Table of Contents

Feature Overview

Benefits
Restrictions
Related Features and Technologies
Related Documents

Supported Platforms
Supported Standards, MIBs, and RFCs
Prerequisites
Configuration Tasks

Configuring the Remote Routers

Specifying the ALPS Local Peer IP Address
Specifying the ALPS Remote Peer IP Address
Specifying the ALPS Circuit
Specifying Each ASCU

Configuring the Data Center Router

Specifying the ALPS Host Local Peer Address
Specifying AX.25
Specifying EMTOX

Customizing the Service Messages
Customizing the Alarm Notifications
Updating a Circuit
Verifying ALPS

Monitoring and Maintaining ALPS
Configuration Examples

ALPS with MATIP Configuration for ALC and UTS Example
ALPS Configuration for ALC and AX.25 Example
ALPS Configuration for UTS and EMTOX Example

Command Reference
alps ascu
alps auto-reset
alps service-msg-list number
alps service-msg data-drop
alps service-msg format
alps service-msg status-change
alps t1
show alps ascu
Debug Commands
debug alps ascu
debug alps snmp
Glossary

Airline Product Set Enhancements

This feature module describes the Airline Product Set (ALPS) Enhancements feature. It includes information on the overview and benefits of the new feature, configuration tasks, configuration examples, and new and modified commands.

This document contains the following sections:

• Feature Overview

• Supported Platforms

• Supported Standards, MIBs, and RFCs

• Prerequisites

• Configuration Tasks

• Monitoring and Maintaining ALPS

• Configuration Examples

• Command Reference

• Debug Commands

• Glossary

Feature Overview

The ALPS Enhancements feature in Cisco IOS Release 12.1(2)T introduces additions to the ALPS service messages and extensions to the ALPS P1024B Airline Control (ALC) protocol support. This feature includes customized options to configure the format, address, and transmission of service messages. The ALPS ALC support is extended to be more scalable. The ALPS ASCU debug support is extended to include trace capability for the six-bit International Programmable Airline Reservation System (IPARS) format. This feature is an enhancement to the existing ALPS technology.

ALPS Background Information

ALPS is a tunneling mechanism that transports airline protocol data across a Cisco router-based TCP/IP network to a mainframe. This feature provides connectivity between agent set control units (ASCUs) and a mainframe host that runs the airline reservation system.

The ALPS feature was released in three phases. The first two phases of ALPS enabled the network migration to TCP/IP without requiring any changes in the hardware or software of the endstations (ASCUs and mainframes). ALPS phase I and II implemented a new protocol, ALPS Tunneling Protocol (ATP), to tunnel airline protocol traffic (P1024B Airline Control [ALC] or P1024C Universal Terminal Support [UTS] data) through the TCP/IP network between peer Cisco routers. ALPS phase I provided support for the ALC protocol and the transport of the data from the ASCUs to a reservations system on an IBM mainframe. ALPS phase II provided support for the UTS protocol and the transport of the data from the ASCUs to a reservations system on a UNISYS host system.

Figure 1 shows a basic ALPS topology with ALC, UTS, Airline X.25 (AX.25) and Exchange of Mixed Traffic over X.25 (EMTOX) switched virtual circuit (SVC) protocols. Three major components provide the end-to-end transportation of airline protocol traffic across the network: the P1024B ALC or P1024C UTS protocol, the TCP-based transport protocol, and the AX.25/EMTOX access to the mainframe.

ALPS phase III provided support for Mapping of Airline Traffic over Internet Protocol (MATIP). MATIP is an industry standard protocol for transporting airline protocol traffic across a TCP/IP network. ALPS phase III enables the end-to-end delivery of ALC and UTS data streams between a Cisco router and the mainframe using TCP/IP. ALPS with MATIP removes the X.25 (AX.25 or EMTOX) requirements for communication with the host reservation system by enabling TCP/IP communication between the router and the airline host reservation system.

Figure 2 shows the basic ALPS topology and the MATIP architecture implemented in Phase III. Three major components provide the end-to-end transportation of airline protocol traffic across the network: the P1024B ALC or P1024C UTS protocol, the TCP/IP-based MATIP protocol conversion, and the TCP/IP access to the mainframe.

Benefits

In Cisco IOS Release 12.1(2)T, ALPS includes the following debug, ALC, and service message enhancements.

Debug Enhancement

The ALPS ASCU debug support additions provide new capabilities that enable you to:

• Display debug alps ascu command trace output in IPARS format

ALC Enhancements

The ALPS ALC protocol stack includes the following extensions:

• Automatic ASCU reset

• T1 timer range increase

• Modification of the accepted ASCU IA value list

Service Message Enhancements

The additions to the ALPS service messages provide new capabilities that enable you to:

• Specify sita or apollo service message format

• Disable the forwarding of ALPS circuit status change service messages

• Specify where to retrieve the terminal address for dropped-data service messages

• Disable specific service messages

• Configure service message text with an increased character length

Restrictions

The ALPS Enhancements feature supports only type A conversational protocol traffic. The ALPS Enhancements feature does not support MATIP type A host-to-host protocol traffic and MATIP type B messaging protocol traffic.

Remote routers must have the Cirrus Logic CD2430 chipset on a synchronous serial interface module to connect to the ALC or UTS ASCUs. See the "Supported Platforms" section for more information.

Related Features and Technologies

The ALPS Enhancements feature is an enhancement to the existing ALPS features that are documented in the "Airline Product Set" chapters of the Cisco IOS Release 12.1 Bridging and IBM Networking Configuration Guide and the Cisco IOS Release 12.1 Bridging and IBM Networking Command Reference, Volume I.

