Table Of Contents
Configuring a High-Speed Serial Interface
Converting HSSI to Clock Master
Configuring a Synchronous Serial Interface
Synchronous Serial Configuration Task List
Specifying a Synchronous Serial Interface
Specifying Synchronous Serial Encapsulation
Configuring Half-Duplex and Bisync for Synchronous Serial Port Adapters on Cisco 7200 Series Routers
Configuring Compression Service Adapters on Cisco 7500 Series Routers
Configuring Compression of HDLC Data
Configuring Real-Time Transport Protocol Header Compression
Configuring Data Compression AIM
Using the NRZI Line-Coding Format
Inverting the Transmit Clock Signal
Configuring DTR Signal Pulsing
Ignoring DCD and Monitoring DSR as Line Up/Down Indicator
Specifying the Serial Network Interface Module Timing
Specifying G.703 and E1-G.703/G.704 Interface Options
Configuring a Channelized T3 Interface Processor
Channelized T3 Configuration Task List
Configuring T3 Controller Support for the Cisco AS5800
Configuring External T1 Channels
Troubleshooting the T3 and T1 Channels
Monitoring and Maintaining the CT3IP
Configuring Maintenance Data Link Messages
Enabling Performance Report Monitoring
Configuring for BERT on the Cisco AS5300
Verifying BERT on the Cisco AS5300
Configuring T1 Cable Length and T1/E1 Line Termination
Configuring PA-E3 and PA-2E3 Serial Port Adapters
PA-E3 and PA-2E3 Serial Port Adapter Configuration Task List
Configuring the PA-E3 Port Adapter
Troubleshooting the PA-E3 Port Adapter
Monitoring and Maintaining the PA-E3 Port Adapter
Configuring PA-T3 and PA-2T3 Serial Port Adapters
PA-T3 and PA-2T3 Port Adapter Configuration Task List
Configuring the PA-T3 Port Adapter
Troubleshooting the PA-T3 Port Adapter
Monitoring and Maintaining the PA-T3 Port Adapter
Configuring a Packet OC-3 Interface
Packet OC-3 Interface Configuration Task List
Selecting a Packet OC-3 Interface
Configuring an Interface for Internal Loopback
Configuring an Interface for Line Loopback
Setting the Source of the Transmit Clock
Configuring an Alarm Indication Signal
Configuring a DPT OC-12c Interface
OC-12c Interface Configuration Task List
Configuring the Dynamic Packet Transport Interface
Configuring Intelligent Protection Switching
Configuring Automatic Protection Switching of Packet-over-SONET Circuits
Configuring APS Working and Protect Interfaces
Monitoring and Maintaining APS
Configuring SONET Alarm Reporting
Configuring a Protection Switch
Configuring Serial Interfaces for CSU/DSU Service Modules
Fractional T1/FT/WIC CSU/DSU Service Module Configuration Task List
Enabling Data Inversion Before Transmission
Specifying the Frame Type of an FT/T1 Line
Specifying the CSU Line Build-Out
Specifying FT1/T1 Line-Code Type
Enabling Loopcodes That Initiate Remote Loopbacks
2-Wire and 4-Wire, 56/64-kbps CSU/DSU Service Module Configuration Task List
Setting the Network Line Speed
Enabling Scrambled Data Coding
Changing Between Digital Data Service and Switched Dial-Up Modes
Enabling Acceptance of a Remote Loopback Request
Configuring Low-Speed Serial Interfaces
Understanding Half-Duplex DTE and DCE State Machines
Half-Duplex DTE State Machines
Half-Duplex DCE State Machines
Changing Between Controlled-Carrier and Constant-Carrier Modes
Placing a Low-Speed Serial Interface in Controlled-Carrier Mode
Placing a Low-Speed Serial Interface in Constant-Carrier Mode
Changing Between Synchronous and Asynchronous Modes
Serial Interface Configuration Examples
Interface Enablement Configuration Examples
Channelized T3 Interface Processor Configuration Examples
Typical CT3IP Controller Configuration Examples
CT3IP Configuration with Default Values Accepted Example
CT3IP External Ports Configuration Example
CT3IP Maintenance Data Link Example
CT3IP Performance Monitoring Example
BERT Profile Configuration Example
E2 Clock Rate Configuration Example
CT3IP BERT Test Pattern Example
CT3IP Remote FDL Loopback Example
PA-E3 Serial Port Adapter Configuration Example
PA-T3 and PA-2T3 Configuration Example
Packet OC-3 Interface Configuration Examples
Packet-Over-SONET OC-3 Configuration
Packet OC-3 Configuration with Default Values Accepted Example
Two Routers Connected Back-to-Back Example
DPT OC-12c Interface Configuration Examples
DPT Port Adapter Configuration Example
DPT Interface Processor Configuration Example
IPS Options Configuration Example
DPT Topology Configuration Example
Basic APS Configuration Example
Multiple APS Interface Configuration Example
CSU/DSU Service Module Examples
2- and 4-Wire, 56/64-kbps Service Module Examples
E1-G.703/G.704 Serial Port Adapter Example
Low-Speed Serial Interface Examples
Synchronous or Asynchronous Mode Examples
Controlled-Carrier and Constant-Carrier Mode Examples
Cisco 4000 Series Router with 2T16S Serial Network Processor Example
Configuring Serial Interfaces
Use the information in this chapter to configure serial interfaces.
