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Channelized DS3 EOL PIC (M320 Router)


Software release

  • Junos OS Release 6.3 and later


  • Four DS3 ports

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

  • Supports up to 28 T1 channels per port

  • Data Service Unit (DSU) functionality

Hardware features

  • Each T1 channel supports a single High-level Data Link Control (HDLC) framer that can be configured for speeds ranging from DS0 (64 Kbps) through full T1 (1.54 Mbps)

  • Predictable throughput on all ports at 1.54 Mbps, full duplex

  • Rate limiting on input and output

  • Packet buffering, Layer 2 parsing

Software features

  • DS3 alarm and event counting

  • DS3 alarm and event detection

  • DS3 diagnostics and loopback control

  • B3ZS line encoding

  • M13 or C-bit parity

  • DS3 Simple Network Management Protocol (SNMP) support (DS3 MIB)

  • Per-packet counts and byte counts

  • Local and remote loopback testing

  • Encapsulations:

    • High-Level Data Link Control (HDLC)

    • Frame Relay

    • Circuit cross-connect (CCC)

    • Translational cross-connect (TCC)

    • Point-to-Point Protocol (PPP)

Cables and connectors

  • Custom 10-ft (3.05-m) posilock to BNC male cable, separate RX and TX


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)

  • Bit error rate (BER)

  • Equipment failure (Does not affect service)

  • Excessive zeros (EXZ)

  • Far-end block error (FEBE)

  • Frame error

  • Idle code, Idle received

  • Line code violation (LCV)

  • Local and remote loopback

  • Loss of signal (LOS)

  • Out of frame (OOF)

  • Parity bit (P-bit) disagreements

  • Path parity error

  • Yellow alarm bit (X-bit) disagreements