255-700-025
3-55
PacketStar
™
Access Concentrator 60 User Guide
, Issue 1
Release 6.3.0
Chapter 3 System Features
Enhanced DS1 Module
•
Integrated Local Management Interface Specification Version 4.0,
af-ilmi-0065.000
Hardware Features
•
Number of ports: two
•
Connector type: four BNC connectors for the two ports (each port has
one receive connector and one transmit connector)
•
Line rate: 34.368 Mbps (typical)
Enhanced DS1 Module
The Enhanced DS1/ module provides six ports, each with a line rate of
1.544 Mbps.The interfaces support
American National Standards Institute (ANSI)
T1.403
, af-phy-0016.000 and af-test-0037.000. Each port can be
independently configured to provide services for channelized and
unchannelized frame relay configurations, circuit emulation service, dynamic
bandwidth circuit emulation service, and ATM service. This module has three
types of light-emitting diode (LED) indicators: FAIL, ACTIVE and LOS (loss of
signal).
The module has built-in channel service unit (CSU) capability that allows it
to interface directly to a DS1DS1/T1T1 line with multiple repeaters. This
feature allows the module to interface with a time-division multiplex (TDM)
channelized DS1/T1 circuit. Configured for channelized T1 service, the
Enhanced DS1 module maps up to 24 individual high-level data link control
(HDLC) data links on a single T1 connection (144 HDLC data links per
module). This module also provides a data service unit/channel service unit
(DSU/CSU) for each port in order to configure individual DS-0s.
The user can configure this module to provide N x 64 Kbps (fractional DS1)
structured circuit-emulation service. When configured for DS1 circuit-
emulation service, the Enhanced DS1 module interfaces with TDM
channelized DS1 circuits. It converts channelized digital signals (usually voice
data) to ATM virtual channels. This module can adapt a maximum of 24 DS0
channels per port to ATM virtual channels with individual Virtual Path
Identifiers (VPIs) and Virtual Channel Identifiers (VCIs) using structured
(channelized) circuit emulation. Signaling bit transport is also provided,
based on ATM Forum standards for channel-associated signaling (CAS). This
module can connect to a device using 56 Kbps with 8 Kbps for robbed-bit
signaling per DS0. With the 64 Kbps "clear channel" capability, the Enhanced
DS1 module can connect to a device using a ISDN primary rate interface
(PRI) service. Because this structured circuit-emulation service can be
configured to use only a fraction of the time slots, the user can configure
several independent emulated circuits to share one service interface.
The Enhanced DS1 module uses ATM Forum specifications UNI 3.0 or UNI
3.1, which allows any DS1 port to act as a user network interface (UNI), or
an interim inter-switch protocol (IISP) user or network interface to an ATM
network.