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MGX-RPM-1FE-CP Back Card Installation and Configuration Note

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MGX-RPM-1FE-CP Back Card Installation and Configuration Note

Table Of Contents

MGX-RPM-1FE-CP Back Card Installation and Configuration Note

Overview

PPP Multiplexing/Demultiplexing

RTP/UDP Header Compression

MGX-RPM-1FE-CP Back Card in an IP-RAN

Physical Characteristics of the MGX-RPM-1FE-CP Back Card

Installing the MGX-RPM-1FE-CP Back Card

Before You Install

Installation Steps

Removing the MGX-RPM-1FE-CP Back Card

Configuring the MGX-RPM-1FE-CP Back Card

Verifying the Version of IOS Software

Configuring the FE Interface

Configuring the FE Interface IP Address

Setting the Speed and Duplex Mode

Configuring Routing Protocol Attributes

Configuring PIM

Enabling the FE Interface

Configuring Multilink Interfaces

Configuring the Loopback Interface

Configuring Multilink PPP

Configuring IP Address Assignment

Configuring PPP Multiplexing

Configuring ACFC and PFC Handling During PPP Negotiation

Configuring RTP/UDP Compression

Configuring the RTP/UDP Compression Flow Expiration Timeout Duration

Configuring Routing Protocol Attributes

Configuring PIM

Configuring Virtual Templates

Configuring the IP Address

Configuring Multilink PPP

Enabling Link Quality Monitoring (LQM)

Configuring the Switch Interface and PVCs

Configuring the IP Address

Configuring the PVC

Saving the Configuration

Verifying the Configuration of the MGX-RPM-1FE-CP Back Card

Monitoring and Managing the MGX-RPM-1FE-CP Back Card

Command Reference

clear ip rtp header-compression

clear ppp mux

ip rtp compression-connections

ip rtp header-compression

ppp mux

ppp mux delay

ppp mux frame

ppp mux pid

ppp mux subframe length

ppp mux subframe count

show ip rtp header-compression

show ppp mux

RJ-45 Pinout Configuration

Understanding the LEDs

Related Documentation

Obtaining Documentation

World Wide Web

Ordering Documentation

Documentation Feedback

Obtaining Technical Assistance

Cisco.com

Technical Assistance Center

Contacting TAC by Using the Cisco TAC Website

Contacting TAC by Telephone


MGX-RPM-1FE-CP Back Card Installation and Configuration Note


This document contains the following sections:

Overview

Installing the MGX-RPM-1FE-CP Back Card

Removing the MGX-RPM-1FE-CP Back Card

Configuring the MGX-RPM-1FE-CP Back Card

Command Reference

RJ-45 Pinout Configuration

Understanding the LEDs

Related Documentation

Obtaining Documentation

Obtaining Technical Assistance

Overview

The MGX-RPM-1FE-CP (one-port, Fast Ethernet-Co-processor) back card is an MGX8850/RPM-PR back card that off-loads the following processes from the Route Processor Module (RPM-PR):

Compression/decompression of Real-time Transport Protocol (RTP)/User Datagram Protocol (UDP) headers (cRTP/cUDP)

Multiplexing/demultiplexing of Point-to-Point Protocol (PPP) frames

The MGX-RPM-1FE-CP back card is designed to be used with an MGX8850 that is equipped with one or more RPM-PRs and that terminates some number of T1 lines. Each MGX-RPM-1FE-CP back card has a termination capacity of up to eight T1s (four per Multilink PPP [MLP] bundle). The MGX-RPM-1FE-CP is only supported with the MLP encapsulation.

The MGX-RPM-1FE-CP back card contains one Fast Ethernet (100Base-Tx) interface. The interface has an RJ45 connector that is used to connect the card to a Category 5 un-shielded twisted pair (UTP) cable. Both half- and full-duplex operation are supported.

PPP Multiplexing/Demultiplexing

Encapsulated PPP frames contain several bytes of header information, which adds considerable overhead to a network that is used to transport PPP frames.

RFC 3153, PPP Multiplexing, describes a way to overcome this overhead. On the sending end, a multiplexor concatenates multiple PPP frames (subframes) into a single, multiplexed frame (superframe). One header is included in the superframe and the individual PPP subframes are separated by delimiters. On the receiving end, a demultiplexor uses the delimiters to separate the individual PPP subframes.

The MGX-RPM-1FE-CP back card conforms to this specification and acts as both a multiplexor and a demultiplexor.

RTP/UDP Header Compression

RTP is a protocol used for carrying packetized audio and video traffic over an IP network. RTP, described in RFC 1889, is not intended for data traffic, which uses TCP or UDP. Instead, RTP provides end-to-end network transport functions intended for applications with real-time requirements (such as audio, video, or simulation data) over multicast or unicast network services.

In an RTP frame, there is a minimum 12 bytes of the RTP header, combined with 20 bytes of IP header, and 8 bytes of UDP header. This creates a 40-byte IP/UDP/RTP header. By comparison, the RTP packet has a payload of approximately 20 to 160 bytes for audio applications that use compressed payloads. Given this ratio, it is very inefficient to transmit the IP/UDP/RTP header without compressing it.

Figure 1 RTP Header Compression

RFCs 2508 and 2509 describe a method for compressing not only the RTP header, but also the associated UDP and IP headers. Using this method, the 40 bytes of header information is compressed into approximately 2 to 4 bytes, as shown in Figure 1. Because the frames are compressed on a link-by-link basis, the delay and loss rate are lower, resulting in improved performance.

The MGX-RPM-1FE-CP back card offloads both the compression and decompression of RTP frames from the RPM-PR.


Note The MGX-RPM-1FE-CP back card can be used to perform only UDP/IP compression, in which case, the header is reduced from 28 bytes to 2 to 4 bytes.


MGX-RPM-1FE-CP Back Card in an IP-RAN

The MGX-RPM-1FE-CP back card off loads the compression/decompression of RTP/UDP headers and the multiplexing/ demultiplexing of PPP frames.

The supported use of the MGX-RPM-1FE-CP back card is within an IP-RAN of a mobile wireless network. In mobile wireless networks, radio coverage over a geographical space is provided by a network of radios and supporting electronics (Base Transceiver Station [BTS]) distributed over a wide area. Each radio and supporting electronics represents a "cell." In traditional networks, the radio signals or radio data frames collected in each cell are forwarded over a T1 (or similar low-speed, leased) line to a centralized Base Station Controller (BSC) where they are processed.

With the blurring of the lines between voice and data, several alternatives have arisen. One alternative is to replace the T1s with a cell- based AAL2/ATM approach to deliver the frames. This alternative seems to work well because the frame sizes within a wireless network match up nicely with the frame sizes used within an ATM network (10-20 bytes).

Another alternative is to encapsulate the radio frames in UDP frames and transport them over an IP network using header compression and packet multiplexing. This alternative provides better bandwidth efficiency than AAL2 and thus greater backhaul capacity. In this alternative, the MGX 8850 is used as a leased line termination and aggregation device. To enable the delivery of the aggregated back haul IP traffic to and from a routed IP network, the MGX is equipped with RPM-PR blades (which terminate and originate the frames) and MGX-RPM-1FE-CP back cards (which compress and multiplex the frames).

