Carrier Access Access Navigator user manual Pop Rai

Glossary

Payload

Payload

Loopback

Permanent Call

POP

RAI

Remote

Interface

RS-232

S4 (or SLC-96)

Simple Network

Management

Protocol

SLC-96

SLC-96

Framing

The portion of a framed signal that carries services, such as voice or data, to the subscriber.

A connection that loops back only the payload portion of a signal, usually by demultiplexing and extracting the payload data and then reframing it.

A calling state resulting from a subscriber phone being left off-hook.

Point-of-Presence. A point in the network where inter-exchange carrier facilities like DS3 or OC-N meet with access facilities managed by telephone companies or other service providers.

Remote Alarm Indication. A code sent upstream in a digital signal network as a notification that a failure condition has been declared downstream. (RAI signals were previously referred to as Yellow signals.)

An interface provided by a remote Access Bank II. These include: FX analog voice lines and RS-232,SDSL, T1 Drop, andV.35 ports.

Also known as RS-232-C and EIA/TIA-232-E. A standard specifying the electrical, functional, and mechanical (connector) interface for short-distance (up to 50 feet) serial communication between computers, modems, and other peripheral equipment. The traditional DB25 connector has 25 pins, but the IBM PC popularized the smaller DB9 (or DE9) 9-pin connector.

S4 framing is named for AT&T corporation's SLC-96® Subscriber Loop Carrier system. This was a remote terminal system containing four shelves. S4 framing was used on the T1 between the central office switch and the first shelf (A), which served as the controller for the system. The S4 framing bit carried signaling information to set up calls through the terminal. The other three shelves used standard D4 framing

SNMP. A protocol that enables network operations centers (NOCs) to monitor and manage network elements across an internetwork. SNMP is a mechanism for managing TCP/IP networks. It works by exchanging information between an SNMP Manager and an SNMP Agent. In this case, the Agent resides in the Access Navigator. The Manager is a Network Management Station (NMS), which is a computer with SNMP management software. SNMP is described in standards RFC 1213 and RFC 1406.

The AT&T SLC-96® Subscriber Loop Carrier system, which was one of the first digital loop carrier systems deployed for short-haul multiplexing in the United States. The SLC- 96 terminal allows 24 analog telephone lines to be digitally multiplexed and carried over one T1 line. Up to four shelves (called A, B, C, and D) could be connected together to provide 96 telephone lines. The general specifications for the SLC-96 system was later incorporated into the Telcordia technical requirement TR-08.

SLC-96 and TR-08 terminals use two types of framing: SLC-96 DLL and SLC-96 S4 (or D4). For Shelf A, the DS1 FDL protocol is set to SLC96 to obtain SLC-96 DDL framing with its out-of-band data link management channel. For Shelf B, C, and D, the FDL is set to None to obtain standard SLC-96 S4 (or D4) framing.

Access Navigator - Release 1.8 August 2003 GlossaryGlossary-11