For information on configuring an ATM interface, refer to the "Configuring ATM Access over a Serial Interface" chapter in the Cisco IOS Wide-Area Networking Configuration Guide.
For hardware technical descriptions and information about installing interfaces, refer to the hardware installation and configuration publication for your product. For a complete description of serial interface commands used in this chapter, refer to the "Interface Commands" chapter of the Cisco IOS Interface Command Reference. To locate documentation of other commands that appear in this chapter, use the command reference master index or search online.
To identify the hardware platform or software image information associated with a feature, use the Feature Navigator on Cisco.com to search for information about the feature or refer to the software release notes for a specific release. For more information, see the Identifying Supported Platforms in "Using Cisco IOS Software."
This chapter includes the following sections:
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Configuring a High-Speed Serial Interface
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For examples of configuration tasks shown in this chapter, see the "Serial Interface Configuration Examples" section.
Configuring a High-Speed Serial Interface
The High-Speed Serial Interface (HSSI) Processor (HIP) provides a single HSSI network interface. The network interface resides on a modular interface processor that provides a direct connection between the high-speed CiscoBus and an external network.
The HSSI port adapters (PA-H and PA-2H) are available on:
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The PA-H provides one high-speed synchronous serial interface, and the PA-2H provides two high-speed synchronous serial interfaces that support full-duplex and data rates up to 52 Mbps. For more information on the PA-H, refer to the PA-H HSSI Port Adapter Installation and Configuration publication. For more information on the PA-2H, refer to the PA-2H Dual-Port HSSI Port Adapter Installation and Configuration publication.
The Cisco 3600 series 1-port HSSI network module provides full-duplex connectivity at SONET OC-1/STS-1 (51.840 MHz), T3 (44.736 MHz), and E3 (34.368 MHz) rates in conformance with the EIA/TIA-612 and EIA/TIA-613 specifications. The actual rate of the interface depends on the external data service unit (DSU) and the type of service to which it is connected. This 1-port HSSI network module can reach speeds of up to 52 Mbps in unidirectional traffic with 1548-byte packets and 4250 packets per second. ATM, High-Level Data Link Control (HDLC), PPP, Frame Relay, and Switched multimegabit Data Service (SMDS) WAN services are all fully supported.
Before you configure the 1-port HSSI network module, complete the following prerequisite tasks:
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HSSI Configuration Task List
To configure a HSSI interface perform the tasks in the following sections. Each task is identified as either required or optional.
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Specifying a HSSI
To specify a High-Speed Serial Interface (HSSI) and enter interface configuration mode, use one of the following commands in global configuration mode:
Router(config)# interface hssi number
Enters interface configuration.
Router(config)# interface hssi slot/port
Enters interface configuration for the Cisco 7500 series routers.
Specifying HSSI Encapsulation
The HSSI supports the serial encapsulation methods, except for X.25-based encapsulations. The default method is HDLC. To define the encapsulation method, use the following command in interface configuration mode:
Router(config-if)# encapsulation {atm-dxi | hdlc | frame-relay | ppp | sdlc-primary | sdlc-secondary | smds}
Configures HSSI encapsulation.