The nature of UDP or RTP header compression is such that compressed packets must be decompressed prior to routing. Also, to optimize network bandwidth, the frames must be multiplexed/compressed before they are sent across the T1 line (and decompressed/demultiplexed before they are sent across the FE interface).

Frames arriving at an FE interface of the MGX-RPM-1FE-CP back card are transferred to the RPM-PR. After the routing decision has been made, the frames are sent to the multiplexing/compression engine, where the PPP frames are multiplexed and the UDP and RTP headers are compressed. The resulting frames are then sent back to the RPM-PR for transmission over the appropriate T1 interface.

Conversely, frames arriving at a T1 interface of the MGX8850 are transferred to the RPM-PR and then to the decompression/demultiplexing engine. Once the UDP and RTP headers are decompressed and the PPP frames are demultiplexed, the resulting frames are sent back to the RPM-PR so that a routing decision can be made. They are then forwarded to the FE interface.

Multilink PPP (MLP) provides a standardized method for spreading traffic across multiple WAN links, while providing multivendor interoperability, packet fragmentation and proper sequencing, and load-balancing on both inbound and outbound traffic. When used in conjunction with Multilink PPP, the MGX-RPM-1FE-CP back card allows customers to increase channel capacity up to eight T1s.

This solution requires the following components:

MGX8850

RPM-PR

MGX-RPM-1FE-CP back card

Frame Relay Service Module (FRSM) card

BTS router (MWR 1941-DC)

The solution uses Open Shortest Path First (OSPF) as the routing protocol and requires MLP for transmission of the packets between the aggregation node (MGX8850) and the BTS. It requires you to configure the following:

The FE interface to support OSPF. Enable multicast routing and indicate a Protocol Independent Multicast (PIM) mode.

One or more PPP multilink interfaces with PPP mux and RTP header compression attributes.

A virtual template for each of the multilink groups.

A PVC under the switch subinterface that references the virtual template.

In addition, you must configure a connection between the PVC and the FRSM as well as a connection between the FRSM and the PVC.

Physical Characteristics of the MGX-RPM-1FE-CP Back Card

The MGX-RPM-1FE-CP back card has one Fast Ethernet (100Base-Tx) interface that can be connected to an RJ-45 cable. (For more information about the pinout configuration for the connector, see "RJ-45 Pinout Configuration" section.) It also has three LEDs that indicate the state and status of the card and the interface. (For more information about the meanings of these LEDs, see "Understanding the LEDs" section.)

Figure 2 MGX-RPM-1FE-CP Back Card

Table 1 lists the cabling specifications for 100-Mbps Fast Ethernet transmission over UTP cables.

Table 1 Specifications and Connection Limits for 100-Mbps Transmission

Parameter
RJ-45 Specification

Cable specification

Category 5 UTP, 22 to 24 AWG1

Maximum segment length

328 ft (100 m)

Maximum network length

656 ft (200 m) (with 1 repeater)2

1 Cisco Systems does not supply Category 5 UTP RJ-45 cables. These cables are available commercially.

2 This length is specifically between any two stations on a repeated segment.


Installing the MGX-RPM-1FE-CP Back Card

The MGX-RPM-1FE-CP back card must be installed as a back card to an RPM-PR front card. It can be installed in any back slot that corresponds to an RPM-PR front card except reserved slots 31 and 32, which are reserved for the Service Redundancy Modules (SRMs).


Note Only one MGX-RPM-1FE-CP back card can be installed per RPM-PR. If you have multiple RPM-PRs installed, then you can have one MGX-RPM-1FE-CP back card installed for each and therefore more than one MGX-RPM-1FE-CP back card per MGX.


Before You Install

Before you install the MGX-RPM-1FE-CP back card, be sure to:

Inspect the backplane for bent pins or bent dividers between pin rows (Figure 3). If the backplane has bent pins, do not install a card in that slot. Installing a card into a damaged backplane slot will damage the connector on the card.

Figure 3 Backplane Inspection Check Points

Inspect the card for damaged holes on the connector. If the connector has damaged holes, do not install the card. Installing a card that has a damaged connector will damage the backplane. Return damaged cards to Cisco.

Figure 4 Damaged Connectors on Card


Caution To prevent damage to the cards from static electricity, wear the supplied wrist strap and connect it to any convenient metal contact on the system or card cage before you touch any cards.


Caution Inserting the cards in the correct slot is important for all cards, but especially for the back cards because of the potential for electrical damage.

Installation Steps

To install the MGX-RPM-1FE-CP back card, do the following:


Step 1 Make sure the two extractor levers are set in. As you move the card, the levers should be flush with the vertical edge of the back card, or the card will not slide properly.

Step 2 Carefully slide the card all the way into the slot.

Step 3 Push the card into the connector until the faceplate is flush with the card cage.

Step 4 Tighten the two captive screws on the card faceplate until the faceplate is flush with the chassis.



Tip If you are having difficulty inserting the screws, look from the side to check the alignment of the holes and screws.


Removing the MGX-RPM-1FE-CP Back Card

A captive screw at the top and bottom of the faceplate of each back card secures the card to the card cage. The extraction levers let you pull the card from the backplane connector after you loosen the captive screws.

To remove the MGX-RPM-1FE-CP back card, do the following:


Step 1 Loosen the two captive screws in the faceplate using a screwdriver.

Step 2 Pull out both extractor levers simultaneously to pull the card from the backplane connector.

Step 3 Carefully pull the card out of the card cage and store it in a safe location.


Configuring the MGX-RPM-1FE-CP Back Card

To configure the MGX-RPM-1FE-CP back card, you must first access the RPM-PR command line interface (CLI). The RPM-PR CLI can be accessed using any of the following three methods:

Console port on the front of the RPM-PR

The RPM-PR has an RJ-45 connector on the front of the card module. If you configure the RPM-PR on site, connect a console terminal (an ASCII terminal or a PC running terminal emulation software) directly to the console port on your RPM-PR using an RS-232 to RJ-45 cable for CLI access. The console port is the only way to access the RPM-PR CLI when the card module is first installed into an MGX 8850 chassis.

Change card (cc) command from another MGX 8850 card

After initial configuration, you can also configure the RPM-PR through the PXM. You can access the RPM-PR CLI by using the cc (change card) command from any of the other cards in the MGX 8850 switch. The ATM switch interface on the RPM-PR must be enabled before you can use the cc command.

Telnet from a workstation, PC or another router

After initial configuration, you can also configure the RPM-PR remotely via telnet. After the RPM-PR is installed and has PVCs to other RPM-PRs or routers in the network, you can telnet to the RPM-PR CLI remotely from these other devices.

For more information about accessing the RPM-PR CLI and the basic IOS command structure, please see the RPM Installation and Configuration Guide.

Configuration of the MGX-RPM-1FE-CP back card requires the following:

Verifying the Version of IOS Software

Configuring the FE Interface

Configuring Multilink Interfaces

Configuring Virtual Templates

Configuring the Switch Interface and PVCs

Saving the Configuration

Verifying the Configuration of the MGX-RPM-1FE-CP Back Card

Verifying the Version of IOS Software

The MGX-RPM-1FE-CP back card requires Cisco IOS Release 12.2(8) MC1 or a later Cisco IOS Release 12.2 MC on the corresponding RPM-PR. To verify the version of IOS software, use the show version command.

