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Supported Platforms

Supported Features on ATM1 and ATM2 IQ Interfaces

Table 1 lists the supported features on ATM1 and ATM2 IQ interfaces.

Table 1: ATM1 and ATM2 IQ Supported Features

Item

ATM1

ATM2 IQ

Comments

Encapsulation and Transport Modes

ATM Adaptation Layer 5 (AAL5) circuit cross-connect (CCC)

Supported

Supported

For ATM1 and ATM2 IQ Physical Interface Cards (PICs), you can configure any combination of AAL5 CCC, nonpromiscuous cell relay, and AAL5 permanent virtual connections (PVCs) on the same PIC at the same time.

See Configuring ATM Interface Encapsulation.

Cell-relay accumulation mode: The incoming cells (1 to 8) are packaged into a single packet and forwarded to the label-switched path (LSP).

Supported

Not supported

Cell-relay accumulation mode is per PIC, not per port. If you configure accumulation mode, the entire ATM1 PIC uses the configured mode.

See Configuring ATM Interface Encapsulation.

Cell-relay promiscuous port mode: All cells from 0 through 65,535 of all VPIs (0 through 255) are sent to or received from an LSP.

Supported

Supported

For promiscuous mode, you must configure the port with atm-ccc-cell-relay encapsulation.

For ATM2 IQ multiport PICs, you can configure one or more ports in port promiscuous mode, and the other ports with any ATM encapsulation.

For ATM2 IQ PICs, you can configure one or more logical interfaces in VPI promiscuous mode, and the other logical interfaces with any ATM encapsulation.

For ATM1 PICs, if you configure one port in port mode, all ports on the PIC operate in port mode. Likewise if you configure one logical interface in VPI mode, all logical interfaces on the PIC operate in VPI mode.

See Configuring ATM Cell-Relay Promiscuous Mode.

Cell-relay promiscuous VPI mode: All cells in the VCI range 0 through 65,535 of a single VPI are sent to or received from an LSP.

Supported

Supported

Cell-relay VP shaping

Supported

Supported

For ATM2 PICs, you can configure ATM CC cell relay promiscuous mode. VP promiscuous mode allows incoming traffic on all VCIs under the VPI to be bundled and directed to an LSP. Port promiscuous mode allows all traffic coming in on the entire VPI/VCI range to be forwarded to an LSP. In both modes, traffic shaping is not permitted. The ATM2 PIC supports traffic shaping in VP promiscuous mode and cell relay VC mode.

Cell-relay VCI mode: All cells in a VCI are sent to or received from an LSP.

Supported

Supported

For ATM1 PICs, nonpromiscuous cell-relay VCI, VPI, and port modes are supported on the same PIC with ATM AAL5 PVCs or ATM AAL5 CCC.

Cell-relay VPI mode: All cells in the VCI range (0 through maximum-vcs) of a single VPI are sent to or received from an LSP.

Supported

Not supported

For ATM2 IQ PICs, nonpromiscuous cell-relay VCI mode is supported on the same PIC with ATM AAL5 PVCs or ATM AAL5 CCC.

See Configuring ATM Interface Encapsulation.

Cell-relay port mode: All cells in the VCI range (0 through maximum-vcs) of all VPIs (0 through 255) are sent to or received from an LSP.

Supported

Not supported

For ATM1 PICs, port mode is supported on the same PIC with ATM AAL5 PVCs or ATM AAL5 CCC.

See Configuring ATM Interface Encapsulation.

Ethernet over ATM encapsulation: Allows ATM interfaces to connect to devices that support only bridged-mode protocol data units (PDUs).

Supported

Supported

See Configuring ATM Interface Encapsulation.

Layer 2 circuit cell-relay, Layer 2 circuit AAL5, and Layer 2 circuit trunk transport modes: Allow you to send ATM cells or AAL5 PDUs between ATM2 IQ interfaces across a Layer 2 circuit-enabled network. Layer 2 circuits are designed to transport Layer 2 frames between provider edge (PE) routers across a Label Distribution Protocol (LDP)-signaled Multiprotocol Label Switching (MPLS) backbone.

Not supported

Supported

Transport mode is per PIC, not per port. If you configure Layer 2 circuit cell-relay, Layer 2 circuit AAL5, or Layer 2 circuit trunk transport mode, the entire ATM2 IQ PIC uses the configured transport mode.

Layer 2 circuit cell-relay mode supports both VP- and port-promiscuous modes.

See Configuring Layer 2 Circuit Transport Mode.

Layer 2 VPN cell relay and Layer 2 VPN AAL5: Allow you to carry ATM cells or AAL5 PDUs over an MPLS backbone.

Supported

Supported

See the Junos OS VPNs Library for Routing Devices.

Point-to-Point Protocol (PPP) over ATM encapsulation: Associates a PPP link with an ATM AAL5 PVC.

Not supported

Supported

For ATM2 IQ interfaces, the Junos OS supports three PPP over ATM encapsulation types:

  • atm-ppp-llc—PPP over AAL5 logical link control (LLC).
  • atm-ppp-vc-mux—PPP over AAL5 multiplex.
  • atm-mlppp-llc—Multilink PPP over AAL5 LLC. Requires a Link Services or Voice Services PIC.

    See Configuring PPP over ATM2 Encapsulation.

Other ATM Attributes

EPD (early packet discard) threshold: Limits the queue size in ATM cells of a particular VC or forwarding class configured over a VC when using VC tunnel class of service (CoS). When the first ATM cell of a new packet is received, the VC’s queue depth is checked against the EPD threshold. If the VC’s queue depth exceeds the EPD threshold, the first and all subsequent ATM cells in the packet are discarded.

