PoolThe one-year contract is worth $1.3 million, ESPN's Adam Schefter reports.
Pool had been a starter since Week 11 of 2006, but he had been plagued with concussion problems. He played in 11 games for the Browns last year, starting 10, before the fourth known concussion of his career sidelined him for the duration.
Despite his shortened campaign, Pool tied for the team lead with four interceptions, a career-high. He recorded 47 tackles and one sack.
The Jets needed depth at safety after trading Kerry Rhodes to the Arizona Cardinals for a couple of draft choices. The other safeties on the Jets' roster are Jim Leonhard, Eric Smith and special-teams stalwart James Ihedigbo.