Related Documents

• Cisco IOS Release 12.1 Bridging and IBM Networking Configuration Guide

• Cisco IOS Release 12.1 Bridging and IBM Networking Command Reference, Volume I

• Cisco IOS Release 12.1 Configuration Fundamentals Configuration Guide

• Cisco IOS Release 12.1 Configuration Fundamentals Command Reference

• Cisco IOS Release 12.1 Interface Configuration Guide

• Cisco IOS Release 12.1 Interface Command Reference

Supported Platforms

Remote routers must have the Cirrus Logic CD2430 chipset on a synchronous serial interface module to connect to the ALC or UTS ASCUs. The CD2430 chipset is supported on the following router platforms:

• Cisco 2520, 2521, 2522, and 2523

• Cisco 2600 series

• Cisco 3600 series

• Cisco 4500

• Cisco 4700

---

Note The Cisco 4500 and Cisco 4700 platforms must have a high-density, low-speed serial card installed. Sixteen low-speed ports are available for performing the remote router functions.

---

Supported Standards, MIBs, and RFCs

Standards

• P1024B Communication Control Protocol Specification, Societe Internationale de Telecommunications Aeronautiques

• P1024C Communication Control Protocol Specification, Societe Internationale de Telecommunications Aeronautiques

• MATIP Implementation Guide, Societe Internationale de Telecommunications Aeronautiques

MIBs

The ALPS Enhancement feature supports the CISCO-ALPS-MIB and the following MIB enhancements:

• Extensions to the alpsIfP1024Table

• Extension to the alpsAscuTable

• Addition of Simple Network Management Protocol (SNMP) notifications for ALPS circuit open request failure and ALPS circuit open request with a partial rejection

For descriptions of supported MIBs and how to use them, see the Cisco MIB web site on CCO at http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.

RFCs

• RFC 2351, Mapping of Airline Reservation, Ticketing, and Messaging Traffic over IP, May 1998

Prerequisites

The ALPS Enhancements feature is available on the Cisco IOS software IP Plus images.

Configuration Tasks

See the following sections for configuration tasks for the ALPS Enhancements feature. Each task in the list indicates if the task is optional or required. The tasks in the "Configuring the Remote Routers" section are the only required tasks for ALPS with MATIP.

For a complete description of the new or modified ALPS commands in this feature module, refer to the "Command Reference" section. For a complete description of the rest of the ALPS commands in this feature module, refer to the "Airline Product Set Configuration Commands" chapter in the Cisco IOS Bridging and IBM Networking Command Reference, Volume I. To locate documentation of other commands that appear in this feature module, use the command reference master index or search online.

• Configuring the Remote Routers (Required)

• Configuring the Data Center Router (Required for EMTOX and AX.25, only)

• Customizing the Service Messages (Optional)

• Customizing the Alarm Notifications (Optional)

• Updating a Circuit (Optional)

• Verifying ALPS (Required)

See the "Configuration Examples" section for more information.

Configuring the Remote Routers

Note To configure ALPS with MATIP, you must perform the following tasks, only. The tasks apply to EMTOX and AX.25, also.

Perform the tasks in the following sections to configure the ALPS Enhancements feature on the remote routers:

• Specifying the ALPS Local Peer IP Address

• Specifying the ALPS Remote Peer IP Address

• Specifying the ALPS Circuit

• Specifying Each ASCU

Specifying the ALPS Local Peer IP Address

You must identify an IP address as an ALPS local peer on the remote router. Only one ALPS local peer is permitted on a router.

To specify the ALPS local peer IP address, use the following commands in global configuration mode:

	Command	Purpose
Step 1	Router(config)# alps local-peer ipaddress [promiscuous]	Specifies an IP address to use as the ALPS local peer on the remote router.
Step2	Router(config)# alps keepalive [interval time] [retry count]	Enables TCP keepalives for ALPS TCP peer connections.

Specifying the ALPS Remote Peer IP Address

You must specify a partner IP address (remote peer) on the remote router. The peer connection may be permanent or dynamic (established on demand). You can configure an ATP connection to be permanent or dynamic by configuring the optional dynamic keyword.

NoteMATIP sessions are dynamic, whether or not the dynamic keyword is configured. To simulate a permanent connection in MATIP, configure the dynamic keyword with an inact-timer value of zero.

To specify the partner IP address for one or more TCP peer connections to the configured IP address, use the following command in global configuration mode:

Command	Purpose
Router(config)# alps remote-peer ip-addr [protocol {atp | matip-a}] [status-interval interval] [status-retry retries] [dynamic [inact-timer] [no-circuit no-circ-timer]] [tcp-qlen [num]]	Specifies the partner IP address. If you select the ATP protocol, you must configure the data center routers.

Specifying the ALPS Circuit

An ALPS circuit is a communication path across a TCP connection for one or more ASCUs. The ALPS circuit must have a configured association with an ALPS remote peer to establish a connection to the host. Additionally, an ALPS circuit configuration can specify a different remote peer as a backup peer to the host. Each MATIP circuit maps to a single TCP connection. For ATP, ALPS circuits can be multiplexed across to a single TCP connection.