The show version command displays the configuration of the system hardware, the software version, the names and sources of configuration files, and the boot images.

Configuring the FE Interface

To configure the FE interface of the MGX-RPM-1FE-CP back card, complete the following tasks:

Configuring the FE Interface IP Address

Setting the Speed and Duplex Mode

Configuring Routing Protocol Attributes

Configuring PIM

Enabling the FE Interface

Configuring the FE Interface IP Address

To configure the FE interface, do the following:


Step 1 At the privileged prompt, enter the following command to access configuration mode:

RPM-3# configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
RPM-3(config)#

Step 2 At the configuration prompt, enter the following command to specify the port adapter type and the location of the interface to be configured:

RPM-3(config)# interface fastethernet slot/port

The slot is the slot of the MGX8850 where the RPM-PR resides (upper=1, lower=2). The port is the number of the port on the back card.

Step 3 At the interface configuration prompt, enter the following command to assign an IP address and subnet mask to the interface:

RPM-3(config-if)# ip address x.x.x.x nnn.nnn.nnn.0 

Setting the Speed and Duplex Mode

The MGX-RPM-1FE-CP back card can run in full or half duplex mode and at 100 Mbps or 10 Mbps. It also has an auto-negotiation feature that allows the card to negotiate the speed and duplex mode with the corresponding interface on the other end of the connection.

Auto negotiation is the default setting for the speed and transmission mode. However, when using the MGX-RPM-1FE-CP back card in a wireless IP RAN solution, do not use auto negotiation. You must explicitly configure a speed of 100 Mbps and either full- or half-duplex transmission mode.

To configure speed and duplex operation, do the following while still in interface configuration mode:


Step 1 Enter the following to specify duplex operation:

RPM-3(config-if)# duplex [auto | half | full]

Step 2 Enter the following to specify speed:

RPM-3(config-if)# speed [auto | 100 | 10]

Configuring Routing Protocol Attributes

When used in the IP-RAN solution, the MGX-RPM-1FE-CP back card must be configured to support the OSPF routing protocol. To configure OSPF routing protocol attributes, do the following while still in interface configuration mode:


Step 1 Enter the following command to enable OSPF Message Digest 5 (MD5) authentication:

RPM-3(config-if)# ip ospf message-digest-key key-id md5 key 

Step 2 Enter the following command to specify the interval between hello packets that the Cisco IOS software sends on the interface:

RPM-3(config-if)# ip ospf hello-interval seconds 

Step 3 Enter the following command to set the interval at which hello packets must not be seen before neighbors declare the router down:

RPM-3(config-if)# ip ospf dead-interval seconds 

Configuring PIM

Because the MGX-RPM-1FE-CP back card is used in a multicast PPP environment, you should configure the PIM mode of the FE interface.

To configure the PIM mode, do the following while still in interface configuration mode:


Step 1 Enter the following command:

RPM-3(config-if)# ip pim {sparse-mode | sparse-dense-mode | dense-mode [proxy-register 
{list access-list | route-map map-name}]} 

Enabling the FE Interface

Once you have configured the FE interface, enable it by doing the following:


Step 1 At the interface configuration prompt, enter the following command to enable the interface:

RPM-3(config-if)# no shutdown

Configuring Multilink Interfaces

To configure the multilink interfaces to be used in conjunction with the MGX-RPM-1FE-CP back card, complete the following tasks:

Configuring the Loopback Interface

Configuring Multilink PPP

Configuring IP Address Assignment

Configuring PPP Multiplexing

Configuring RTP/UDP Compression

Configuring Routing Protocol Attributes

Configuring PIM

Configuring the Loopback Interface

The loopback interface is a software-only, virtual interface that emulates an interface that is always up. The interface-number is the number of the loopback interface that you want to create or configure. There is no limit on the number of loopback interfaces you can create.

Because the multilink interface is a virtual interface, you should create a loopback interface for the multilink interface to enable IP processing on the interface without having to assign an explicit IP address.

To configure a loopback interface for the multilink interface, do the following:


Step 1 At the privileged prompt, enter the following command to access configuration mode:

RPM-3# configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
RPM-3(config)#

Step 2 At the configuration prompt, enter the following command to create a loopback interface for the multilink interface:

RPM-3(config)# interface loopback number
RPM-3(config-if)# ip address ip_address subnet_mask

Step 3 Exit interface configuration mode:

RPM-3(config-if)# exit

Configuring Multilink PPP

As higher-speed services are deployed, Multilink-PPP (MLP) provides a standardized method for spreading traffic across multiple WAN links, while providing multivendor interoperability, packet fragmentation and proper sequencing, and load balancing on both inbound and outbound traffic. The MGX-RPM-1FE-CP back card used in conjunction with the Multilink Point-to-Point Protocol (PPP) feature provides customers with the ability to increase channel capacity to up to eight T1s.

A Multilink interface is a special virtual interface which represents a multilink PPP bundle. The multilink interface serves to coordinate the configuration of the bundled link, and presents a single object for the aggregate links. However, the individual PPP links that are aggregated together, must also be configured. Therefore, to enable Multilink PPP on multiple serial interfaces, you need to first set up the multilink interface, and then configure each of the serial interfaces and add them to the same multilink interface.

To set up the multilink interface, do the following:


Step 1 At the configuration prompt, enter the following command to specify the multilink interface to be configured:

RPM-3(config)# interface multilink number

Step 2 At the interface configuration prompt, enter the following command to enable multilink PPP operation:

RPM-3(config-if)# ppp multilink

Step 3 If using Cisco IOS Release 12.2(15)MC2a or prior, enter the following command to disable PPP multilink fragmentation:

RPM-3(config-if)# no ppp multilink fragmentation

If using Cisco IOS Release 12.3(11)T or later, enter the following command to disable PPP multilink fragmentation:

RPM-3(config-if)# ppp multilink fragment disable

Step 4 If using Cisco IOS Release 12.2(15)MC2a or prior, enter the following command to specify an identification number for the multilink interface:

RPM-3(config-if)# multilink-group group-number

If using Cisco IOS Release 12.3(11)T or later, enter the following command to specify an identification number for the multilink interface:

RPM-3(config-if)# ppp multilink group group-number

Step 5 Enter the following command to enable IP processing on the multilink interface without assigning an explicit IP address to the interface:

RPM-3(config-if)# ip unnumbered loopback number

Where number is the number of the loopback interface that you configured in Configuring the Loopback Interface.


Configuring IP Address Assignment

A point-to-point interface must be able to provide a remote node with its IP address through the IP Control Protocol (IPCP) address negotiation process. The IP address can be obtained from a variety of sources. The address can be configured through the command line, entered with an EXEC-level command, provided by TACACS+ or the Dynamic Host Configuration Protocol (DHCP), or from a locally administered pool.

IP address pooling uses a pool of IP addresses from which an incoming interface can provide an IP address to a remote node through IPCP address negotiation process. IP address pooling also enhances configuration flexibility by allowing multiple types of pooling to be active simultaneously.

