The eighth-year pro spent the past three seasons with New Orleans after starting his career with four years in Seattle. He was a fifth-round pick by the Seahawks in 2007.
Herring played in all 16 games the past two seasons with the Saints, but made just two starts. He has 10 starts in 97 career games, with 72 tackles and one sack.
The addition of the 30-year-old Herring comes a day after the Cowboys added veteran defensive linemen Terrell McClain and Jeremy Mincey.
AP NFL website: www.pro32.ap.org and www.twitter.com/AP-NFL