A lot of things have changed since 1999. Cell phones have touch screens, smoking isn’t allowed in public buildings, and music can be played without CDs.

One thing that hasn’t changed in the last 23 years is the Iowa football team’s defense.

“The game is definitely changing from what it used to be in 1999,” said Phil Parker, who has been the Hawkeyes’ defensive coordinator for the last 10 years. “[We use] the same philosophy of how we try to defend the run and defend the pass.”

Even with its philosophies exceeding 20 years in age, Iowa’s defense is consistently one of the best units in the Big Ten Conference and nation. Last season, the Hawkeyes led the country in interceptions with 25. Iowa ranked 17th nationally in total defense.

“I think it starts with stability,” Iowa linebackers coach Seth Wallace said of Iowa’s defensive success. “The fact that the defense has been around since 1999. The stability within that is the personnel on the coaching side of things. That stability is well-documented. I don’t think it gets enough credit behind the scenes … I think that stability, whether it be philosophically, scheme-wise, personnel-wise, when it all blends together and there’s a unique relationship that’s being formed, that’s where you’re seeing the success.”

Wallace added that the consistency of the Hawkeyes’ on-field alignment and coaching staff helps him recruit the talent Iowa needs to maintain its perennial top-25 defense. Wallace said he can show recruits that the Hawkeyes have lined up against certain offensive formations in the same fashion for years.

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During a near-four-minute answer to a question pertaining to Iowa’s defense, Wallace also expounded on why he thinks the Hawkeyes force so many turnovers.

“A lot of [the turnovers are] due to how we’re built defensively,” Wallace said at an April 6 press conference. “We’re built back-to-front … We’re getting takeaways, we’re getting interceptions, and we’re limiting the big plays. While all that’s going on, we’re still doing a pretty good job of stopping the run.”

Wallace’s opinion on the way the Hawkeyes’ defense is built isn’t universally agreed upon among Iowa’s coaches. Defensive line coach Kelvin Bell said the Hawkeyes’ defense is built front-to-back.

“That’s opinion, and everybody’s entitled to their opinion,” Bell said. “You know, he may think it’s built back-to-front. I truly believe that it starts up front. The things that we do up front allow things to happen the way they do on the back end.

“From coverage standpoints, whether we’re kind of eight-man spacing, whether we’re playing with seven-man spacing, that’s all dictated by what we can handle up front,” Bell added. “So, Seth’s entitled to his opinion, but our guys in our room, when we look at our contributions, we know, good practice, bad practice it’s predicated on how we did, not what happened on the back end.”

Parker, who oversees both Wallace and Bell, settled the debate during his time with reporters last Wednesday.

“Every year, some people talk about where we are defensively,” Parker said. “I do believe what Kelvin said. To win, you gotta win up front — offensive and defensive line. I think that’s very important. I think the comment Seth was talking about was a little bit of icing things from the back end and how we want to do it. But we need the defensive linemen. Totally, absolutely correct. But we need everybody on the team.”