.
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