To configure IP address assignment, do the following while still in interface configuration mode:


Step 1 Enter the following command to specify an IP address, an address from a specific IP address pool, or an address from the Dynamic Host Configuration Protocol (DHCP) mechanism to be returned to a remote peer connecting to this interface:

RPM-3(config-if)# peer default ip address {ip-address | dhcp | pool [pool-name]}

Configuring PPP Multiplexing

To enable and control the multiplexing of PPP frames, do the following while still in multilink interface configuration mode:


Step 1 Enter the following command to enable PPP multiplexing:

RPM-3(config-if)# ppp mux

Step 2 Enter the following commands to control the parameters of multiplexing.

To set the maximum time delay, enter:

RPM-3(config-if)# ppp mux delay integer

To set the maximum length of the subframe, enter:

RPM-3(config-if)# ppp mux subframe length integer

To set maximum length of the superframe, enter:

RPM-3(config-if)# ppp mux frame integer

To set the maximum number of subframes in a superframe, enter:

RPM-3(config-if)# ppp mux subframe count integer

To set the default PPP protocol ID, enter:

RPM-3(config-if)# ppp mux pid integer

Configuring ACFC and PFC Handling During PPP Negotiation

With Cisco IOS Release 12.2(15)MC1 and later, ACFC and PFC handling during PPP negotiation can be configured. By default, ACFC/PFC handling is not enabled.

To configure ACFC handling during PPP negotiation, do the following while in multilink interface configuration mode:


Step 1 Enter the following command to configure how the router handles the ACFC option in configuration requests received from a remote peer.

RPM-3(config-if)# ppp acfc remote {apply | reject | ignore}

Where:

apply—ACFC options are accepted and ACFC may be performed on frames sent to the remote peer.

reject—ACFC options are explicitly ignored.

ignore—ACFC options are accepted, but ACFC is not performed on frames sent to the remote peer.

Step 2 Enter the following command to configure how the router handles ACFC in its outbound configuration requests.

RPM-3(config-if)# ppp acfc local {request | forbid}

Where:

request—The ACFC option is included in outbound configuration requests.

forbid—The ACFC option is not sent in outbound configuration requests, and requests from a remote peer to add the ACFC option are not accepted.

To configure PFC handling during PPP negotiation, do the following while in multilink interface configuration mode:


Step 1 Enter the following command to configure how the router handles the PFC option in configuration requests received from a remote peer.

RPM-3(config-if)# ppp pfc remote {apply | reject | ignore}

Where:

apply—PFC options are accepted and ACFC may be performed on frames sent to the remote peer.

reject—PFC options are explicitly ignored.

ignore—PFC options are accepted, but ACFC is not performed on frames sent to the remote peer.

Step 2 Enter the following command to configure how the router handles PFC in its outbound configuration requests.

RPM-3(config-if)# ppp acfc local {request | forbid}

Where:

request—The PFC option is included in outbound configuration requests.

forbid—The PFC option is not sent in outbound configuration requests, and requests from a remote peer to add the PFC option are not accepted.

Configuring RTP/UDP Compression

Enabling RTP/UDP compression (cRTP/cUDP) on both ends of a low-bandwidth serial link can greatly reduce the network overhead if there is a lot of RTP traffic on that slow link. This compression is beneficial especially when the RTP payload size is small (for example, compressed audio payloads of 20-50 bytes).

Before you can enable RTP header compression, you must configure a serial line that uses PPP encapsulation.

To configure RTP header compression, do the following while still in multilink interface configuration mode:


Step 1 If using Cisco IOS Release 12.2(15)MC2a or prior, enter the following command to enable RTP header compression for serial encapsulations:

RPM-3(config-if)# ip rtp header-compression

If using Cisco IOS Release 12.3(11)T or later, enable RTP header compression for serial encapsulations and suppress IP ID checking during RTP compression by specifying the ignore-id keyword option:

RPM-3(config-if)# ip rtp header-compression ignore-id

Step 2 By default, the software supports a total of 16 RTP header compression connections on an interface. To change that number, enter the following command:

RPM-3(config-if)# ip rtp compression-connections number

Note The MGX-RPM-1FE-CP back card supports up to 150 RTP header compression connections on a T1 interface and up to 1000 connections per MLP bundle regardless of whether the bundle contains one T1 interface or four.



Configuring the RTP/UDP Compression Flow Expiration Timeout Duration

To minimize traffic corruption, cUDP flows expire after a period of time during which no packets are passed. When this user defined duration of inactivity occurs on a flow at the compressor, the compressor sends a full header upon receiving a packet for that flow, or, if no new packet is received for that flow, the compressor makes the CID for the flow available for new use. When a packet is received at the decompressor after the duration of inactivity has been exceeded, the packet is dropped and a context state message is sent to the compressor requesting a flow refresh.

The default expiration timeout is 5 seconds. The recommended value is 8 seconds.


Caution Failure of performance/latency scripts could occur if the expiration timeout duration is not changed to the recommended 8 seconds.

To configure the duration of the cUDP flow expiration timeout, do the following while in multilink interface configuration mode:


Step 1 Enter the following command to specify the duration of inactivity, in seconds, that when exceeded causes the cUDP flow to expire:

RPM-3(config-if)# ppp iphc max-time seconds


Configuring Routing Protocol Attributes

When used in the IP-RAN solution, the multilink interface must be configured to support the OSPF routing protocol. To configure OSPF routing protocol attributes, do the following while still in interface configuration mode:


Step 1 Enter the following command to enable OSPF Message Digest 5 (MD5) authentication:

RPM-3(config-if)# ip ospf message-digest-key key-id md5 key 

Step 2 Enter the following command to specify the interval between hello packets that the Cisco IOS software sends on the interface:

RPM-3(config-if)# ip ospf hello-interval seconds 

Step 3 Enter the following command to set the interval at which hello packets must not be seen before neighbors declare the router down:

RPM-3(config-if)# ip ospf dead-interval seconds 

Configuring PIM

Because the MGX-RPM-1FE-CP back card is used in a multicast PPP environment, you should configure the PIM mode of the multilink interface.

To configure the PIM mode, do the following while still in interface configuration mode:


Step 1 Enter the following command:

RPM-3(config-if)# ip pim {sparse-mode | sparse-dense-mode | dense-mode [proxy-register 
{list access-list | route-map map-name}]} 

Configuring Virtual Templates

To configure the virtual templates to be used in conjunction with the MGX-RPM-1FE-CP back card, complete the following tasks:

Configuring the IP Address

Configuring Multilink PPP

Enabling Link Quality Monitoring (LQM)

Configuring the IP Address

No IP address should be associated with the virtual template. To configure no IP address, do the following:


Step 1 At the privileged prompt, enter the following command to access configuration mode:

RPM-3# configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
RPM-3(config)#

Step 2 At the configuration prompt, enter the following command to specify the virtual template interface to be configured:

RPM-3(config)# interface virtual-template number

Step 3 At the interface configuration prompt, enter the following command to indicate that no IP address is associated with the virtual template:

RPM-3(config-if)# no ip address


Configuring Multilink PPP

To associate the virtual template with a multilink group, do the following while still in interface configuration mode:


Step 1 Enter the following command to enable multilink PPP operation:

RPM-3(config-if)# ppp multilink

Step 2 Enter the following command to specify link queueing parameters.

