Houston, 30, spent his first four NFL seasons with the Raiders between 2010-13, registering 218 tackles and 16 sacks.
Houston played for both the Chicago Bears and Houston Texans in 2017, totaling 17 tackles and five sacks in 10 games.
After his time in Oakland, however, injuries began plaguing Houston. While he didn't miss a game in his first four seasons, he's missed 27 games in the past four years, which included ACL tears in 2014 and 2016.
Oakland, meanwhile, could use more pass-rushing options to complement superstar Khalil Mack. The team posted just 31 sacks in 2017, tied for 24th in the NFL, and players like Bruce Irvin, Shilique Calhoun and Mario Edwards haven't offered consistent production in that regard.
While there is a lot of potential in that trio, adding a veteran presence like Houston to complement the existing pass-rushers would make sense for Oakland.