Common-network interface ring

The common-network interface ring (CNI ring) provides common-channel signaling (CCS) functionality on several Alcatel-Lucent SS7 products. It was introduced by Western Electric in the early 1980s but is still used today in all 1AESS and 4ESS,^[1] offices, and most of the wireline 5ESS offices.^[2]

It was designed and manufactured at the combined Bell Labs–WECo location in Columbus, Ohio.