Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?


Channelized OC12 EOL PIC (M320 Router)


Software release

  • Junos OS Release 6.3 and later


  • One OC12 port

  • Power requirement: 0.23 A @ 48 V (10.8 W)

  • 12 DS3 channels

  • Supports IP version 4 (IPv4) unicast and multicast as well as MPLS, Intermediate System-to-Intermediate System (IS-IS), Open Shortest Path First (OSPF), and Border Gateway Protocol (BGP)

Hardware features

  • ASIC-based, high-performance throughput on all ports

  • Integrated DSU functionality with subrate and scrambling support for each DS3 channel

  • Class-of-service support for each DS3 channel

  • Dual-router SONET automatic protection switching (APS)

  • Rate policing on input for each DS3 channel

  • Rate shaping output for each DS3 channel

  • Packet buffering, Layer 2 parsing

Software features

  • M13/C-bit parity encoding

  • Full instrumentation per DS3 channel

  • DS3 diagnostics and loopback control

  • DS3 alarm and event counting and detection

  • DS3 Far-end Alarm and Control (FEAC) channel support

  • 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


One tricolor per port:

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-L, AIS-P)

  • BERT functionality (you can configure one DS3 channel in BERT mode and configure the remaining channels to transmit and receive normal traffic)

  • Bit error rate signal degrade (BERR-SD), Bit error rate signal fail (BERR-SF)

  • Bit interleaved parity errors B1, B2, B3 (CV-S, CV-L, CV-P)

  • Equipment failure (Does not affect service)

  • Errored seconds (ES-S, ES-L, ES-P), far-end bit errors REI-L, REI-P (CV-LFE, CV-PFE), far-end block error (FEBE), far-end errored seconds (ES-LFE, ES-PFE), far-end severely errored seconds (SES-LFE, SES-PFE), far-end unavailable seconds (UAS-LFE, UAS-PFE)

  • Frame error

  • Idle code, Idle received

  • Loss of frame (LOF), Loss of pointer (LOP-P), Loss of signal (LOS)

  • Out of frame (OOF)

  • Payload Mismatch (PLM-P), payload unequipped (UNEQ-P)

  • Parity bit (P-bit) disagreements

  • Path parity error

  • Remote defect indication (RDI-L, RDI-P)

  • Severely errored framing (SEF), severely errored framing seconds (SEFS-S), severely errored seconds (SES-S, SES-L, SES-P), unavailable seconds (UAS-L, UAS-P)

  • Yellow alarm bit (X-bit) disagreements