To specify an ALPS circuit, use the following commands, beginning in global configuration mode:

	Command	Purpose
Step1	Router(config)# alps circuit name	Specifies an ALPS circuit at the remote router and enters ALPS circuit submode.
Step2	Router(config-alps-circ)# alps primary-peer ip-addr [backup-peer ip-addr]	Specifies the primary TCP peer and an optional backup peer for this ALPS circuit.
Step3	Router(config-alps-circ)# alps local-hld loc-hld remote-hld rem-hld	Specifies the local high-level designator (HLD) for this ALPS circuit. The remote-hld keyword is not applicable for ALPS with MATIP. The loc-hld is the hld of the device that is being replaced. The rem-hld is the hld of the host mainframe.
Step4	Router(config-alps-circ)# alps hostlink number {ax25 lcn | emtox x121-addr} [winout val1] [winin val2] [ops val3] [ips val4]	Specifies information required to establish an X.25 virtual circuit at the central CPE.
Step5	Router(config-alps-circ)# alps connection-type permanent [retry-timer]	(Optional) Specifies that this circuit should be established when the circuit is enabled.
Step6	Router(config-alps-circ)# alps lifetime-timer timer	(Optional) Specifies how long messages can be queued in the ALPS circuit queue.
Step7	Router(config-alps-circ)# alps service-msg-interval seconds	(Optional) Specifies the interval between the transmission of a service message to an ASCU and the transmission of a PLEASE RETRY message. The PLEASE RETRY message is transmitted only to ASCUs that use circuits with a dynamic connection type.
Step8	Router(config-alps-circ)# alps service-msg-list list	(Optional) Defines the service message list to be used for this circuit.
Step9	Router(config-alps-circ)# alps matip-close-delay time	(Optional) Specifies the interval between the closing and reopening of the MATIP circuit connection.
Step10	Router(config-alps-circ)# alps idle-timer timer	(Optional) Specifies (for dynamic circuits) the length of time that can elapse before an idle circuit is disabled.
Step11	Router(config-alps-circ)# alps mpx {group | single} hdr {a1a2 | none}	(Optional) Specifies the multiplexing and the ASCU identification header for this circuit.
Step12	Router(config-alps-circ)# alps enable-circuit	Enables the circuit.

Specifying Each ASCU

You must configure each ASCU within the context of the serial interface configuration. You must configure ASCU addressing information and association with an ASCU. You can configure the timers, maximum frame sizes, and retry values optional configuration parameters for each ASCU. Appropriate default parameters are used for unspecified parameters. Once you configure the first ASCU, you can configure additional ASCUs using only Steps 8 through 17.

To specify an ASCU, use the following commands, beginning in global configuration mode:

	Command	Purpose
Step1	Router(config)# interface type number	Configures an interface and enters interface configuration mode.
Step2	Router(config-if)# encapsulation [alc | uts]	Specifies the protocol to be used on the serial interface.
Step3	Router(config-if)# alps t1 delay	(Optional) Specifies the timeout delay between the transmission of an ALC poll message and the receipt of the first character of the poll message response.
Step4	Router(config-if)# alps t2 delay	(Optional---ALC only) Specifies the timeout delay between receipt of the first character of the response to a poll message and the receipt of a Go Ahead message. Applies to ALC, only.
Step5	Router(config-if)# alps n1 errors	(Optional) Specifies the threshold of consecutive errors logged before an ASCU is declared down.
Step6	Router(config-if)# alps n2 polls	(Optional) Specifies the number of polls that must be correctly replied to before an ASCU is declared up.
Step7	Router(config-if)# alps n3 value	(Optional---UTS only) Specifies the maximum number of retransmissions of an unacknowledged output data message to an ASCU. Applies to UTS, only.
Step8	Router(config-if)# alps servlim polls	(Optional) Specifies the number of cycles of the active poll list to execute before polling the next ASCU on the inactive poll list.
Step9	Router(config-if)# transmitter-delay delay	Specifies number of padding characters added to the end of the frame (minimum dead-time after transmitting a packet).
Step10	Router(config-if)# half-duplex	Specifies half-duplex mode on an SDLC interface or on the FDDI full-duplex, single-mode port adapter and FDDI full-duplex, multimode port adapter on the Cisco 7200 series and Cisco 7500 series routers. NoteALPS supports the serial interface commands that are available if half-duplex mode is specified. This support applies to an interface that is configured as data circuit-terminating equipment (DCE) and data terminal equipment (DTE).
Step11	Router(config-if)# alps poll-pause msec	(Optional) Specifies the minimum interval, in milliseconds, between initiations of the polling cycle.
Step12	Router(config-if)# alps service-msg data-drop {msg-term | config-term}	(Optional) Specifies where to retrieve the terminal address to use when a service message is sent to an ASCU as a result of a dropped data message from a terminal.
Step13	Router(config-if)# alps service-msg format {sita | apollo}	(Optional) Specifies the protocol format of service messages sent from the router to an ASCU.
Step14	Router(config-if)# alps service-msg status-change	(Optional) Specifies that ALPS circuit status change service messages will be sent to ASCUs on the serial interface.
Step15	Router(config-if)# alps ascu id	Specifies a physical ASCU identity (the ASCU interchange address value for ALC) and enters ALPS ASCU submode.
Step16	Router(config-alps-ascu)# alps default-circuit name	Specifies the ALPS circuit that this ASCU uses.
Step17	Router(config-alps-ascu)# alps a1-map a1-value a2-map a2-value	Specifies the A1 and A2 logical ASCU identification information.
Step18	Router(config-alps-ascu)# alps retry-option [resend | reenter]	(Optional) Specifies the retry option when an ALC message with a bad cyclic check character (CCC) is received.
Step19	Router(config-alps-ascu)# alps max-msg-length value	(Optional) Specifies maximum input message length.
Step20	Router(config-alps-ascu)# alps error-display number1 number2	(Optional) Specifies where error messages are displayed: For P1024B ALC, the number1 argument specifies the terminal address (TA) where these service messages are sent and the number2 argument specifies the screen line number where service messages are displayed. For P1024C UTS, the number1 argument specifies the screen line number where service messages are displayed and number2 argument specifies the column number where service messages are displayed.
Step21	Router(config-alps-ascu)# alps auto-reset	(Optional) Automatically resets non-responsive ALC ASCUs in the DOWN state.
Step22	Router(config-alps-ascu)# alps enable-ascu	Polls the ASCU.