For information about PPP, refer to the "Configuring Asynchronous PPP and SLIP" and "Configuring Media-Independent PPP and Multilink PPP" chapters in the Cisco IOS Dial Services Configuration Guide.
Invoking ATM on a HSSI Line
If you have an ATM DSU, you can invoke ATM over a HSSI line. You do so by mapping an ATM virtual path identifier (VPI) and virtual channel identifier (VCI) to a Data Exchange Interface (DXI) frame address. ATM-DXI encapsulation defines a data exchange interface that allows a DTE (such as a router) and a DCE (such as an ATM DSU) to cooperate to provide a User-Network Interface (UNI) for ATM networks.
To invoke ATM over a serial line, use the following commands in interface configuration mode:
You can also configure the dxi map command on a serial interface.
To configure an ATM interface using an ATM Interface Processor (AIP) card, refer to the "Configuring ATM" chapter in the Cisco IOS Wide-Area Networking Configuration Guide.
Converting HSSI to Clock Master
The HSSI network module provides full-duplex connectivity at SONET OC-1/STS-1 (51.840 MHz), T3 (44.736 MHz), and E3 (34.368 MHz) rates in conformance with the EIA/TIA-612 and EIA/TIA-613 specifications. The actual rate of the interface depends on the DSU and the type of service to which it is connected. To convert the HSSI interface into a clock master use the following command in interface configuration mode:
Router(config-if)# hssi internal-clock
Converts the HSSI interface into a 51.84-MHz clock master.
Configuring a Synchronous Serial Interface
Synchronous serial interfaces are supported on various serial network interface cards or systems. These interfaces support full-duplex operation at T1 (1.544 Mbps) and E1 (2.048 Mbps) speeds. Refer to the Cisco Product Catalog for specific information regarding platform and hardware compatibility.
Synchronous Serial Configuration Task List
To configure a synchronous serial interface, perform the tasks in the following sections. Each task in the list is identified as either required or optional.
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See the "Serial Interface Configuration Examples" section for examples of configuration tasks described in this chapter.
Specifying a Synchronous Serial Interface
To specify a synchronous serial interface and enter interface configuration mode, use one of the following commands in global configuration mode:
Specifying Synchronous Serial Encapsulation
By default, synchronous serial lines use the High-Level Data Link Control (HDLC) serial encapsulation method, which provides the synchronous framing and error detection functions of HDLC without windowing or retransmission. The synchronous serial interfaces support the following serial encapsulation methods:
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To define the encapsulation method, use the following command in interface configuration mode:
Router(config-if)# encapsulation {atm-dxi | hdlc | frame-relay | ppp | sdlc-primary | sdlc-secondary | smds | stun | x25}
Configures synchronous serial encapsulation.
Encapsulation methods are set according to the type of protocol or application you configure in the Cisco IOS software.
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By default, synchronous interfaces operate in full-duplex mode. To configure an SDLC interface for half-duplex mode, use the following command in interface configuration mode:
Binary synchronous communication (Bisync) is a half-duplex protocol. Each block of transmission is acknowledged explicitly. To avoid the problem associated with simultaneous transmission, there is an implicit role of primary and secondary station. The primary sends the last block again if there is no response from the secondary within the period of block receive timeout.
To configure the serial interface for full-duplex mode, use the following command in interface configuration mode:
Router(config-if)# full-duplex
Specifies that the interface can run Bisync using switched RTS signals.
Configuring PPP
To configure PPP, refer to the "Configuring Media-Independent PPP and Multilink PPP" chapter in the Cisco IOS Dial Services Configuration Guide.
Configuring Half-Duplex and Bisync for Synchronous Serial Port Adapters on Cisco 7200 Series Routers
The synchronous serial port adapters (PA-8T-V35, PA-8T-X21, PA-8T-232, and PA-4T+) on Cisco 7200 series routers support half-duplex and Bisync. Bisync is a character-oriented data-link layer protocol for half-duplex applications. In half-duplex mode, data is sent one direction at a time. Direction is controlled by handshaking the Request to Send (RST) and Clear to Send (CTS) control lines. These are described in the following sections:
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For more information about the PA-8T-V35, PA-8T-X21, PA-8T-232, and PA-4T+ synchronous serial port adapters, refer to the following publications:
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Configuring Bisync
To configure the Bisync feature on the synchronous serial port adapters (PA-8T-V35, PA-8T-X21, PA-8T-232, and PA-4T+) on Cisco 7200 series routers, refer to the "Block Serial Tunnelling (BSTUN)" section of the "Configuring Serial Tunnel and Block Serial Tunnel" chapter of the Cisco IOS Bridging and IBM Networking Configuration Guide. All commands listed in the "Block Serial Tunnelling (BSTUN)" section apply to the synchronous serial port adapters on Cisco 7200 series routers. Any command syntax that specifies an interface number supports the Cisco 7200 series slot/port syntax.
