The '''Commoncommon-network Networkinterface Interfacering''' (CNI ring) Ring''' provides [[Commoncommon-channel Channel Signalingsignaling]] (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]],<ref>[http://www.patentstorm.us/patents/5592466/description.html US Patent 5592466 -– Network interconnect backup] {{webarchive|url=https://web.archive.org/web/20110612192540/http://www.patentstorm.us/patents/5592466/description.html |date=2011-06-12 }}</ref> offices, and most of the wireline [[5ESS]] offices.<ref>{{cite journal|doi=10.1109/5.135384|title=Common channel signaling in the AT&T US 5ESS switch|year=1992|last1=Brown|first1=R.B.|last2=Holmes|first2=C.V.|last3=Lanoux|first3=M.D.|last4=Marciani|first4=T.P.|journal=Proceedings of the IEEE|volume=80|issue=4|pages=618–627}}</ref>