GDC DeskTop 554S

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The DeskTop 554S (DT 554S) is a single channel, SNMP manageable CSU/DSU that provides economical, advanced network access at full T1 or fractional T1 (FT1) rates in an attractive, compact package.  It features an onboard SNMP agent that allows assignment of an individual IP address to the unit.

Direct SNMP communications can then be established with any SNMP manager via a PPP (Point-to-Point Protocol) or SLIP (Serial Link Interface Protocol) interface.  The DT 554S is an excellent choice for branch
office environments or for central sites requiring high speed access plus standards-based network management. DT 554S units can also be used at any or all remote sites along with a central site
SpectraComm 5000 System for cost effective, integrated T1 / FT1 networks.


When your application has outgrown 56 Kbps, the DT 554S is the answer. It supplies bandwidth as high as
1.544 Mbps for remote LAN access and Internet service provisioning, while saving on equipment costs. And its V.35 or optional EIA-530 interface interconnects LAN routers, T1 multiplexers, videoconferencing, CAD/CAM and medical imaging equipment over today?s more attractively priced FT1 services. 


 The DT 554S operates at all N x 56/64 Kbps rates from 56 Kbps to 1.536 Mbps
(where N=1 to 24) and at 1.536 Mbps in framed, or 1.544 Mbps in unframed, modes. It supports D4
framing,, both the ANSI and AT&T 54016 versions of Extended Superframe (ESF), and AMI and B8ZS (clear channel) line coding, to ensure compatibility with the latest digital services. In addition, the DT 554S complies with the AT&T 54019A specification for FT1 transmission ? a requirement for access to Frame Relay services.


The DT 554S incorporates an SNMP version 1.0 compliant protocol agent, allowing direct access to local and remote CSU/DSUs for diagnostics, configuration and performance. Once an IP address is assigned (via a VT-100 type terminal connected to the management port), the DT 554S can be managed by any SNMP manager through a MIB (Management Information Base) browser or customer developed application software. MIBs are available in support of application software initiation.  Additionally, users can Telnet into the DT 554S independently of, or in conjunction with, any LAN-based controller.  SNMP communications between the DT 554S and the manager are over a standard PPP or SLIP connection to a router, terminal server or SNMP workstation.  SNMP traps can be sent to as many as four separate SNMP managers. The DT 554S supports both GDC enterprise MIBs and standard MIBs (RFC 1213 and RFC 1406).


The DT 554S simplifies both initial installation and any future reconfiguration.  Two versions of firmware can be downline loaded to the unit using TFTP (Trivial File Transmission Protocol) and the alternate version remotely selected if the first does not work in a particular application. The unit?s management port allows for soft-optioning and status monitoring via a VT-100 terminal using simple, text-based screens. An array of LEDs and front panel controlled tests quickly verify equipment operation, as well as identifying signal status and alarm conditions. To make things even easier, the DT 554S automates both Line Build-Out (LBO) and framing format selection.


The DT 554S supports powerful diagnostic tests, including a full complement of loopbacks, to isolate and quickly resolve system faults. Testing of the T1 aggregate circuit, bundled channels, and data terminal equipment (DTE) can be initiated via the SNMP manager, a Telnet session, the VT-100 interface, or convenient front panel switches. The DT 554S even has a built-in test pattern generator/error detector to minimize the need for external test equipment.  For added flexibility, selections can be made from multiple test patterns, including QRSS (Quasi-Random Signal Source) to stress test the T1 link, as well as ITU-T 511 and 2047 for data channel testing. DTE EIA status reporting and a series of
reported alarms are available for troubleshooting. In addition, ESF registers p r ovide the carrier with in-service statistics to help monitor the overall performance of the network.


Compatibility: Fully compliant with ANSI T1.403, AT&T TR6241 and AT&T TR54016

Data Rates: N x 64 Kbps or N x 56 Kbps where N = 1 to 24; up to 1.536 Mbps framed or 1.544 Mbps unframed

Data Encoding: Bipolar, return to zero (AMI or B8ZS)

Frequency: 1.544 Mbps + 50 bps

Framing: D4, AT&T 54016 ESF, ANSI T1.403 ESF, unframed

Network Interface: 1.544 Mbps channelized DS1 in consecutive or alternate DS0s or field selectable DSX-1

DTE Ports: One

DTE Interfaces: ITU-T V.35 or optional EIA-530

Timing Options: Internal clock; DTE external clock; slave timing (received loopback timing)

SNMP Compatibility: Fully compliant with SNMP version 1 RFC 1213 MIB II and RFC 1406 DS1 MIB

Enterprise MIB for DT 554S

Traps: supported: loss of signal, loss of frame, alarm indication signal, received yellow,

unavailable signal state, low average density, bipolar violations, CRC error, configuration error,

power up, TFTP fail and Firmware Load Failure

Diagnostics: Digital Loop, Line Loop, Local Test, Remote Test, Self Test (QRSS, 3:24, Prog 16Bit 2047, 511),

Local Test with Self Test and Remote test with Self Test, NI Loop

LAN Interfaces: PPP and SLIP, integral to unit

Network Manager: SUN, HP, or Netview workstation; Telnet screens, VT-100 craft interface; TFTP downloading

Power Requirements: 99 -129 VAC, 50/60 Hz, 20 W maximum

Physical and Environmental

Dimensions: 36 mm (1.4 in) H X 188 mm (7.4 in) W X 279 mm (11.0 in) D

Weight: 45 kg (1.0 lb.)

Shipping Weight: 0.9 kg (2 lb.)

Temperature: 0? to 50? C (32? to 122? F) operating; ?40? to 85? C (?40? to 185? F) non-operating

Humidity: Up to 95% without condensation

Safety Protection: UL recognized (UL 1459) and CSA certified

Ordering Information Description Part Number

DT 554S Main Unit PC card 048A102-003

(with RJ48C to RJ48C Network Cable )

Options and Accessories

530/422 Interface Card 048P042-001

V.35/530 Adapter Cable (order separately) 027H901-001

Console Port Adapter (RJ48C to DB-25) 029H210-001

Console Port Adapter Cable (order separately) 830-028-8XX

PPP/SLIP Adapter to DTE (RJ48 to DB-25F) 209-036-023

PPP/SLIP Adapter to DTE (RJ48 to DB-25M) 209-036-021

PPP/SLIP Adapter to DCE (RJ48 to DB-25M) 209-036-022

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