Configuring Compression Service Adapters on Cisco 7500 Series Routers
The SA-Comp/1 and SA-Comp/4 data compression service adapters (CSAs) are available on:
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The SA-Comp/1 supports up to 64 WAN interfaces, and the SA-Comp/4 supports up to 256 WAN interfaces.
On the Cisco 7200 series routers you can optionally specify which CSA the interface uses to perform hardware compression.
You can configure point-to-point compression on serial interfaces that use PPP encapsulation. Compression reduces the size of a PPP frame via lossless data compression. PPP encapsulations support both predictor and Stacker compression algorithms.
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When you configure Stacker compression on Cisco 7200 series routers and on Cisco 7500 series routers, there are three methods of compression: hardware compression, distributed compression, and software compression. Specifying the compress stac command with no options causes the router to use the fastest available compression method, as described here:
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Using hardware compression in the CSA frees the main processor of the router for other tasks. You can also configure the router to use the VIP2 to perform compression by using the distributed option on the compress command, or to use the main processor of the router by using the software option on the compress command. If the VIP2 is not available, compression is performed in the main processor of the router.
When compression is performed in software installed in the main processor of the router, it might significantly affect system performance. You should disable compression in the router's main processor if the router CPU load exceeds 40 percent. To display the CPU load, use the show process cpu EXEC command.
For instructions on configuring compression over PPP, refer to the "Configuring Media-Independent PPP and Multilink PPP" chapter in the Cisco IOS Dial Services Configuration Guide.
Configuring Compression of HDLC Data
You can configure point-to-point software compression on serial interfaces that use HDLC encapsulation. Compression reduces the size of a HDLC frame via lossless data compression. The compression algorithm used is a Stacker (LZS) algorithm.
Compression is performed in software and might significantly affect system performance. We recommend that you disable compression if CPU load exceeds 65 percent. To display the CPU load, use the show process cpu EXEC command.
If the majority of your traffic is already compressed files, you should not use compression.
To configure compression over HDLC, use the following commands in interface configuration mode:
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Router(config-if)# encapsulation hdlc
Enables encapsulation of a single protocol on the serial line.
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Router(config-if)# compress stac
Enables compression.
Configuring Real-Time Transport Protocol Header Compression
Real-time Transport Protocol (RTP) is a protocol used for carrying packetized audio and video traffic over an IP network. RTP is described in RFC 1889, RTP—A Transport Protocol for Real-Time Applications. RTP is not intended for data traffic, which uses TCP or UDP (User Datagram Protocol). 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.
For information and instructions for configuring RTP header compression, refer to the "Configuring IP Multicast Routing" chapter in the Cisco IOS IP and IP Routing Configuration Guide.
Configuring Data Compression AIM
The data compression Advanced Interface Module (AIM) provides hardware-based compression and decompression of packet data transmitted and received on the serial network interfaces of the Cisco 2600 series router without occupying the Port Module Slot which might otherwise be used for additional customer network ports. Supported are the industry standard Lempel-Ziv Stac (LZS) and Microsoft point-to-point compression (MPPC) compression algorithms over point-to-point protocol (PPP) or Frame Relay. High-level Data Link Control (HDLC) is not supported. The data compression AIM requires Cisco IOS Release 12.0(1)T or later.
The data compression AIM is a daughtercard assembly that attaches directly to the Cisco 2600 motherboard leaving the single network module slot available for other purposes. The data compression AIM supports only serial interfaces using PPP encapsulation with STAC or MPPC compression, or Frame Relay encapsulation with STAC compression. No routing, bridging, or switching performance is impacted by this feature. The data compression AIM module contains a high-performance data compression coprocessor that implements the LZS and MPPC data compression algorithms. The module provides compression support for up to two E1 lines. The module contains a PCI Target/Initiator system bus interface for access into host system memory with minimal Host processor intervention.