RPM-3(config-if)# ppp multilink queue depth qos number

This command sets the maximum depth for link queues when a bundle has non-FIFO queuing. The possible values are 2 through 255.

Step 3 If using Cisco IOS Release 12.2(15)MC2a or prior, enter the following command to specify an identification number for the multilink interface:

RPM-3(config-if)# multilink-group group-number

If using Cisco IOS Release 12.3(11)T or later, enter the following command to specify an identification number for the multilink interface:

RPM-3(config-if)# ppp multilink group group-number


Enabling Link Quality Monitoring (LQM)

Link Quality Monitoring (LQM) is available on all serial interfaces running PPP. LQM will monitor the link quality, and if the quality drops below a configured percentage, the router shuts down the link. The percentages are calculated for both the incoming and outgoing directions. The outgoing quality is calculated by comparing the total number of packets and bytes sent with the total number of packets and bytes received by the destination node. The incoming quality is calculated by comparing the total number of packets and bytes received with the total number of packets and bytes sent by the destination peer.

When LQM is enabled, Link Quality Reports (LQRs) are sent, in place of keepalives, every keepalive period. All incoming keepalives are responded to properly. If LQM is not configured, keepalives are sent every keepalive period and all incoming LQRs are responded to with an LQR.


Note LQR is specified in RFC 1989, PPP Link Quality Monitoring, by William A. Simpson of Computer Systems Consulting Services.


To enable LQM on the interface, do the following while still in interface configuration mode:


Step 1 Enter the following command to set the link quality threshold:

RPM-3(config-if)# ppp quality percentage

The percentage argument specifies the link quality threshold. That percentage must be maintained, or the link is deemed to be of poor quality and taken down.


Configuring the Switch Interface and PVCs

To configure the switch interface and the permanent virtual circuits (PVCs) to be used in conjunction with the MGX-RPM-1FE-CP back card, complete the following tasks:

Configuring the IP Address

Configuring the PVC

Configuring the IP Address

No IP address should be associated with the switch interface. To configure no IP address, do the following:


Step 1 At the privileged prompt, enter the following command to access configuration mode:

RPM-3# configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
RPM-3(config)#

Step 2 At the configuration prompt, enter the following command to specify the switch interface to be configured:

RPM-3(config)# interface switch number

Step 3 At the interface configuration prompt, enter the following command to indicate that no IP address is associated with the switch interface:

RPM-3(config-if)# no ip address

Configuring the PVC

To configure a PVC on a switch subinterface, do the following while still in interface configuration mode:


Step 1 Enter the following command specify the switch subinterface:

RPM-3(config-if)# interface Switch number.subinterface point-to-point

Step 2 Enter the following command to specify the PVC to be configured:

RPM-3(config-if)# pvc vpi/vci 

Step 3 Enter the following command to specify the ATM adaptation layer (AAL) and encapsulation type for the PVC and to associate the PVC with a virtual template:

RPM-3(config-if)# encapsulation aal5 encap [virtual-template number].

Saving the Configuration

Once you have completed the configuration, save the configuration by doing the following:


Step 1 At the interface prompt, press Ctrl-Z to exit configuration mode.

Step 2 Write the new configuration to nonvolatile memory as follows:

RPM-3# copy running-config startup-config

Verifying the Configuration of the MGX-RPM-1FE-CP Back Card

To verify the configuration of the PPP multiplexing and the cRTP/cUDP compression on the MGX-RPM-1FE-CP back card, enter the following command:

RPM-3# show running-config

Monitoring and Managing the MGX-RPM-1FE-CP Back Card

You can use Cisco's network management applications, such as Cisco Works for Mobile Wireless (CW4MW), to monitor and manage aspects of the MGX-RPM-1FE-CP back card.

To enable remote network management of the MGX-RPM-1FE-CP back card, do the following:


Step 1 At the privileged prompt, enter the following command to access configuration mode:

RPM-3# configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
RPM-3(config)#

Step 2 At the configuration prompt, enter the following command to assign a host name to each of the network management workstations:

RPM-3(config)# ip host hostname ip_address

Where hostname is the name assigned to the Operations and Maintenance (O&M) workstation and ip_address is the address of the network management workstation.

Step 3 Enter the following command to log messages to a syslog server host:

RPM-3(config)# logging hostname

Where hostname is the name assigned to the CW4MW workstation with the ip host command.

Step 4 Enter the following commands to create a loopback interface for O&M:

RPM-3(config)# interface loopback number
RPM-3(config-if)# ip address ip_address subnet_mask

Step 5 Exit interface configuration mode:

RPM-3(config-if)# exit

Step 6 At the configuration prompt, enter the following command to specify the recipient of a Simple Network Management Protocol (SNMP) notification operation:

RPM-3(config)# snmp-server host hostname [traps | informs] [version {1 | 2c | 3 [auth | 
noauth | priv]}] community-string [udp-port port] [notification-type]

Where hostname is the name assigned to the CW4MW workstation with the ip host command in Step 2.

Step 7 Enter the following commands to specify the public and private SNMP community names:

RPM-3(config)# snmp-server community public RO
RPM-3(config)# snmp-server community private RW

Step 8 Enter the following command to enable the sending of SNMP traps:

RPM-3(config)# snmp-server enable traps

Step 9 Enter the following command to specify the loopback interface from which SNMP traps should originate:

RPM-3(config)# snmp-server trap-source loopback number

Where number is the number of the loopback interface you configured for the O&M in Step 4.

Step 10 At the configuration prompt, press Ctrl-Z to exit configuration mode.

Step 11 Write the new configuration to nonvolatile memory as follows:

RPM-3# copy running-config startup-config

To monitor and maintain multilink and FE interfaces and to view information about the PPP mux and header compression configuration, use the following commands:

Command
Purpose

show ppp multilink

Displays MLP and multilink bundle information.

show ppp multilink interface number

Displays multilink information for the specified interface.

show interfaces fastethernet slot/port

Displays the status of the FE interface.

show ppp mux interface interface

Displays statistics for PPP frames that have passed through a given multilink interface.

show ip rtp header-compression

Displays RTP header compression statistics.

show controllers fastethernet slot/port

Displays information about initialization block, transmit ring, receive ring and errors for the Fast Ethernet controller chip.

clear counters fastethernet slot/port

Clears interface counters.

clear ppp mux interface

Clears the PPP multiplexing interface counters.

clear ip rtp header-compression

Clears RTP header compression structures and statistics.


Command Reference

The following commands have been added or changed with this release:

clear ppp mux

ppp mux

ppp mux delay

ppp mux frame

ppp mux pid

ppp mux subframe length

ppp mux subframe count

show ppp mux

The following commands were not altered but have been included for your convenience:

clear ip rtp header-compression

ip rtp compression-connections

ip rtp header-compression

show ip rtp header-compression

clear ip rtp header-compression

To clear Real-Time Transport Protocol (RTP) header compression structures and statistics, use the clear ip rtp header-compression EXEC command.

clear ip rtp header-compression [type number]

Syntax Description

type number

(Optional) Interface type and number.


Command Modes

EXEC

Command History

Release
Modification

11.3

This command was introduced.

12.2(8)MC1

This command was incorporated in Cisco IOS Release 12.2(8)MC1.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Usage Guidelines

If this command is used without an interface type and number, it clears all RTP header compression structures and statistics.

