Ellison, 29, is a 6'3, 315 pound defensive tackle who has spent time with the Panthers, Ravens, 49ers, Jaguars, and most recently the Chiefs in his NFL career. Ellison played his college ball at Missouri, after which he was a third round pick by the Panthers in 2005. His only real NFL action came in 2009, where he played in fifteen games for the Jaguars (starting six), picking up sixteen tackles and one sack.
Ellison certainly isn't a top-notch option along the defensive line, but he certainly has the size to play end and make contributions as an interior rusher should he have to see the field. Hopefully, for the Patriots, he won't have to see the field much, as the return of a player such as Mike Wright would be a huge boost to the team's defensive line.
The Patriots also worked out Le Kevin Smith, Alfonso Boone, and Ryan Sims following Deaderick's suspension. Smith and Ellison were the only two to have experience in the 3-4 (Ellison with the Chiefs this training camp), and Smith specifically had time with the Patriots since being a sixth round pick in 2006 until being traded to the Broncos in August 2009.