ATM Circuit Emulation

The DSU is configured for service via a menu system which can be displayed on a terminal or PC workstation either locally or via a LAN.


A range of interfaces for both fibre and copper media are available. Separate models support native ATM traffic streams or Circuit emulation traffic for carrying video or voice bundles. Important features of all Metrodata DSUs are built in diagnostics for identifying device or network faults and Performance monitoring statistics which are stored for a 24 hour period.

The drive towards converged network infrastructure means that there is often a requirement to transport legacy traffic over a converged ATM network. Two options exist: either to replace or upgrade the legacy equipment to support native ATM interfaces; or to use an ATM CE DSU to provide a conversion between non-ATM and ATM traffic. The Metrodata CE DSU offers a wide range of legacy interfaces including E1, E2, E3 and DS3 and supports all common interfaces for connection to the ATM network equipment.

For legacy traffic to traverse an ATM network the DSU must Segment the traffic into a stream of ATM cells, and the virtual connection must be made and managed. At the far end the DSU must Reassemble the traffic into its original bit-pattern. The segmentation and reassembly processes are as defined in ITU I 363.1 AAL.1. The Metrodata Circuit Emulation DSU solves this problem by enabling non-ATM traffic to traverse an ATM network at an economic cost. The ATM CE DSU is a 2-port device that can be configured to a wide choice of interface standards to provide the link between the Customer premises and the Carrier's WAN.

Bandwidth Adaption

The DSU consists of a common services unit carrying the Customer-side CE interface plus an ATM UNI port to permit connection to an ATM network. Built in buffer storage caters for transient traffic bursts without loss of data.

Application Diagram

Environment
Temp	0 - 50 deg
Humidity	0 - 95% RH, non condensing
Pressure	86 - 106 KPA

Power Supply
AC Mains	100 - 250VAC, 50-400Hz, 250mA, IEC connector
DC Power	-36 to -72 VDC, 200-100mA

Packaging
Type	1U, 19inch rackmount
Dimensions	425 x 213 x 44 (W x D x H)

Compliance
Safety	EN60950
EMC	EN55022, EN50082
Management	RFC1213 (MIBII), RFC1495 (Telnet), RFC1157 (SNMP), RFC1406 (DS1/E1), Metro MIB (DSU), RFC1215 (Traps)
Statistics	G.821, AT&T54016:15min, 24hr totals

Status & Diagnostics
Loopbacks	Local per port
L0/1 Stats	Transmission faults
L2 Stats	Cell throughput, good cells, bad cells, corrected cells

Alarms
Line	Major, Minor
UNI	ATM Uni Fault

	Part Number
Electrical Network Interfaces	100-250 AC Mains	-48 DC Power
E3 - E1 CE	80-11-002	80-23-002
E3 - E2 CE	80-11-009	80-23-009
DS3 - E1 CE	80-11-003	80-23-003
DS3 - E2 CE	80-11-010	80-23-010
DS3 - E3 CE	80-11-016	80-23-016
STM1 RJ45NE - E1 CE	80-11-038	80-23-038
STM1 RJ45NE - E2 CE	80-11-039	80-23-039
STM1 RJ45NE - E3 CE	80-11-040	80-23-040
STM1 RJ45NE - DS3CE	80-11-041	80-23-041

	Part Number
Fibre Network Interfaces	100-250 AC Mains	-48 DC Power
STM-1 MM SC - E1 CE	80-11-026	80-23-026
STM-1 MM SC - E2 CE	80-11-028	80-23-028
STM-1 MM SC - E3 CE	80-11-030	80-23-030
STM-1 MM SC - DS3 CE	80-11-032	80-23-032
STM-1 SM SH SC - E1 CE	80-11-027	80-23-027
STM-1 SM SH SC - E2 CE	80-11-029	80-23-029
STM-1 SM SH SC - E3 CE	80-11-031	80-23-031
STM-1 SM SH SC - DS3 CE	80-11-033	80-23-033
STM-1 SM LH SC - E1 CE	80-11-034	80-23-034
STM-1 SM LH SC - E2 CE	80-11-035	80-23-035
STM-1 SM LH SC - E3 CE	80-11-036	80-23-036
STM-1 SM LH SC - DS3 CE	80-11-037	80-23-037