To configure the data compression AIM daughtercard assembly, perform the following tasks:
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Configuring PPP Compression
Configure your Cisco 2600 access server to use PPP compression. Specify the following information for each serial interface:
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To configure the PPP form of compression, use the following commands, beginning in privileged EXEC mode:
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Router# configure terminal
Enters global configuration mode.
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Router(config)# interface serial slot/port
Enters interface configuration mode to configure serial interface 0 on port 0. If you have installed more than one WAN interface card, you have interfaces 0 and 1. Each WAN interface card has a pair of ports, 0 and 1.
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Router(config-if)# encapsulation ppp
Specifies the ppp encapsulation type.1
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Router(config-if)# compress {mppc stac} caim element-number
Specifies one of the algorithms (mppc, predictor, or stac) on the caim card for port 0.2
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Router(config-if)# no shutdown
Restarts the interface.
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Router(config-if)# Ctrl-Z
Returns to EXEC mode.
1 You also have the option of configuring encapsulation for Frame Relay.
2 You can also configure compression for another serial port or another CAIM card, depending upon your configuration.
Verifying PPP Compression
To check that the interface is activated, use the show interfaces serial slot/port command. Notice the highlighted fields in the following example:
Router# show interfaces serial 0/0Serial0/0 is up, line protocol is upHardware is PowerQUICC SerialInternet address is 1.1.1.2/24MTU 1500 bytes, BW 2000 Kbit, DLY 20000 usec,reliability 255/255, txload 3/255, rxload 50/255Encapsulation PPP, loopback not set, keepalive not setLCP OpenOpen: IPCP, CCP ==> If two routers have successfully negotiated compression.Last input 00:00:04, output 00:00:00, output hang neverLast clearing of "show interface" counters 1w1dQueueing strategy: fifoOutput queue 0/40, 80 drops; input queue 0/75, 0 drops30 second input rate 397000 bits/sec, 40 packets/sec30 second output rate 30000 bits/sec, 40 packets/sec27859655 packets input, 4176659739 bytes, 0 no bufferReceived 175145 broadcasts, 0 runts, 0 giants, 0 throttles0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort55309592 packets output, 1044865717 bytes, 0 underruns0 output errors, 0 collisions, 12 interface resets0 output buffer failures, 0 output buffers swapped out36 carrier transitionsDCD=up DSR=up DTR=up RTS=up CTS=upTo indicate whether compression is active, use the show compress command. Notice the highlighted fields in the following example:
Router# show compressSerial0/0Hardware compression enabledCSA in slot 0 in useCompressed bytes sent: 317862131 bytes 61 Kbits/sec ratio: 12.870Compressed bytes recv: 221975672 bytes 43 Kbits/sec ratio: 9.194restarts: 1last clearing of counters: 41252 seconds
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Configuring Frame Relay Map Compression
Configure Frame Relay to map compression on this Data-Link Connection Identifier (DLCI) to use the specified AIM hardware compression on the Cisco 2600 access server. You must specify the following information for each serial interface:
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You must also designate the CAIM daughtercard as a source of this algorithm, and the CAIM element number.
To configure the Frame Relay map compression command for operation, use the following commands beginning in privileged EXEC mode:
Step 1
Router# configure terminal
Enters global configuration mode.
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Router(config)# interface serial slot/port
Enters interface configuration mode to configure the serial interface. If you have installed more than one WAN interface card, you have interfaces 0 and 1. Each WAN interface card has a pair of ports, 0 and 1.
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Router(config-if)# encapsulation frame-relay
Specifies Frame Relay encapsulation.1
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Router(config-if)# frame-relay map ip ip-address dlci-number broadcast payload-compression frf9 stac caim element-number
Specifies the stac algorithm on the CAIM card for the port.2
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Router(config-controller)# no shutdown
Restarts the interface.
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Router(config-if)# Ctrl-Z
Returns to EXEC mode.
