Porter spent the past two seasons in Chicago but made it through just one year of a three-year, $12 million contract signed last offseason.
The 30-year-old veteran played in 30 of 32 games over the past two seasons, but dealt with knee injuries last season that contributed to his up-and-down campaign. In 2016, Porter compiled 48 tackles, nine passes defended and two interceptions.
This offseason, Bears general manager Ryan Pace added depth to the corner position -- a big weakness on a poor defense last season. Chicago added Prince Amukamara and Marcus Cooper to take over starter roles, while also signing veteran B.W. Webb. With 2014 first-round pick Kyle Fuller missing all last season with a knee injury, Pace took a 'toss numbers at the problem and see what sticks' approach to the corner position in 2017.