Introducing Agenda Articulation Ports
Digital trunks are acclimated to affix to the PSTN, to a PBX, or to the WAN and are widely
available worldwide. In some areas, CAS trunks are the alone admission available. Basic
rate interface (BRI) and primary amount interface (PRI) trunks are actual accepted back connecting
a articulation aperture to the PSTN. This area maps out the assorted agenda interfaces
and explains how to apparatus and verify agenda trunks.
Digital articulation ports are begin at the circle of a packet articulation arrangement and a digital,
circuit-switched blast network. The agenda articulation anchorage interfaces that affix the
router or admission server to T1 or E1 curve canyon articulation abstracts and signaling amid the packet
network and the circuit-switched network.
Three types of agenda articulation circuits are accurate on Cisco articulation gateways:
■ T1: Uses Time Division Multiplexing (TDM) to address agenda abstracts over 24 voice
channels application CAS.
■ E1: Uses TDM to address agenda abstracts over 30 articulation channels application either CAS or
Common Channel Signaling (CCS).
■ ISDN: A circuit-switched telephone network system using CCS. Variations of
Integrated Services Digital Network (ISDN) circuits include the following:
■ BRI: 2 B (Bearer) channels and 1 D (Delta) channel
■ T1 PRI: 23 B channels and 1 D channel
■ E1 PRI: 30 B channels and 1 D channel