Configuring the Data Center Router

NoteThese tasks apply to EMTOX and AX.25, only.

Perform the tasks in the following sections to configure the ALPS Enhancements feature on the data center router:

• Specifying the ALPS Host Local Peer Address

• Specifying AX.25

• Specifying EMTOX

Specifying the ALPS Host Local Peer Address

You must identify an IP address to use as the ALPS local peer IP address. Only one ALPS host local peer is permitted on a router. The promiscuous option, which allows any remote router to connect, is recommended at the central CPE.

To specify the ALPS host local peer address, use the following command in global configuration mode:

Command	Purpose
Router(config)# alps local-peer ip-address [promiscuous]	Specifies the IP address of the local peer.

Specifying AX.25

To enable AX.25 on an X.25 interface, the ALPS host HLD and hostlink number must be configured and AX.25 must be specified on an X.25 serial interface. At circuit-establishment time, the remote router forwards the host HLD, the logical channel number (LCN), and the hostlink number for the permanent virtual circuit (PVC), to be used for the ASCU group.

To configure AX.25 on an X.25 interface, use the following commands beginning in global configuration mode:

	Command	Purpose
Step1	Router(config)# interface type number	Configures an interface and enters interface configuration mode.
Step2	Router(config-if)# encapsulation x25	Specifies a serial interface as an X.25 device.
Step3	Router(config-if)# alps host-hld hld host-link num {{ax25 [damp-tmr value]} | {emtox x.121 [pseudo-conv]}} [life-tmrvalue]	Enables ALPS on the X.25 interface.

Specifying EMTOX

To enable EMTOX on an X.25 interface, the host HLD and the hostlink number must be configured and EMTOX must be specified on an X.25 serial interface. At circuit-establishment time, the remote router forwards the X.121 address to be used as the calling address in the X.25 call and the host HLD and the hostlink number. If the host performs a call out, a correlation between the X.121 called address and a remote router peer IP address must be configured.

To configure EMTOX on an X.25 interface, use the following commands beginning in global configuration mode:

	Command	Purpose
Step1	Router(config)# interface type number	Configures an interface and enters interface configuration mode.
Step2	Router(config-if)# encapsulation x25	Specifies a serial interface as an X.25 device.
Step3	Router(config-if)# alps host-hld hld host-link num {{ax25 [damp-tmr value]} | {emtox x.121 [pseudo-conv]}} [life-tmrvalue]	Enables ALPS on the X.25 interface.
Step4	Router(config-if)# alps translate x.121-addr ip-addr	Maps an X.121 address to an IP address on a remote peer.

Customizing the Service Messages

You can customize the contents of the service messages and service message list. To specify the service message number and the content of the message, use the following command in global configuration mode:

Command	Purpose
Router(config)# alps service-msg-list list number number msg	Specifies service message numbers and content.

NoteThe default service message is used if no service message list number is specified. If you configure a particular service message on a list, the default service message still is used for the rest of the messages on that list.

NoteOnce the alps service-msg-list number command has been configured, you can define the service message list to be used on the circuit by configuring the alps service-msg-list command.

NoteYou can configure the handling of service messages using the alps service-msg data-drop, alps service-msg format, and alps service-msg status-change interface configuration-level commands.

Table 1 shows the default service message text strings:

Table1: Service Message Default Text Strings

Message Number	Event	Text String
1	ALPS circuit to host is opened.	CONNECTION UP
2	X.25 virtual circuit at the host has been cleared.	DISC BY THE HOST
3	X.25 interface at the host is down.	HOST ISOLATED
4	No response from the host router when trying to establish a connection.	NETWORK PROBLEM
5	Connection to host was disconnected because of inactivity.	READY TO CONNECT
6	Network is congested.	CONGESTION
7	Network congestion has cleared.	PLEASE PROCEED
8	Network operator has disabled the path to the host.	DISC BY NET OPERAT

Customizing the Alarm Notifications

You can enable and customize alarms (error messages) and SNMP traps. To enable and customize alarms for the ALPS ASCUs, circuits, or peers, use the following commands in global configuration mode:

Command	Purpose
Router(config)# alps enable-alarms ascu [interface id]	Enables alarms for the ALPS ASCUs.
Router(config)# alps enable-alarms circuit [name]	Enables alarms for the ALPS circuits.
Router(config)# alps enable-alarms peer [ip-address]	Enables alarms for the ALPS peers.

Updating a Circuit

You can clear or update the circuits on the ALPS network. If a specific name is entered, the update action will be executed only on a configured circuit with that name; otherwise, the action will be performed on all configured circuits. If the circuit uses the ATP protocol, an update consists of a closing and re-opening of the ALPS circuit (the same action performed when clearing the circuit). If the circuit is a MATIP circuit, the update results in the sending of a configuration update (in the form of a MATIP Session Open command). You can update the circuit only on enabled or active (opened or opening state) ALPS circuits.

To update one or more ALPS circuits, use the following command in EXEC mode:

Command	Purpose
Router# alps update-circuit [name]	Specifies name of circuit to update.