Examples

The following example clears RTP header compression structures and statistics for multilink interface 1:

clear ip rtp header-compression multilink 1

Related Commands

Command
Description

ip rtp header-compression

Enables RTP header compression.


clear ppp mux

To clear PPP mux statistics, use the clear ppp mux EXEC command.

clear ppp mux [interface interface]

Syntax Description

interface

(Optional) The identifier of the multilink interface for which you want to clear counters.


Defaults

If no interface is specified, statistics for all multilink interfaces are cleared.

Command Modes

EXEC

Command History

Release
Modification

12.2(8)MC1

This command was introduced.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Usage Guidelines

None

Examples

The following example clears PPP mux statistics for multilink interface 1:

clear ppp mux interface multilink1

Related Commands

Command
Description

show ppp mux

Displays PPP mux counters for the specified multilink interface.


ip rtp compression-connections

To specify the total number of Real-Time Transport Protocol (RTP) header compression connections that can exist on an interface, use the ip rtp compression-connections interface configuration command. To restore the default value, use the no form of this command.

ip rtp compression-connections number

no ip rtp compression-connections

Syntax Description

number

Number of RTP header compression connections the cache supports, in the range from 3 to 1000. The default is 16 connections.


Defaults

16 connections

Command Modes

Interface configuration

Command History

Release
Modification

11.3

This command was introduced.

12.0(7)T

This command was incorporated in Cisco IOS Release 12.0(7)T.

For PPP and High-Level Data Link Control (HDLC) encapsulation, the maximum number of connections increased from 256 to 1000.

For Frame Relay encapsulation, the maximum number of connections increased to 256. The maximum value for Frame Relay is fixed, not configurable.

12.1(4)E

This command was incorporated in Cisco IOS Release 12.1(4)E and supported on Cisco 7100 series routers.

12.2(8)MC1

This command was incorporated in Cisco IOS Release 12.2(8)MC1 and the upper limit for the MGX-RPM-1FE-CP back card is set at 1000.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Examples

The following example changes the number of RTP header compression connections supported to 150 and suppresses IP ID checking during RTP compression when using Cisco IOS Release 12.3(11)T or later:

interface serial 0
 encapsulation ppp
 ip rtp header-compression ignore-id
 ip rtp compression-connections 150

Related Commands

Command
Description

ip rtp header-compression

Enables RTP header compression.

show ip rtp header-compression

Displays RTP header compression statistics.


ip rtp header-compression

To enable Real-Time Transport Protocol (RTP) header compression, use the ip rtp header-compression interface configuration command. To disable RTP header compression, use the no form of this command.

ip rtp header-compression [passive] [ignore-id]

no ip rtp header-compression [passive] [ignore-id]

Syntax Description

passive

(Optional) Compresses outgoing RTP packets only if incoming RTP packets on the same interface are compressed. This option is not applicable on PPP links.

ignore-id

(Optional) Suppresses the IP ID checking in RTP/UDP header compression.


Defaults

Disabled

Command Modes

Interface configuration

Command History

Release
Modification

11.3

This command was introduced.

12.2(8)MC1

This command was incorporated in Cisco IOS Release 12.2(8)MC1.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T and the ignore-id keyword option was added.


Usage Guidelines

If you use this command without the passive keyword, the software compresses all RTP traffic.

You can compress IP/UDP/RTP headers or IP/UDP headers to reduce the size of your packets. Compressing headers is especially useful for RTP, because RTP payload size can be as small as 20 bytes, and the uncompressed header is 40 bytes.

RTP header compression is supported on serial lines using PPP encapsulation. You must enable compression on both ends of a serial connection.

Examples

The following example enables RTP header compression on Fast Ethernet interface 1, limits the number of RTP header compression connections to 10, and suppresses IP ID checking during RTP compression when using Cisco IOS Release 12.3(11)T and later:

interface serial 0
 encapsulation ppp
 ip rtp header-compression ignore-id
 ip rtp compression-connections 10

Related Commands

Command
Description

clear ip rtp header-compression

Clears RTP header compression structures and statistics.

ip rtp compression-connections

Specifies the total number of RTP header compression connections that can exist on an interface.

show ip rtp header-compression

Displays RTP header compression statistics.


ppp mux

To enable PPP multiplexing/demultiplexing, use the ppp mux command in interface configuration mode. To disable PPP multiplexing/demultiplexing, use the no form of this command.

ppp mux

no ppp mux

Syntax Description

This command has no parameters.

Defaults

PPP multiplexing/demultiplexing is disabled by default.

Command Modes

Interface configuration

Command History

Release
Modification

12.2(8)MC1

This command was introduced.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Examples

The following example enables PPP multiplexing/demultiplexing.

ppp mux

Related Commands

Command
Description

ppp mux delay

Sets the maximum delay.

ppp mux frame

Sets the maximum length of the PPP superframe.

ppp mux pid

Sets the default PPP protocol ID.

ppp mux subframe count

Sets the maximum number of subframes in a superframe.

ppp mux subframe length

Sets the maximum length of the PPP subframe.

show ppp mux

Displays PPP mux counters for the specified multilink interface.


ppp mux delay

To set the maximum time the processor can wait before sending a superframe, use the ppp mux delay command in interface configuration mode. To set the maximum delay to the default, use the no form of this command.

ppp mux delay integer

no ppp mux delay

Syntax Description

integer

The maximum number of microseconds that the processor can wait before sending out a PPP superframe. Possible values are 0 through 4000000 microseconds.


Defaults

The default maximum delay is 800.

Command Modes

Interface configuration

Command History

Release
Modification

12.2(8)MC1

This command was introduced.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Usage Guidelines

To use this command, you must first enable PPP multiplexing/demultiplexing.

When the ppp mux delay command is configured, the maximum number of microseconds that the processor can wait resolves to the nearest 200-microsecond increment. For example, if ppp mux delay 302 is specified, the actual maximum number of microseconds that the processor can wait before sending out a PPP superframe is 400. If ppp mux delay 298 is specified, the actual maximum number of microseconds that the processor can wait before sending out a PPP superframe is 200.

Examples

The following example sets the maximum delay to 200 microseconds.

ppp mux delay 200

Related Commands

Command
Description

ppp mux

Enables PPP multiplexing/demultiplexing

ppp mux frame

Sets the maximum length of the PPP superframe.

ppp mux pid

Sets the default PPP protocol ID.

ppp mux subframe count

Sets the maximum number of subframes in a superframe.

ppp mux subframe length

Sets the maximum length of the PPP subframe.

show ppp mux

Displays PPP mux counters for the specified multilink interface.


ppp mux frame

To set the maximum length (in bytes) of the PPP superframes, use the ppp mux frame command in interface configuration mode. To set the maximum length to the default, use the no form of this command.

ppp mux frame integer

no ppp mux frame

Syntax Description

integer

The maximum number of bytes in any multiplexed PPP superframe. Possible values are 0 through 512 bytes.


Defaults

The default maximum length is 197.

Command Modes

Interface configuration

Command History

Release
Modification

12.2(8)MC1

This command was introduced.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Usage Guidelines

To use this command, you must first enable PPP multiplexing/demultiplexing.