1 You also have the option of configuring encapsulation for PPP.
2 You can also configure compression for another serial port or another CAIM card, depending upon your configuration.
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Verifying Frame Relay Map Compression
To check that the interface is activated with proper compression and encapsulation, use the show interfaces serial slot/port command. Notice the highlighted fields in the following example:
Router# show interfaces serial 0/1Serial0/1 is up, line protocol is upHardware is PowerQUICC SerialInternet address is 1.1.1.2/24MTU 1500 bytes, BW 2000 Kbit, DLY 20000 usec,reliability 255/255, txload 1/255, rxload 1/255Encapsulation FRAME-RELAY, loopback not set, keepalive not setFR SVC disabled, LAPF state downBroadcast queue 0/64, broadcasts sent/dropped 2743/0, interface broadcasts 2742Last input 03:05:57, output 00:00:03, output hang neverLast clearing of "show interface" counters 1w1dQueueing strategy: fifoOutput queue 0/40, 80 drops; input queue 0/75, 0 drops30 second input rate 0 bits/sec, 0 packets/sec30 second output rate 0 bits/sec, 0 packets/sec30800054 packets input, 3488155802 bytes, 0 no bufferReceived 199567 broadcasts, 0 runts, 0 giants, 0 throttles2 input errors, 0 CRC, 2 frame, 0 overrun, 0 ignored, 0 abort58246738 packets output, 1325052697 bytes, 0 underruns0 output errors, 0 collisions, 15 interface resets0 output buffer failures, 0 output buffers swapped out36 carrier transitionsDCD=up DSR=up DTR=up RTS=up CTS=upTo indicate whether compression is active, use the show controllers serial 1/0 command. Notice the highlighted fields in the following example:
Router# show controllers serial 1/0CD2430 Slot 1, Port 0, Controller 0, Channel 0, Revision 14Channel mode is synchronous serialidb 0x811082E8, buffer size 1524, X.21 DTE cableGlobal registersrpilr 0x2, rir 0x0, risr 0x0, rfoc 0x0, rdr 0x30tpilr 0x1, tir 0x0, tisr 0x60, tftc 0x0, tdr 0x41mpilr 0x3, mir 0x2, misr 0x60bercnt 0xFF, stk 0x0Per-channel registers for channel 0Option registers0x02 0x00 0x42 0xE7 0xE0 0x00 0x00Command and status registerscmr 0xC0, ccr 0x00, csr 0xAC, msvr-rts 0xF1, msvr-dtr 0xF1Clock option registersrcor 0x06, rbpr 0x01, tcor 0xC8, tbpr 0x01Interrupt registersier 0x89, livr 0x00, licr 0x00DMA buffer status 0x27DMA receive registersarbaddr 0x2549D44, arbcnt 1548, arbsts 0x1brbaddr 0x2548344, brbcnt 1548, brbsts 0x1rcbaddr 0x2549D94DMA transmit registersatbaddr 0x257F93E, atbcnt 104, atbsts 0x43btbaddr 0x25B25C2, btbcnt 1490, btbsts 0x43tcbaddr 0x25B25D2Special character registersschr1 0x00, schr2 0x00, schr3 0x00, schr4 0x00scrl 0x0, scrh 0x0, lnxt 0xF1Driver context informationContext structure 0x8110D830, Register table 0x40800400Serial Interface Control 5:1 Register (0x40800802) is 0x0Adaptor Flags 0x0Serial Modem Control Register (0x40800804) is 0x18Receive static buffer 0x810E1274Receive particle buffers 0x8110DE00, 0x8110DDC0Transmit DMA buffers 0x8113E240, 0x810F2808, 0x810D4C00, 0x810EA0DCTransmit packet with particles 0x0, first word is 0x0Interrupt rates (per second) transmit 25, receive 139, modem 0True fast-switched packets 41Semi fast-switched packets 13449573Transmitter hang count 0Residual indication count 0Bus error count 0Aborted short frames count 0CRC short frames count 0Error countersCTS deassertion failures 0Nested interrupt errors transmit 0, receive 0, modem 0Using Compression AIM 0CompressionAim0ds:0x8113FC04 idb:0x8113A6CC5005867 uncomp paks in --> 5005867 comp paks out38397501 comp paks in --> 38397502 uncomp paks out2882277146 uncomp bytes in--> 497476655 comp bytes out3500965085 comp bytes in --> 1211331227 