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T1 PIC (M320 Router)


Software release


  • Four T1 ports

  • Power requirement: 0.08 A @ 48 V (3.7 W)

  • Supports clear channel T1 per port (1.544 Mbps per channel)

  • Supports attenuation up to –12 dBm

  • Model number: PB-4T1-RJ48

Hardware features

  • Per-port loop timing

  • Onboard DSU functionality for T1 connectivity

Software features

  • ESF and SF framing

  • B8ZS and AMI coding

  • ESF CSU counters, WRT impairments, and CRC checking

  • Local DS1 line loopback, remote line loopback

  • Configurable clock source—internal or loop

  • Encapsulations:

    • High-Level Data Link Control (HDLC)

    • Frame Relay

    • Circuit cross-connect (CCC)

    • Point-to-Point Protocol (PPP)

Cables and connectors

  • 100-ohm RJ-48 connector


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)

  • Bipolar violations

  • Excessive zeros

  • Far-end block errors (FEBE, E-bit errors)

  • Loss of frame (LOF)

  • Loss of signal (LOS)

  • Yellow alarm bit (X-bit) disagreements