Not supported

Supported

If you are using VC tunnel CoS, the EPD threshold configured at the logical unit level has no effect. You should configure each forwarding class for congestion management using either an individual EPD threshold (in other words, tail drop) or weighted random early detection (WRED) profile.

See Configuring the ATM2 IQ EPD Threshold and Configuring ATM2 IQ VC Tunnel CoS Components.

OAM F4 cell flows: Identify and report virtual path connection (VPC) defects and failures.

Not supported

Supported

See Configuring the OAM F4 Cell Flows.

OAM F5 loopback cell responses

Supported

Supported

For ATM1 interfaces, when an OAM F5 loopback request is received, the response cell is sent by the PIC. The request and response cells are not counted in the VC, logical interface, or physical interface statistics.

For ATM2 IQ interfaces, when an OAM F5 loopback request is received, the response is sent by the Routing Engine. The OAM, VC, logical interface, and physical interface statistics are incremented.

See Defining the ATM OAM F5 Loopback Cell Period and Configuring the ATM OAM F5 Loopback Cell Threshold.

Passive monitoring mode

Supported

Supported

See Enabling Passive Monitoring on ATM Interfaces.

PIC type

Supported

Supported

For ATM1 interfaces, you can include the pic-type atm1 statement.

For ATM2 IQ interfaces, you can include the pic-type atm2 statement.

See Configuring the ATM PIC Type.

Ping

Supported

Supported

For ATM1 and ATM2 IQ interfaces, when you issue the ATM ping command, you must include a logical unit number in the interface name, as shown in the following example:

ping atm interface at-1/0/0.5 vci 0.123 count 3

The logical unit number is 5 on physical interface at-1/0/0.

See the Junos OS Operational Mode Commands.

Queue length: Limits the queue size in packets of a particular VC.

Supported

Not supported

See Configuring the ATM1 Queue Length.

Real-time variable bit rate (VBR): Supports VBR data traffic with average and peak traffic parameters.

Not supported

Supported

Compared to non-real-time VBR, real-time VBR data is serviced at a higher priority. Real-time VBR is suitable for carrying packetized video and audio.

See Defining the ATM Traffic-Shaping Profile.

Shaping rates: Peak and sustained rates of traffic.

Supported

Supported

For ATM1 OC3 interfaces, the rate can be from 33 kilobits per second (Kbps) through 135.6 megabits per second (Mbps); for ATM1 OC12 interfaces, the rate can be from 33 Kbps through 276 Mbps.

For ATM2 IQ OC3 interfaces, the rate can be from 33 Kbps through 135,600,000 bits per second (bps). For ATM2 IQ OC12 interfaces, the rate can be from 33 Kbps through 271,273,396 bps (up to 50 percent of the line rate).

For ATM2 IQ OC48 interfaces, the rate can be from 33 Kbps through 2,170,107,168 bits per second (bps).

For ATM2 IQ DS3 and E3 interfaces, the rate can be from 33 Kbps to the maximum rate. The maximum rate varies depending on the ATM encapsulation and framing you configure:

  • For DS3 interfaces with direct ATM encapsulation, the maximum rate is 40,038,968 bps.
  • For DS3 interfaces with Physical Layer Convergence Protocol (PLCP) ATM encapsulation, the maximum rate is 36,864,000 bps.
  • For E3 interfaces with g.751 framing and direct ATM encapsulation, the maximum rate is 30,801,509 bps.
  • For E3 interfaces with g.751 framing PLCP ATM encapsulation, the maximum rate is 27,648,000 bps.
  • For E3 interfaces with g.832 framing, the maximum rate is 30,720,000 bps.

    See Defining the ATM Traffic-Shaping Profile.

VC tunnel CoS: Allows VCs to be opened as VC tunnels.

Not supported

Supported

On M Series routers (except the M320 and M120 routers), a VC tunnel can support four CoS queues. On the M320, M120, and T Series routers, a VC tunnel can support eight CoS queues. Within the VC tunnel, the class-based weighted fair queuing algorithm is used to schedule packet transmission from each queue. You can configure the queue admission policies, such as EPD or WRED, to control the queue size during congestion.

See Configuring ATM2 IQ VC Tunnel CoS Components.

VCI management

Supported

Supported

For ATM1 interfaces, you must specify the maximum number of VCIs by including the maximum-vcs statement in the configuration. This restricts VCIs to the range 0 through maximum-vcs. See Configuring the Maximum Number of ATM1 VCs on a VP.

For ATM2 interfaces, you must not include the maximum-vcs statement in the configuration. All ATM2 IQ interfaces support VCI numbers from 0 through 65,535. The total number of VCIs that you can open on an ATM2 IQ port depends on two factors:

  • Number of tunnels
  • Sparseness of VCI numbers (the more sparse, the fewer VCIs supported)

    For ATM1 and ATM2 IQ interfaces with promiscuous mode, the allowable maximum number of VCIs is 65,535.

VCI statistics

Supported

Supported

For ATM1 interfaces, multipoint VCI statistics are collected from indirect sources.

For ATM2 IQ interfaces, multipoint VCI statistics are collected directly from the PIC.

For ATM1 and ATM2 IQ interfaces, point-to-point VCI statistics are the same as logical interface statistics.

Published: 2013-07-30

Supported Platforms

Published: 2013-07-30