MGX-RPM-1FE-CP Back Card Installation and
Configuration Note
This document contains the following sections:
•
Overview, page 1
•
Installing the MGX-RPM-1FE-CP Back Card, page 6
•
Removing the MGX-RPM-1FE-CP Back Card, page 8
•
Configuring the MGX-RPM-1FE-CP Back Card, page 8
•
Command Reference, page 22
•
RJ-45 Pinout Configuration, page 41
•
Understanding the LEDs, page 41
•
Related Documentation, page 41
•
Obtaining Documentation, page 42
•
Obtaining Technical Assistance, page 43
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.
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Overview
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
Before RTP header compression:
20 bytes
IP
8 bytes 12 bytes
UDP
RTP
Header
Payload
20 to 160 bytes
After RTP header compression:
2 to 4 bytes
IP/UDP/RTP header
20 to 160 bytes
12076
Payload
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Overview
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.
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3
Overview
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 on page 41.) 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 on page 41.)
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Overview
Figure 2
MGX-RPM-1FE-CP Back Card
1FE-CP
ENABLED
L
N
K
65786
A
C
T
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.
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Installing the MGX-RPM-1FE-CP Back Card
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
Bent pins
•
Bent divider
48456
•
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.
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Installing the MGX-RPM-1FE-CP Back Card
Figure 4
Damaged Connectors on Card
48459
Damaged holes
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.
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Removing the MGX-RPM-1FE-CP Back Card
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
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Configuring 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.
RPM-3(config)#
Step 2
End with CNTL/Z.
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.
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Configuring the MGX-RPM-1FE-CP Back Card
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
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Configuring the MGX-RPM-1FE-CP Back Card
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.
RPM-3(config)#
Step 2
End with CNTL/Z.
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
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Configuring the MGX-RPM-1FE-CP Back Card
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.
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Configuring the MGX-RPM-1FE-CP Back Card
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
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Configuring the MGX-RPM-1FE-CP Back Card
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:
Step 2
•
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.
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:
Step 2
•
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.
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.
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Configuring the MGX-RPM-1FE-CP Back Card
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.
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Configuring the MGX-RPM-1FE-CP Back Card
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)
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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.
RPM-3(config)#
Step 2
End with CNTL/Z.
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
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Configuring the MGX-RPM-1FE-CP Back Card
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
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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.
RPM-3(config)#
Step 2
End with CNTL/Z.
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
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Configuring the MGX-RPM-1FE-CP Back Card
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.
RPM-3(config)#
Step 2
End with CNTL/Z.
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
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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.
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Command Reference
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
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clear 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
Command Modes
EXEC
Command History
Release
(Optional) Interface type and number.
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.
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clear ppp mux
clear ppp mux
To clear PPP mux statistics, use the clear ppp mux EXEC command.
clear ppp mux [interface interface]
Syntax Description
interface
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.
(Optional) The identifier of the multilink interface for which you want to
clear counters.
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.
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ip rtp compression-connections
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
Defaults
16 connections
Command Modes
Interface configuration
Command History
Release
Number of RTP header compression connections the cache supports, in the
range from 3 to 1000. The default is 16 connections.
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.
Examples
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.
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
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ip rtp compression-connections
Related Commands
Command
Description
ip rtp header-compression
Enables RTP header compression.
show ip rtp
header-compression
Displays RTP header compression statistics.
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ip rtp header-compression
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
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ip rtp header-compression
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.
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ppp mux
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.
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ppp mux delay
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
Defaults
The default maximum delay is 800.
Command Modes
Interface configuration
Command History
Release
Usage Guidelines
The maximum number of microseconds that the processor can wait before
sending out a PPP superframe. Possible values are 0 through 4000000
microseconds.
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.
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.
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ppp mux delay
Command
Description
ppp mux subframe length
Sets the maximum length of the PPP subframe.
show ppp mux
Displays PPP mux counters for the specified multilink interface.
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ppp mux frame
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
Defaults
The default maximum length is 197.
Command Modes
Interface configuration
Command History
Release
The maximum number of bytes in any multiplexed PPP superframe. Possible
values are 0 through 512 bytes.
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.
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ppp mux pid
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
Defaults
The default is 33 (0x21), which is the IP protocol.
Command Modes
Interface configuration
Command History
Release
The default value of the PPP protocol ID. Possible values are 0 through
65534.
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.
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ppp mux subframe length
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
Defaults
The default maximum length is 195.
Command Modes
Interface configuration
Command History
Release
The maximum number of bytes in any single subframe that is to be
multiplexed. Possible values are 0 through 512 bytes.
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.
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ppp mux subframe count
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
Defaults
The default maximum is 15.
Command Modes
Interface configuration
Command History
Release
The maximum number of subframes that can be contained in a superframe.
Possible values are 0 through 15 bytes.
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.
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show ip rtp header-compression
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
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show ip rtp header-compression
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
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show ip rtp header-compression
Table 2 describes the significant fields shown in the display.
Table 2
Related Commands
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.
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.
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show ppp mux
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
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.
(Optional) The identifier of the multilink interface for which you want to
view counters.
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%
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show ppp mux
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
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RJ-45 Pinout Configuration
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
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Obtaining Documentation
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 [email protected].
To submit your comments by mail, use the response card behind the front cover of your document, or
write to the following address:
Attn Document Resource Connection
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-9883
We appreciate your comments.
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Obtaining Technical Assistance
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
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Obtaining Technical Assistance
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.
This document is to be used in conjunction with the Release Notes for the MGX-RPM-1FE-CP Back Card for Cisco IOS Release 12.2(8)MC and Cisco MGX 8850 Hardware
Installation Guide publications.
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