Verifying ALPS

Perform the tasks in the following steps to verify the components of the ALPS network:

router# show alps ascu
interface    dlc   id   a1   a2   circuit    pkt_tx  pkt_rx  state
-------------------------------------------------------------------------------------
Serial6      ALC   42   60   70   CKT_ALC_1  416     416     UP
Serial6      ALC   45   60   72   CKT_ALC_1  600     600     UP
Serial6      ALC   48   62   78   CKT_ALC_2  0       0       DOWN
Serial7      UTS   21   22   13   CKT_UTS    4830    4830    UP

Step 2 Verify that the peer between the router and the host is connected. Enter the show alps peer command and check the state field. OPENED indicates that the circuit is connected. DISCONN indicates that the circuit is disconnected.

router# show alps peers
local_peer : ip_address = 192.168.25.2
 
ip_address     conn_id             state    pkt_t  pkt_rx
-------------------------------------------------------------------------------------
192.168.20.3   MATIP_A_CKT_UTS     OPENED   1023   1023
192.168.70.2   MATIP_A_CKT_ALC_1   OPENED   4852   4757
192.168.70.2   MATIP_A_CKT_ALC_2   OPENED   1      1
192.168.70.3   MATIP_A_CKT_ALC_1   DISCONN  0      0
192.168.70.3   MATIP_A_CKT_ALC_2   DISCONN  0      0

Step 3 Verify that the ALPS circuit to the peer host is open and connected. Enter the show alps circuits command and check the state field. OPEN indicates that the circuit is connected. INOP indicates that the circuit is disconnected.

router# show alps circuits

name        pri_peer       curr_peer      dlc   state  pkt_tx  pkt_rx
-------------------------------------------------------------------------------------
ALC_EMTOX   192.168.45.2   192.168.45.2   ALC   OPEN   944     944
UTS_AX25    192.168.45.2   192.168.45.2   UTS   OPEN   425     425

Monitoring and Maintaining ALPS

To monitor the status of the ALPS Enhancements feature, use the following commands in EXEC mode:

Command	Purpose
Router# show alps ascu [interface] [id] [detail]	Displays the status of the ALPS ASCU.
Router# show alps circuits [peer ip address] [name name] [detail]	Displays the status of the ALPS circuits.
Router# show alps peers [ipaddress addr] [detail]	Displays the status of the ALPS remote peers.

Configuration Examples

This section provides the following configuration examples:

• ALPS with MATIP Configuration for ALC and UTS Example

• ALPS Configuration for ALC and AX.25 Example

• ALPS Configuration for UTS and EMTOX Example

ALPS with MATIP Configuration for ALC and UTS Example

Figure 3 shows a simple example of a router topology for the ALPS with MATIP feature. The configuration corresponding to this topology follows.

ALC/UTS Router Configuration

(config)# hostname alps-rcpe
(config)# alps local-peer 192.168.25.2
(config)# alps keepalive interval 45 retry 2
(config)# alps remote-peer 192.168.20.3 protocol matip-a dynamic status-interval 60
(config)# alps remote-peer 192.168.70.2 protocol matip-a dynamic 0 no-circuit 10
(config)# alps remote-peer 192.168.70.3 protocol matip-a dynamic 45
(config)# alps enable-alarms peer 192.168.70.2
(config)# alps enable-alarms ascu
! 
(config)# alps circuit CKT_ALC_1
(config-alps-circ)# alps primary-peer 192.168.70.2 backup-peer 192.168.70.3
(config-alps-circ)# alps connection-type permanent
(config-alps-circ)# alps local-hld 2525
(config-alps-circ)# alps enable-circuit
!
(config)# alps circuit CKT_UTS
(config-alps-circ)# alps primary-peer 192.168.20.3
(config-alps-circ)# alps mpx single
(config-alps-circ)# alps idle-timer 90
(config-alps-circ)# alps local-hld 2527
(config-alps-circ)# alps enable-circuit
(config-alps-circ)# alps service-msg-interval 2
!
(config)# interface Loopback0
(config-if)# ip address 192.168.25.2 255.255.255.0
 
(config)# interface Serial0
(config-if)# ip address 210.100.50.2 255.255.255.0
(config-if)# encapsulation frame-relay IETF
(config-if)# frame-relay map ip 210.100.60.2 40
(config-if)# frame-relay map ip 210.100.70.2 50
 
!
 
(config)# interface Serial6
(config-if)# encapsulation alc
(config-if)# alps t1 6
(config-if)# alps t2 8
(config-if)# alps poll-pause 100
!
(config-if)# alps ascu 42
(config-alps-ascu)# alps default-circuit CKT_ALC_1
(config-alps-ascu)# alps a1-map 60 a2-map 70
(config-alps-ascu)# alps enable-ascu
!
(config-if)# alps ascu 45
(config-alps-ascu)# alps default-circuit CKT_ALC_1
(config-alps-ascu)# alps a1-map 60 a2-map 72
(config-alps-ascu)# alps enable-ascu
!
(config)# interface Serial7
(config-if)# encapsulation uts
(config-if)# alps n3 4
(config-if)# alps poll-pause 125
(config-if)# clock rate 4800
!
(config-if)# alps ascu 21
(config-alps-ascu)# alps default-circuit CKT_UTS
(config-alps-ascu)# alps a1-map 22 a2-map 13
(config-alps-ascu)# alps enable-ascu
!

ALPS Configuration for ALC and AX.25 Example

Figure 4 shows a simple router topology for the ALPS Enhancements feature with ALC encapsulation. The configuration for this topology follows.