uncomp bytes out72 uncomp paks/sec in--> 72 comp paks/sec out557 comp paks/sec in --> 557 uncomp paks/sec out334959 uncomp bits/sec in--> 57812 comp bits/sec out406855 comp bits/sec in --> 140827 uncomp bits/sec out68841 seconds since last clearholdq:0 hw_enable:1 src_limited:0 num cnxts:8no data:0 drops:0 nobuffers:0 enc adj errs:0 fallbacks:5322165no Replace:0 num seq errs:0 num desc errs:0 cmds complete:43403738Bad reqs:0 Dead cnxts:0 No Paks:0 enq errs:0rx pkt drops:0 tx pkt drops:0 dequeues:0 requeues:0drops disabled:0 clears:0 ints:41973007 purges:203200no cnxts:0 bad algos:0 no crams:0 bad paks:0# opens:0 # closes:4 # hangs:0# 9711 fatal:0 # poison pkts:0 cmd/res ovruns:0# dma fatal:0Jupiter DMA Controller Registers:(0x40200000Cmd Ring:0x025BAE60 Src Ring:0x025BBB60Res Ring:0x025BB4E8 Dst Ring:0x025BBDA8Status/Cntl:present:0x8080989C last int:0x9898989CInten:0x30302021 config:0x00080003Num DMA ints:41973355Hifn9711 Data Compression Coprocessor Registers (0x40201000):Config:0x000051D4 Inten:0x00000E00Status:0x00004000 FIFO status:0x00004000FIFO config:0x00000101
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Configuring Frame Relay Payload Compression
To configure Frame Relay payload compression, use the following commands beginning in privileged EXEC mode:
Step 1
Router# configure terminal
Enters global configuration mode.
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Router(config)# interface serial slot/port
Enters interface configuration mode to configure the specified serial interface and port.
Step 3
Router(config-if)# encapsulation ppp
Specifies ppp encapsulation type.1
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Router(config-if)# frame-relay payload-compression frf9 stac
caim element-number
Specifies the stac algorithm on the CAIM card for the specified port.2
Step 5
Router(config-if)# no shutdown
Restarts the interface.
Step 6
Router(config-if)# Ctrl-Z
Returns to EXEC mode.
1 You also have the option of configuring encapsulation for Frame Relay.
2 You can configure compression for any serial port or another CAIM card, depending upon your configuration.
Verifying Frame Relay Payload Compression
To check that the interface is activated with proper compression and encapsulation, use the show interfaces serial slot/port command. Notice the highlighted fields in the following example:
Router# show interfaces serial 0/0Serial0/0 is up, line protocol is upHardware is PowerQUICC SerialInternet address is 1.1.1.2/24MTU 1500 bytes, BW 2000 Kbit, DLY 20000 usec,reliability 255/255, txload 1/255, rxload 1/255Encapsulation FRAME-RELAY, loopback not set, keepalive not setFR SVC disabled, LAPF state downBroadcast queue 0/64, broadcasts sent/dropped 2743/0, interface broadcasts 2742Last input 03:05:57, output 00:00:03, output hang neverLast clearing of "show interface" counters 1w1dQueueing strategy: fifoOutput queue 0/40, 80 drops; input queue 0/75, 0 drops30 second input rate 0 bits/sec, 0 packets/sec30 second output rate 0 bits/sec, 0 packets/sec30800054 packets input, 3488155802 bytes, 0 no bufferReceived 199567 broadcasts, 0 runts, 0 giants, 0 throttles2 input errors, 0 CRC, 2 frame, 0 overrun, 0 ignored, 0 abort58246738 packets output, 1325052697 bytes, 0 underruns0 output errors, 0 collisions, 15 interface resets0 output buffer failures, 0 output buffers swapped out36 carrier transitionsDCD=up DSR=up DTR=up RTS=up CTS=up
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Configuring Diagnostics
Configure the AIM daughtercard to provide compression for the Cisco 2600 series router. You must specify the following information for each daughtercard installed.
