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Channelized DS3 IQ PIC (T640 Router)


Software release


  • Four DS3 ports

  • Power requirement: 0.32 A @ 48 V (15.6 W)

  • Fine-grained queuing per logical interface

  • Channelization: DS3, DS0

  • Model number: PB-4CHDS3-QPP

Hardware features

  • Data service unit (DSU) functionality

  • Subrate and scrambling:

    • Digital Link/Quick Eagle

    • Kentrox

    • Larscom

    • ADTRAN

    • Verilink

  • B3ZS line encoding

  • M13 or C-bit parity

  • Full bit error rate test (BERT)

  • Local and remote loopback testing

Software features

  • Quality of service (QoS) per channel: weighted round-robin (WRR), random early detection (RED), weighted random early detection (WRED)

  • Simple Network Management Protocol (SNMP): DS1 MIB, DS3 MIB

  • Dynamic, arbitrary channel configuration

  • Encapsulations:

    • Circuit cross-connect (CCC)

    • Translational cross-connect (TCC)

    • Frame Relay

    • High-Level Data Link Control (HDLC)

    • Point-to-Point Protocol (PPP)

Cables and connectors

  • Standard DS3 BNC coaxial cable interfaces


One tricolor per port:

  • Off—Not enabled

  • Green—Online with no alarms or failures

  • Yellow—Online with alarms for remote failures

  • Red—Active with a local alarm; router has detected a failure

Alarms, errors, and events

  • Alarm indication signal (AIS)

  • Excessive zeros (EXZ)

  • Far-end block error (FEBE)

  • Frame error

  • Idle code, Idle received

  • Line code violation (LCV)

  • Loss of signal (LOS)

  • Out of frame (OOF)

  • Parity bit (P-bit) disagreements

  • Path parity error

  • Yellow alarm bit (X-bit) disagreements

Instrumentation (counters)

  • Layer 2 per-queue and per-channel packet and byte counters