(config)# alps local-peer 172.22.0.90
(config)# alps keepalive interval 60
(config)# alps remote-peer 172.22.0.91 
(config)# alps remote-peer 172.22.0.92 dynamic 60
(config)# alps service-msg-list 1 number 2 TERMINAL OFF
!
(config)# alps circuit CKT1
(config-alps-circ)# alps primary-peer 172.22.0.91 backup-peer 172.22.0.92
(config-alps-circ)# alps local-hld 4B09 remote-hld 5C00
(config-alps-circ)# alps connection-type permanent 30
(config-alps-circ)# alps lifetime-timer 3
(config-alps-circ)# alps hostlink 3 ax25 120 winout 3 winin 3
(config-alps-circ)# alps service-msg-interval 3
(config-alps-circ)# alps service-msg-list 1
(config-alps-circ)# alps enable-circuit
!
(config)# alps circuit CKT2
(config-alps-circ)# alps primary-peer 172.22.0.91 backup-peer 172.22.0.92
(config-alps-circ)# alps local-hld 4C01 remote-hld 5C00
(config-alps-circ)# alps hostlink 3 ax25 1500 winout 4 winin 5
(config-alps-circ)# alps enable-circuit
!
(config)# alps circuit CKT3
(config-alps-circ)# alps primary-peer 172.22.0.91
(config-alps-circ)# alps local-hld 4B10 remote-hld 5C00
(config-alps-circ)# alps connection-type permanent 30
(config-alps-circ)# alps lifetime-timer 6
(config-alps-circ)# alps hostlink 3 ax25 905 
(config-alps-circ)# alps enable-circuit
!
(config)# interface serial 1
(config-if)# ip address 172.22.0.90 255.255.255.0
!
(config)# interface serial 2
(config-if)# encapsulation alc
(config-if)# alps t1 3
(config-if)# alps t2 6
(config-if)# alps n1 3
(config-if)# alps n2 2
(config-if)# alps servlim 20
!
(config-if)# alps ascu 51
(config-alps-ascu)# alps default-circuit CKT1
(config-alps-ascu)# alps a1-map 40 a2-map 2D
(config-alps-ascu)# alps retry-option resend
(config-alps-ascu)# alps max-msg-length 1950
(config-alps-ascu)# alps error-display 6d 78
(config-alps-ascu)# alps enable-ascu
!
(config-if)# alps ascu 44
(config-alps-ascu)# alps default-circuit CKT1
(config-alps-ascu)# alps a1-map 40 a2-map 2E
(config-alps-ascu)# alps max-msg-length 590
(config-alps-ascu)# alps error-display 6d 78
(config-alps-ascu)# alps enable-ascu
!
(config-if)# alps ascu 7E
(config-alps-ascu)# alps default-circuit CKT2
(config-alps-ascu)# alps a1-map 40 a2-map 2F
(config-alps-ascu)# alps retry-option re-send
(config-alps-ascu)# alps max-msg-length 2000
(config-alps-ascu)# alps error-display 6d 78
(config-alps-ascu)# alps enable-ascu
 
(config)# interface serial 3
(config-if)# encapsulation alc
(config-if)# alps t1 5
(config-if)# alps t2 6
(config-if)# alps n1 1
(config-if)# alps n2 2
(config-if)# alps servlim 20
!
(config-if)# alps ascu 4B
(config-alps-ascu)# alps default-circuit CKT3
(config-alps-ascu)# alps a1-map 63 a2-map 41
(config-alps-ascu)# alps retry-option re-send
(config-alps-ascu)# alps max-msg-length 1960
(config-alps-ascu)# alps error-display 6d 78
(config-alps-ascu)# alps enable-ascu
 
(config-if)# alps ascu 66 
(config-alps-ascu)# alps default-circuit CKT2 
(config-alps-ascu)# alps a1-map 71 a2-map 21
(config-alps-ascu)# alps max-msg-length 3800
(config-alps-ascu)# alps error-display 6d 78
(config-alps-ascu)# alps enable-ascu

(config)# alps local-peer 172.22.0.91 promiscuous
(config)# interface serial 0
(config-if)# encapsulation x25 ax25
(config-if)# x25 ltc 1024
(config-if)# alps host-hld 5C00 host-link 3 ax25

(config)# alps local-peer 172.22.0.92 promiscuous
(config)# interface serial 0
(config-if)# encapsulation x25 ax25
(config-if)# x25 ltc 1024
(config-if)# alps host-hld 5C00 host-link 3 ax25

ALPS Configuration for UTS and EMTOX Example

The following configuration is an example of routing P1024C UTS data frames across the network between central and remote equipment:

Remote Router Configuration

(config)# hostname alps-rcpe
(config)# alps local-peer 200.100.25.2
(config)# alps keepalive interval 45 retry 5
(config)# alps remote-peer 200.100.40.2
(config)# alps enable-alarms peer 200.100.40.2
(config)# alps enable-alarms ascu
 
(config)# alps circuit UTS_EMTOX
(config-alps-circ)# alps primary-peer 200.100.40.2
(config-alps-circ)# alps idle-timer 90
(config-alps-circ)# alps local-hld 2525 remote-hld 5050
(config-alps-circ)# alps mpx single
(config-alps-circ)# alps hostlink 6 emtox 1100 ops 512 ips 512
(config-alps-circ)# alps service-msg-interval 2
(config-alps-circ)# alps enable-circuit
 
(config)# interface Loopback0
(config-if)# ip address 200.100.25.2 255.255.255.0
 
(config)# interface Serial0
(config-if)# ip address 200.100.50.2 255.255.255.0
(config-if)# encapsulation frame-relay IETF
(config-if)# frame-relay map ip 200.100.50.3 20
 
(config)# interface Serial1
(config-if)# encapsulation uts
(config-if)# alps n1 5
(config-if)# alps n3 4
(config-if)# alps poll-pause 200
(config-if)# clock rate 4800
!
(config-if)# alps ascu 21
(config-alps-ascu)# alps default-circuit UTS_EMTOX
(config-alps-ascu)# alps a1-map 22 a2-map 13
(config-alps-ascu)# alps enable-ascu
!

