Centum Call Seconds - One CCS unit represents one circuit busy for 100 seconds.
Carrier Identification Code - The four-digit number that uniquely identifies an Interconnector or Interexchange Carrier. The Carrier Identification Code is indicated by XXXX in the Carrier Access Code. In Feature Group B, the last four digits (950-XXXX) are used to identify the Interexchange Carrier. With Feature Group D, it is also used to presubscribe end users to a specific Interexchange Carrier.
Classless InterDomain Routing - CIDR allows groups of addresses to be assigned within a single network without having to identify each address. The number of bits used for the network portion determines how many addresses are available for hosts. The available addresses are identified by a CIDR prefix and that equates to the subnet mask.
Common Language Locator Identifier - A CLLI Code is an eleven-character, alphanumeric descriptor used to identify switches, points of interconnection, and other categories of telephony network elements, as well as their locations.
Class of Service
Closed User Group - A CUG is a totally private set of IP addresses and only the addresses listed in the CUG can talk to one another.
A feature that allows you to assign up to three additional telephone numbers to a single line. You can assign a unique ringing pattern to each number.