Skype is a Voice over Internet Protocol (VoIP) provider that allows users to make free phone calls from one PC to another PC. Skype allows users to call conventional phone numbers at reduced fees. Users also have access to additional features not available with traditional landlines, such as video and group calls. These features require high rates of data transfer, so a dial-up internet connection will only provide you limited access to Skype's capabilities.
Dial-up internet connection technology uses the copper cable installation of your telephone line to access the Internet. This allows wide access to the Internet at low cost to users in isolated or rural areas who do not have access to broadband. Another advantage of dial-up is the service does not drop during power outages, so if you have a backup power source for your computer you can continue using the Internet even when the power grid is down.
The trade-off of dial-up's wide coverage and low cost is it only uses the voice frequency spectrum to transmit information. This means the rate of data transfer is relatively slow when compared to DSL and cable modems. The maximum connection speed of dial-up is around 56 kilobits per second. DSL on the other hand ranges from 256 kilobits per second to over 20 megabits per second. Another disadvantage of dial-up is you cannot use your phone line while online and your Internet connection is much more likely to drop.
Skype System Requirements
Skype's download page informs users a broadband internet connection is best for voice calls. It recommends a broadband connection of at least 100 kilobits per second upload and 100 kilobits per second download. This requirement is well above the 56 kilobits per second provided by dial-up. This does not mean Skype will not work with dial-up, but it won't be reliable and the call quality will be much lower than with broadband.
Dial-Up and Skype Limitations
Although basic Skype calls may work, albeit with low quality and low reliability, the same can't be said for Skype's other telephony features. Group and video calling, for instance, requires a minimum connection of 512 kilobits per second download and 128 kilobits per second upload. For best quality, Skype recommends a broadband connection of 4 megabits per second download and 512 kilobits per second upload.