Central CPE Configuration

(config)# hostname alps-ccpe
(config)# alps local-peer 200.100.40.2 promiscuous
(config)# alps enable-alarms circuit
!
(config)# interface Loopback0
(config-if)# ip address 200.100.40.2 255.255.255.0
!
(config)# interface Serial0
(config-if)# ip address 200.100.50.3 255.255.255.0
(config-if)# encapsulation frame-relay IETF
(config-if)# clock rate 56000
(config-if)# frame-relay map ip 200.100.50.2 20
!
(config)# interface Serial2
(config-if)# encapsulation x25 dce
(config-if)# alps host-hld 5050 host-link 6 emtox 2222
(config-if)# alps translate 110* 200.100.25.2
(config-if)# clock rate 64000

Command Reference

This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.1 command reference publications.

• alps ascu

• alps auto-reset

• alps service-msg-list number

• alps service-msg data-drop

• alps service-msg format

• alps service-msg status-change

• alps t1

• show alps ascu

alps ascu

To specify a physical ASCU identity, use the alps ascu interface configuration command. To remove the ASCU from the interface and delete any messages queued for transmission to the ASCU or the network, use the no form of this command.

alps ascu 4B

alps auto-reset

To automatically reset a non-responsive ALC ASCU in the DOWN state, use the alps auto-reset ALPS ASCU submode command. To disable the automatic reset, use the no form of this command.

alps auto-reset

alps service-msg-list number

To define the service message identity and its contents for a service message list, use the alps service-msg-list number global configuration command. To remove a service message number from the service message list configuration, use the no form of this command.

Table 2 shows the default service message text strings:

Table2: Service Message Default Text Strings

Message Number	Event	Text String
1	ALPS circuit to host is opened.	CONNECTION UP
2	X.25 virtual circuit at the host is cleared.	DISC BY THE HOST
3	X.25 interface at the host is down.	HOST ISOLATED
4	No response from the host router when trying to establish a connection.	NETWORK PROBLEM
5	Connection to host was disconnected because of inactivity.	READY TO CONNECT
6	Network is congested.	CONGESTION
7	Network congestion has cleared.	PLEASE PROCEED
8	Network operator has disabled the path to the host.	DISC BY NET OPERAT

alps service-msg-list 1 number 2 "Turn off the terminal NOW."
 

alps service-msg-list 1 number 3 $OFF$

alps service-msg data-drop

To specify where to retrieve the terminal address to be used when a service message is sent to an ASCU as a result of a dropped data message from a terminal, use the alps service-msg data-drop interface configuration command. To remove the terminal address specification, use the no form of this command.

alps service-msg data-drop msg-term

alps service-msg format

To specify the protocol format of service messages sent from the router to an ASCU, use the alps service-msg format interface configuration command. To remove the protocol format specification, use the no form of this command.

alps service-msg format apollo

alps service-msg status-change

To specify that ALPS circuit status change service messages be sent to ASCUs on the serial interface, use the alps service-msg status-change interface configuration command. To send service messages for ALPS circuit status changes only when ALC data messages are dropped, use the no form of this command.

alps service-msg status-change

alps t1

To specify the timeout delay between polling and response, use the alps t1 interface configuration command. To reassert the default poll timeout value of 0.5 seconds, use the no form of this command.

alps t1 5

show alps ascu

To display the status of the ALPS ASCU, use the show alps ascu EXEC command.

router# show alps ascu
interface  dlc id a1 a2 circuit        pkt_tx      pkt_rx      state 
---------------------------------------------------------------------
Serial3    ALC 41 41 41 CKT-1          0           0           UP    
Serial3    ALC 42 41 42 CKT-1          0           0           UP    
Serial3    ALC 45 41 45 CKT-1          29          1484        UP    
 

router# show alps ascu detail
ascu 41 on i/f Serial2, dlc = ALC, state = UP
  default-circuit = CKT1, a1 = 22, a2 = 4A
  max_msg_len = 962 retry_option = none
  err_disp_terminal = 114, err_disp_line = 102
  pkt_tx = 0, byte_tx = 0, pkt_rx = 0, byte_rx = 0
  bad_CCC = 0, garbledMsgs = 0, T1Timeouts = 0
 

Table 3 describes significant fields in the display:

Table3: show alps ascu Field Descriptions

Field	Description
dlc	Data link control.
state	Status of connection; UP, DOWN or DISABLED.
default-circuit	Name of the default circuit.
a1	Logical ASCU identification information for A1.
a2	Logical ASCU identification information for A2.
max_msg_len	Maximum input message length. Protocol level count that includes all protocol overhead plus data. The valid range is 1 to 3840 bytes. The default is 962. Anything over the maximum is discarded and the interface giant counter is incremented. This does not apply to the GarbledMsg for the ASCU.
retry_option	Retry option. When a message with a bad cycle check character (CCC) is received from an ASCU, a retry option can be configured using the alps retry-option command. The retry option configures the customer premise equipment (CPE) to transmit a message to the ASCU. The following retry options are available: resend---Indicator LED signals the operator at the ASCU to resend data. reenter---Service messages signal the operator at the ASCU to reenter data. The default retry option is no retry.
err_disp_terminal	Terminal address where error service messages are sent.
err_disp_line	Screen line number where error service messages are sent.
pkt_tx	Packets transmitted.
byte_tx	Bytes transmitted.
pkt_rx	Packets received.
byte_rx	Bytes received.
bad_CCC	Number of bad CCCs. A bad_CCC occurs when the proper control characters were received, the characters did not exceed the maximum length, and the CCC calculation fails.
garbledMsgs	Number of garbled messages. Garbled messages are a result of a range of different errors, including the following: an unexpected character is received the maximum interface buffer size is exceeded the maximum message length is exceeded
T1Timeouts	Number of response timeouts.