Examples

The following example sets the maximum superframe length to 80 bytes.

ppp mux frame 80

Related Commands

Command
Description

ppp mux

Enables PPP multiplexing/demultiplexing

ppp mux delay

Sets the maximum delay.

ppp mux pid

Sets the default PPP protocol ID.

ppp mux subframe count

Sets the maximum number of subframes in a superframe.

ppp mux subframe length

Sets the maximum length of the PPP subframe.

show ppp mux

Displays PPP mux counters for the specified multilink interface.


ppp mux pid

To set the default PPP protocol ID, use the ppp mux pid command in interface configuration mode. To remove this configuration, use the no form of this command.

ppp mux pid integer

no ppp mux pid

Syntax Description

integer

The default value of the PPP protocol ID. Possible values are 0 through 65534.


Defaults

The default is 33 (0x21), which is the IP protocol.

Command Modes

Interface configuration

Command History

Release
Modification

12.2(8)MC1

This command was introduced.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Usage Guidelines

To use this command, you must first enable PPP multiplexing/demultiplexing.

Examples

The following example sets the default PPP protocol ID to 8.

ppp mux pid 8

Related Commands

Command
Description

ppp mux

Enables PPP multiplexing/demultiplexing

ppp mux delay

Sets the maximum delay.

ppp mux frame

Sets the maximum length of the PPP superframe.

ppp mux subframe count

Sets the maximum number of subframes in a superframe.

ppp mux subframe length

Sets the maximum length of the PPP subframe.

show ppp mux

Displays PPP mux counters for the specified multilink interface.


ppp mux subframe length

To set the maximum length (in bytes) of the PPP subframes, use the ppp mux subframe length command in interface configuration mode. To set the maximum length to the default, use the no form of this command.

ppp mux subframe length integer

no ppp mux subframe length

Syntax Description

integer

The maximum number of bytes in any single subframe that is to be multiplexed. Possible values are 0 through 512 bytes.


Defaults

The default maximum length is 195.

Command Modes

Interface configuration

Command History

Release
Modification

12.2(8)MC1

This command was introduced.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Usage Guidelines

To use this command, you must first enable PPP multiplexing/demultiplexing. The maximum length of the subframe should be the maximum length of the superframe minus the length of the L2 header.

Examples

The following example sets the maximum subframe length to 20 bytes.

ppp mux subframe length 20

Related Commands

Command
Description

ppp mux

Enables PPP multiplexing/demultiplexing

ppp mux delay

Sets the maximum delay.

ppp mux frame

Sets the maximum length of the PPP superframe.

ppp mux pid

Sets the default PPP protocol ID.

ppp mux subframe count

Sets the maximum number of subframes in a superframe.

show ppp mux

Displays PPP mux counters for the specified multilink interface.


ppp mux subframe count

To set the maximum number of PPP subframes that can be contained in a superframe, use the ppp mux subframe count command in interface configuration mode. To set the maximum number to the default, use the no form of this command.

ppp mux subframe count integer

no ppp mux subframe count

Syntax Description

integer

The maximum number of subframes that can be contained in a superframe. Possible values are 0 through 15 bytes.


Defaults

The default maximum is 15.

Command Modes

Interface configuration

Command History

Release
Modification

12.2(8)MC1

This command was introduced.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Usage Guidelines

To use this command, you must first enable PPP multiplexing/demultiplexing.

Examples

The following example sets the maximum subframe count to 20 bytes.

ppp mux subframe count 20

Related Commands

Command
Description

ppp mux

Enables PPP multiplexing/demultiplexing

ppp mux delay

Sets the maximum delay.

ppp mux frame

Sets the maximum length of the PPP superframe.

ppp mux pid

Sets the default PPP protocol ID.

ppp mux subframe length

Sets the maximum length of the PPP subframe.

show ppp mux

Displays PPP mux counters for the specified multilink interface.


show ip rtp header-compression

To show Real-Time Transport Protocol (RTP) header compression statistics, use the show ip rtp header-compression EXEC command.

show ip rtp header-compression [type number] [detail]

Syntax Description

type number

(Optional) Interface type and number.

detail

(Optional) Displays details of each connection.

Note This keyword option is not supported on the MGX-RPM-1FE-CP back card. If specified when the command is entered, output does not display for the detail keyword.


Command Modes

EXEC

Command History

Release
Modification

11.3

This command was introduced.

12.1(5)T

This command was incorporated in Cisco IOS Release 12.1(5)T and the command output was modified to include information related to the Distributed Compressed Real-Time Transport Protocol (dCRTP) feature.

12.2(8)MC1

This command was incorporated in Cisco IOS Release 12.2(8)MC1.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Usage Guidelines

The detail keyword is not available with the show ip rtp header-compression command on a Route Switch Processor (RSP). However, the detail keyword is available with the show ip rtp header-compression command on a Versatile Interface Processor (VIP). Enter the show ip rtp header-compression type number detail command on a VIP to retrieve detailed information regarding RTP header compression on a specific interface.

Examples

The following is sample output from the show ip rtp header-compression command:

show ip rtp header-compression
RTP/UDP/IP header compression statistics:
  Interface Virtual-Access1:
    Rcvd:   0 total, 0 compressed, 0 errors 
             0 dropped, 0 buffer copies, 0 buffer failures 
    Sent:   430 total, 429 compressed, 
             15122 bytes saved, 139318 bytes sent 
             1.10 efficiency improvement factor 
    Connect:16 rx slots, 16 tx slots, 
             0 long searches, 0 misses 0 collisions, 0 negative cache hits 
             100% hit ratio, five minute miss rate 0 misses/sec, 0 max 
  

  Interface Virtual-Template15:
    Rcvd:   0 total, 0 compressed, 0 errors 
             0 dropped, 0 buffer copies, 0 buffer failures 
    Sent:   0 total, 0 compressed, 
             0 bytes saved, 0 bytes sent 
    Connect:16 rx slots, 16 tx slots, 
             0 long searches, 0 misses 0 collisions, 0 negative cache hits 

Table 2 describes the significant fields shown in the display.

Table 2 show ip rtp header-compression Field Descriptions

Field
Description

Interface Virtual-Access1

Type and number of interface.

Rcvd: total

Number of packets received on the interface.

compressed

Number of packets with compressed header.

errors

Number of errors.

dropped

Number of dropped packets.

buffer copies

Not applicable to the MGX-RPM-1FE-CP back card.

buffer failures

Not applicable to the MGX-RPM-1FE-CP back card.

Sent: total

Total number of packets sent.

compressed

Number of packets sent with compressed header.

bytes saved

Total savings in bytes due to compression.

bytes sent

Total bytes sent after compression.

efficiency improvement factor

Compression efficiency.

Connect: rx slots

Total number of receive slots.

tx slots

Total number of transmit slots.

long searches

Not applicable to the MGX-RPM-1FE-CP back card.

misses

Number of new states that were created.

negative cache hits

Not applicable to the MGX-RPM-1FE-CP back card.

hit ratio

Number of times existing states were revised.

five-minute miss rate

Not applicable to the MGX-RPM-1FE-CP back card.

max miss rate

Not applicable to the MGX-RPM-1FE-CP back card.


