As Tony Siragusa watched his former coach speak with the bravado that marked his 10 seasons as a Baltimore assistant, he thought back to their first meeting. Ryan told the Ravens they would be considered one of the best defenses in league history, that people would talk about them in 100 years.  “I thought, ‘Either this guy is nuts or really thinks we’re going to be the best defense ever,’ ” said Siragusa, now an analyst with Fox. “Soon enough, you start believing.”  Underneath the bluster, Ryan remains the quintessential football coach, a brash, tough, confident teacher who inspires players with simple instruction of a complex scheme.  Ryan operates under what he calls a K.I.L.L. philosophy — Keep It Likable and Learnable. His teams attack. They practice at full speed.  He wants an all-weather offense, starting with the ground game. He said the defense would meet, as it did in Baltimore, as a unit and not be grouped by position. Ryan promised that instead of reacting to offenses, the Jets would play with an aggressiveness they lacked during their late-season collapse.  “If you take a swipe at one of ours, we’ll take two swipes at one of yours,” Ryan said. “We’re going to turn the heat up, we’re going to let the fur fly, and let’s see what happens. This is a good football team. It’s built to play the kind of style we’re going to play.”  Ryan acknowledged that while his Baltimore defenses routinely ranked among the league’s elite, they were also manned by linebacker Ray Lewis and safety Ed Reed, two of the best defensive players ever. The question lingers whether sustained success was produced by the scheme or the players.  Ryan also noted the players he developed with the Ravens. He pointed to linebacker Terrell Suggs. Some had already labeled Suggs a bust when General Manager Ozzie Newsome asked Ryan, then the defensive line coach, to work with him.  Ryan told Suggs he would become a Pro Bowler and, sure enough, he is. Ryan wants to repeat history with the struggling linebacker Vernon Gholston, whom the Jets drafted with the sixth pick over all in 2008.  “With his defenses, you don’t have to be Sherlock Holmes,” said Mike Westhoff, whom Ryan will keep as special-teams coach. “All you have to do is turn on the television and watch those guys play. There have been some other no-name characters who have been very successful in that scheme.”  The more Ryan talked, the more he separated himself from the former coach Eric Mangini.  “He’s relaxed,” cornerback Darrelle Revis said. “He’s not tense. He’s exciting.”  Ryan said his earliest memory is of the Jets playing in Super Bowl III, when his father, Buddy, was a defensive assistant. When he accepted the job, his father told him: “Don’t screw this up. This is my team.”  To which his son responded, “Don’t worry, Dad.”  Michelle Ryan, Rex’s wife, said father and son share a sense of humor, the propensity for delivering a punch line. But for all the similarities, Ryan wants to carve his own legacy, to be different, even better, than his father.  “I learned so much from my dad,” Ryan said. “I learned about the game of football, the way he would build his team on passionate, physical, aggressive people. But there were some things my dad did where I’m like, ‘I can’t believe my dad did that.’ Punching out an assistant is probably not high on the list now.”  On their first date, Ryan took his wife to a restaurant in Weatherford, Okla. He proposed to her by telephone. They’ve been married for 22 years.  Even then, she noticed his meticulous approach to football, one he showed off Wednesday with a PowerPoint presentation. Ryan balances the detailed side of his personality by being what Michelle called “the fun parent.”  After Ryan’s five-hour interview, Woody Johnson, the team’s owner, said he knew immediately that he had his coach. Ryan felt the same way, even after answering 19 pages of questions from team officials.  It did not hurt that Parcells said Ryan could use him as a reference.  “I look at it as an opportunity, an opportunity that we can win immediately,” Ryan said. “There’s no reason we shouldn’t win immediately.”  A version of this article appears in print on , on Page B11 of the New York edition with the headline: New Administration Promises Change for Jets. Order Reprints| Today's Paper|Subscribe
Rex Ryan announced Wednesday that he had already made several decisions concerning his coaching staff and that he would welcome back quarterback Brett Favre.