To configure the PPP for compression, use the following commands beginning in user EXEC mode:
Verifying Diagnostics
To check that the data compression AIM is collecting statistics that represent proper compression, use the show pas caim element-number command:
Router# show pas caim stats 0CompressionAim0ds:0x80F56A44 idb:0x80F50DB8422074 uncomp paks in --> 422076 comp paks out422071 comp paks in --> 422075 uncomp paks out633912308 uncomp bytes in--> 22791798 comp bytes out27433911 comp bytes in --> 633911762 uncomp bytes out974 uncomp paks/sec in--> 974 comp paks/sec out974 comp paks/sec in --> 974 uncomp paks/sec out11739116 uncomp bits/sec in--> 422070 comp bits/sec out508035 comp bits/sec in --> 11739106 uncomp bits/sec out433 seconds since last clearholdq: 0 hw_enable: 1 src_limited: 0 num cnxts: 4no data: 0 drops: 0 nobuffers: 0 enc adj errs: 0 fallbacks: 0no Replace: 0 num seq errs: 0 num desc errs: 0 cmds complete: 844151Bad reqs: 0 Dead cnxts: 0 No Paks: 0 enq errs: 0rx pkt drops: 0 tx pkt drops: 0 dequeues: 0 requeues: 0drops disabled: 0 clears: 0 ints: 844314 purges: 0no cnxts: 0 bad algos: 0 no crams: 0 bad paks: 0# opens: 0 # closes: 0 # hangs: 0To identify compression characteristics for each port, use the show compress command:
Router# show compressSerial0/0Hardware compression enabledCSA in slot 0 in useCompressed bytes sent: 317862131 bytes 61 Kbits/sec ratio: 12.870Compressed bytes recv: 221975672 bytes 43 Kbits/sec ratio: 9.194restarts: 1last clearing of counters: 41252 secondsSerial0/1Hardware compression enabledCSA in slot 0 in useCompressed bytes sent: 249720 bytes 0 Kbits/sec ratio: 5.923Compressed bytes recv: 465843659 bytes 43 Kbits/sec ratio: 9.128restarts: 1last clearing of counters: 85525 secondsTo reset the CAIM hardware to 0, use the clear compress command. There is no output for this command; instead, check the output from the show compress command to verify the result:
Router# clear compressRouter# show compressSerial0/0Hardware compression enabledCSA in slot 0 in useCompressed bytes sent: 0 bytes 61 Kbits/sec ratio: 0Compressed bytes recv: 0 bytes 43 Kbits/sec ratio: 0restarts: 0last clearing of counters: 0 seconds
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Configuring the CRC
The cyclic redundancy check (CRC) on a serial interface defaults to a length of 16 bits. To change the length of the CRC to 32 bits on an Fast Serial Interface Processor (FSIP) or HSSI Interface Processor (HIP) of the Cisco 7500 series only, use the following command in interface configuration mode:
Using the NRZI Line-Coding Format
The nonreturn-to-zero (NRZ) and nonreturn-to-zero inverted (NRZI) formats are supported on:
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NRZ and NRZI are line-coding formats that are required for serial connections in some environments. NRZ encoding is most common. NRZI encoding is used primarily with EIA/TIA-232 connections in IBM environments.
The default configuration for all serial interfaces is NRZ format. The default is no nrzi-encoding.
To enable NRZI format, use one of the following commands in interface configuration mode:
Enabling the Internal Clock
When a DTE does not return a transmit clock, use the following interface configuration command on the Cisco 7000 series to enable the internally generated clock on a serial interface:
Router(config-if)# transmit-clock-internal
Enables the internally generated clock on a serial interface.
Inverting the Data
If the interface on the PA-8T and PA-4T+ synchronous serial port adapters is used to drive a dedicated T1 line that does not have B8ZS encoding, you must invert the data stream on the connecting CSU/DSU or on the interface. Be careful not to invert data on both the CSU/DSU and the interface because two data inversions will cancel each other out.
If the T1 channel on the CT3IP is using alternate mark inversion (AMI) line coding, you must invert the data. For more information, refer to the t1 linecode controller configuration command. For more information on the CT3IP, see the "Configuring a Channelized T3 Interface Processor" section.
To invert the data stream, use the following command in interface configuration mode:
Inverting the Transmit Clock Signal
Systems that use long cables or cables that are not transmitting the TxC signal (transmit echoed clock line, also known as TXCE or SCTE clock) can experience high error rates when operating at the higher transmission speeds. For example, if the interface on the PA-8T and PA-4T+ synchronous serial port adapters is reporting a high number of error packets, a phase shift might be the problem. Inverting the clock signal can correct this shift. To invert the clock signal, use the following commands in interface configuration mode:
Settin