Related Commands

Command
Description

ip rtp compression-connections

Specifies the total number of RTP header compression connections that can exist on an interface.

ip rtp header-compression

Enables RTP header compression.


show ppp mux

To display counters for a multilink interface on the MGX-RPM-1FE-CP back card, use the show ppp mux command in EXEC mode.

show ppp mux [interface interface]

Syntax Description

interface interface

(Optional) The identifier of the multilink interface for which you want to view counters.


Defaults

If no interface is specified, statistics for all multilink interfaces are displayed.

Command Modes

EXEC

Command History

Release
Modification

12.2(8)MC1

This command was introduced.

12.2(15)MC1

This command was incorporated in Cisco IOS Release 12.2(15)MC1.

12.3(11)T

This command was incorporated in Cisco IOS Release 12.3(11)T.


Usage Guidelines

This command is only valid when issued against multilink or PPP interfaces.

Examples

The following is an example of the output generated by this command.

show ppp mux interface multilink 1

PPP Multiplex Statistics on Interface Multilink1:

Multiplex:
 Total input packets:0
 Errored input packets:0
 Valid input bytes:0
 Total output packets:0
 Multiplexed output packets:0
 Output bytes:0
 Efficiency improvement factor:0%

Demultiplex:
 Total input packets:0
 Multiplexed input packets:0
 Errored input packets:0
 Valid input bytes:0
 Total output packets:0
 Output bytes:0
 Efficiency improvement factor:0%

Table 3 describes the significant fields shown in the display.

Table 3 show ppp mux Field Descriptions

Field
Description

Total output packets

Number of outbound packets

Multiplexed output packets

Number of outbound multiplexed superframes

Output byte count

Number of outbound bytes

Total input packets

Number of inbound packets

Errored input packets

Number of inbound packets discarded due to error

Efficiency improvement factor

Percentage of efficiency improvement achieved through multiplexing or demultiplexing


The efficiency improvement factor is calculated as follows:

Multiplex efficiency improvement factor = 100 * (Total bytes saved) / (Total bytes received)

Where total bytes saved = bytes_received_at_muxer - bytes_sent_at_muxer.

Demultiplex efficiency improvement factor = 100 * (Total bytes saved) / (Total bytes sent)

Where total bytes saved = bytes_sent_at_demuxer - bytes_received_at_demuxer.

Related Commands

Command
Description

ppp mux

Enables PPP multiplexing/demultiplexing


RJ-45 Pinout Configuration

Table 4 shows the pinout configuration of the RJ-45 connectors on the MGX-RPM-1FE-CP back card.

Table 4 RJ-45 Pinout

PIN

Description

1

transmit data +

2

transmit data -

3

receive data +

4

not used

5

not used

6

receive data -

7

not used

8

not used


Understanding the LEDs

The MGX-RPM-1FE-CP back cards contains an enabled LED, which is standard on all back cards, and two status LEDs.

After system initialization, the enabled LED goes on to indicate that the back card has been enabled for operation. The following conditions must be met before the enabled LED goes on:

The MGX-RPM-1FE-CP back card is correctly connected and receiving power.

The chassis contains a valid microcode version that has been downloaded successfully.

The bus recognizes the MGX-RPM-1FE-CP back card.

If any of these conditions is not met, or if the initialization fails for other reasons, the enabled LED does not go on.

Following are the status LEDs for the FE port and an explanation of each:

Link Integrity—When on, indicates that the port is properly connected to a powered-on device. The LED is on when the link-integrity test passes and off when the link-integrity test fails.

Activity—When on, indicates either transmit or receive activity.

Related Documentation

This following documents contain important information related to the MGX-RPM-1FE-CP back card:

Release Notes for the MGX-RPM-1FE-CP Back Card for Cisco IOS Release 12.2 MC

Cisco MGX 8850 Hardware Installation Guide

Obtaining Documentation

The following sections provide sources for obtaining documentation from Cisco Systems.

World Wide Web

You can access the most current Cisco documentation on the World Wide Web at the following sites:

http://www.cisco.com

http://www-china.cisco.com

http://www-europe.cisco.com

Ordering Documentation

Cisco documentation is available in the following ways:

Registered Cisco Direct Customers can order Cisco Product documentation from the Networking Products MarketPlace:

http://www.cisco.com/cgi-bin/order/order_root.pl

Registered Cisco.com users can order the Documentation CD-ROM through the online Subscription Store:

http://www.cisco.com/go/subscription

Nonregistered Cisco.com users can order documentation through a local account representative by calling Cisco corporate headquarters (California, USA) at 408 526-7208 or, in North America, by calling 800 553-NETS(6387).

Documentation Feedback

If you are reading Cisco product documentation on the World Wide Web, you can submit technical comments electronically. Click Feedback in the toolbar and select Documentation. After you complete the form, click Submit to send it to Cisco.

You can e-mail your comments to bug-doc@cisco.com.

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We appreciate your comments.

Obtaining Technical Assistance

Cisco provides Cisco.com as a starting point for all technical assistance. Customers and partners can obtain documentation, troubleshooting tips, and sample configurations from online tools. For Cisco.com registered users, additional troubleshooting tools are available from the TAC website.

Cisco.com

Cisco.com is the foundation of a suite of interactive, networked services that provides immediate, open access to Cisco information and resources at anytime, from anywhere in the world. This highly integrated Internet application is a powerful, easy-to-use tool for doing business with Cisco.

Cisco.com provides a broad range of features and services to help customers and partners streamline business processes and improve productivity. Through Cisco.com, you can find information about Cisco and our networking solutions, services, and programs. In addition, you can resolve technical issues with online technical support, download and test software packages, and order Cisco learning materials and merchandise. Valuable online skill assessment, training, and certification programs are also available.

Customers and partners can self-register on Cisco.com to obtain additional personalized information and services. Registered users can order products, check on the status of an order, access technical support, and view benefits specific to their relationships with Cisco.

To access Cisco.com, go to the following website:

http://www.cisco.com

Technical Assistance Center

The Cisco TAC website is available to all customers who need technical assistance with a Cisco product or technology that is under warranty or covered by a maintenance contract.

Contacting TAC by Using the Cisco TAC Website

If you have a priority level 3 (P3) or priority level 4 (P4) problem, contact TAC by going to the TAC website:

http://www.cisco.com/tac

P3 and P4 level problems are defined as follows:

P3—Your network performance is degraded. Network functionality is noticeably impaired, but most business operations continue.

P4—You need information or assistance on Cisco product capabilities, product installation, or basic product configuration.

In each of the above cases, use the Cisco TAC website to quickly find answers to your questions.

To register for Cisco.com, go to the following website:

http://www.cisco.com/register/

If you cannot resolve your technical issue by using the TAC online resources, Cisco.com registered users can open a case online by using the TAC Case Open tool at the following website:

http://www.cisco.com/tac/caseopen

Contacting TAC by Telephone

If you have a priority level 1 (P1) or priority level 2 (P2) problem, contact TAC by telephone and immediately open a case. To obtain a directory of toll-free numbers for your country, go to the following website:

http://www.cisco.com/warp/public/687/Directory/DirTAC.shtml

P1 and P2 level problems are defined as follows:

P1—Your production network is down, causing a critical impact to business operations if service is not restored quickly. No workaround is available.

P2—Your production network is severely degraded, affecting significant aspects of your business operations. No workaround is available.