Originating Signaling Identifier

Central Office News

Point Of Presence / Post Office Protocol / Programmable Option Select

Simply a Matter Of Programming / Small Matter Of Programming

Multiplexer Control Option

Equivalent Queue Extended Erlang B

Voice Grade Budget

International Organization for Standardization Central Secretariat

Individual Circuit Analysis

Line Termination

National Standards Authority of Ireland

Upload

Look-Up Table

Tracking Identification Number

Transparent Asynchronous Transmitter/Receiver Interface

Hierarchy plus Input - Process - Output (charts)

Corporate Telecommunication Network (With ETSI the acronym used is CN).

Central Pulse Distributor

But Then Again (in response to IOW) / B-ISDN Terminal Adapter

Computer Network Operating System

Originating Signaling Identifier