Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

ATM Support on Circuit Emulation PICs Overview

 

The following components support ATM over MPLS (RFC 4717) and packet encapsulations (RFC 2684):

  • 4-port COC3/CSTM1 Circuit Emulation PIC on M7i and M10i routers.

  • 12-port T1/E1 Circuit Emulation PIC on M7i and M10i routers.

  • Channelized OC3/STM1 (Multi-Rate) Circuit Emulation MIC with SFP (MIC-3D-4COC3-1COC12-CE) on MX Series routers.

  • 16-Port Channelized E1/T1 Circuit Emulation MIC (MIC-3D-16CHE1-T1-CE) on MX Series routers.

Circuit Emulation PIC ATM configuration and behavior is consistent with existing ATM2 PICs.

Note

Circuit Emulation PICs require firmware version rom-ce-9.3.pbin or rom-ce-10.0.pbin for ATM IMA functionality on M7i, M10i, M40e, M120, and M320 routers running JUNOS OS Release 10.0R1 or later.

ATM OAM Support

ATM OAM supports:

  • Generation and monitoring of F4 and F5 OAM cells types:

    • F4 AIS (end-to-end)

    • F4 RDI (end-to-end)

    • F4 loopback (end-to-end)

    • F5 loopback

    • F5 AIS

    • F5 RDI

  • Generation and monitoring of end-to-end cells of type AIS and RDI

  • Monitor and terminate loopback cells

  • OAM on each VP and VC simultaneously

VP Pseudowires (CCC Encapsulation)—In the case of ATM virtual path (VP) pseudowires—all virtual circuits (VCs) in a VP are transported over a single N-to-one mode pseudowire—all F4 and F5 OAM cells are forwarded through the pseudowire.

Port Pseudowires (CCC Encapsulation)—Like VP pseudowires, with port pseudowires, all F4 and F5 OAM cells are forwarded through the pseudowire.

VC Pseudowires (CCC Encapsulation)—In the case of VC pseudowires, F5 OAM cells are forwarded through the pseudowire, while F4 OAM cells are terminated at the Routing Engine.

Protocol and Encapsulation Support

The following protocols are supported:

  • QoS or CoS queues. All virtual circuit (VCs) are unspecified bit rate (UBR).

    Note

    This protocol is not supported on M7i and M10i routers.

  • ATM over MPLS (RFC 4717)

  • ATM via dynamic labels (LDP, RSVP-TE)

NxDS0 grooming is not supported

The following ATM2 encapsulations are not supported:

  • atm-cisco-nlpid—Cisco-compatible ATM NLPID encapsulation

  • atm-mlppp-llc—ATM MLPPP over AAL5/LLC

  • atm-nlpid—ATM NLPID encapsulation

  • atm-ppp-llc—ATM PPP over AAL5/LLC

  • atm-ppp-vc-mux—ATM PPP over raw AAL5

  • atm-snap—ATM LLC/SNAP encapsulation

  • atm-tcc-snap—ATM LLC/SNAP for translational cross-connect

  • atm-tcc-vc-mux—ATM VC for translational cross-connect

  • vlan-vci-ccc—CCC for VLAN Q-in-Q and ATM VPI/VCI interworking

  • atm-vc-mux—ATM VC multiplexing

  • ether-over-atm-llc—Ethernet over ATM (LLC/SNAP) encapsulation

  • ether-vpls-over-atm-llc—Ethernet VPLS over ATM (bridging) encapsulation

Scaling Support

Table 1 lists the maximum number of virtual circuits (VCs) that are supported on various components on the M10i router, on the M7i router, and on MX Series routers.

Table 1: Maximum Number of VCs

Component

Maximum Number of VCs

12-port Channelized T1/E1 Circuit Emulation PIC

1000 VCs

4-port Channelized COC3/STM1 Circuit Emulation PIC

2000 VCs

Channelized OC3/STM1 (Multi-Rate) Circuit Emulation MIC with SFP

2000 VCs

16-Port Channelized E1/T1 Circuit Emulation MIC

1000 VCs

Limitations to ATM Support on Circuit Emulation PICs

The following limitations apply to ATM support on Circuit Emulation PICs:

  • Packet MTU—Packet MTU is limited to 2048 bytes.

  • Trunk mode ATM pseudowires—Circuit Emulation PICs do not support trunk mode ATM pseudowires.

  • OAM-FM segment—Segment F4 flows are not supported. Only end-to-end F4 flows are supported.

  • IP and Ethernet encapsulations—IP and Ethernet encapsulations are not supported.

  • F5 OAM—OAM termination is not supported.