Debug Commands

This section documents modified debug commands. All other commands used with this feature are documented in the Cisco IOS Release 12.1command reference publications.

• debug alps ascu

• debug alps snmp

debug alps ascu

To enable debugging for ALPS ASCUs, use the debug alps ascu privileged EXEC command. To disable debugging, use the no form of this command.

debug alps ascu {event | packet | detail | all | format {ipars | router | both}} [interface [ascu id]]

no debug alps ascu {event | packet | detail | all | format {ipars | router | both}} [interface [ascu id]]

Syntax Description

event	Displays ASCU events or protocol errors.
packet	Displays transmitted or received packets.
detail	Displays all ASCU protocol events.
all	Enables event, packet, and detail debugging.
format {ipars | router | both}	Specifies how to display ASCU addresses and the hexadecimal data in the debug output: ipars---Displays the IPARS hexadecimal output, only. router---Displays the router hexadecimal output, only. both---Displays both the IPARS and router hexadecimal output. The only difference between the IPARS output and the router output is the format of the hexadecimal data.
interface	(Optional) Enables debugging on a specified interface. applies only to the event, packet, detail, and all keywords.
ascu id	(Optional) Enables debugging for a specified ASCU.

Defaults

Debugging is off.

Command History

Release	Modification
11.3(6)T	This command was introduced for limited availability.
12.0(1)	This command was available for general release.
12.0(5)T	This command was modified.
12.1(2)T	The format, ipars, router, and both keywords were added. The output for this command was modified to include IPARS and router formats.

Usage Guidelines

To enable debugging for a group of ASCUs enter a separate command for each ASCU interface and IA combination.

The interface option applies only to the event, packet, detail, and all keywords.

---

NoteTo specify the particular debug tracing level (event, packet, detail or all) and the format (router, ipars or both), you must configure the debug alps ascu command two times; once to configure the debug tracing level and once to configure the format.

---

---

NoteTo log messages to an internal buffer, use the logging buffered global configuration command. To display the state of logging (syslog), use the show logging privileged EXEC command. For information on these commands and other commands used to customize logs, refer to the Cisco IOS Release 12.1 Configuration Fundamentals Configuration Guide and Cisco IOS Release 12.1 Configuration Fundamentals Command Reference.

---

Examples

The following output is from the debug alps ascu event command, showing events or protocol errors in router format for ASCU 42 on interface Serial7:

router# debug alps ascu format router
router# debug alps ascu event Serial7 42
ALPS ASCU: T1 expired for ascu 42 on i/f Serial7
ALPS ASCU: DOWN event while UP for ascu 42 on i/f Serial7 : C1 count = 1
 

---

NoteIf you specify the ipars or both format for the event or detail tracing level, both the IPARS and router formats will be displayed.

---

The following output is from the debug alps ascu event command, showing events or protocol errors in ipars format for ASCU 42 on interface Serial7:

router# debug alps ascu format ipars
router# debug alps ascu event Serial7 42
ALPS ASCU: T1 expired for ascu 42/2F on i/f Serial7
ALPS ASCU: DOWN event while UP for ascu 42/2F on i/f Serial7 : C1 count = 1
 

The following output is from the debug alps ascu detail command, showing all protocol events in router format for ASCU 42 on interface Serial6:

router# debug alps ascu format router
router# debug alps ascu detail Serial6 42
ALPS ASCU: Tx ALC POLL MSG (+ 0 pad bytes) to ascu 42 on i/f Serial6
ALPS ASCU: ALC GO AHD MSG rcvd from ascu 42 on i/f Serial6
ALPS ASCU: Tx ALC POLL MSG (+ 0 pad bytes) to ascu 42 on i/f Serial6
ALPS ASCU: ALC GO AHD MSG rcvd from ascu 42 on i/f Serial6
ALPS ASCU: Tx ALC POLL MSG (+ 0 pad bytes) to ascu 42 on i/f Serial6
ALPS ASCU: Rx ALC DATA MSG (14 bytes + CCC) from ascu 42 on i/f Serial6, fwd to ckt
RTP_MATIP
ALPS ASCU: ALC GO AHD MSG rcvd from ascu 42 on i/f Serial6
ALPS ASCU: Tx ALC DATA MSG (14 bytes + CCC + 0 pad bytes) to ascu 42 on i/f Serial6
ALPS ASCU: Tx ALC POLL MSG (3 bytes + CCC + 0 pad bytes) to ascu 42 on i/f Serial6
 

---

NoteIf you specify the ipars or both format for the event or detail tracing level, both the IPARS and router formats will be displayed.

---

The following output is from the debug alps ascu detail command, showing all protocol events in both format for ASCU 42 on interface Serial6:

router# debug alps ascu format both
router# debug alps ascu detail Serial6 42
ALPS ASCU: Tx ALC POLL MSG (+ 0 pad bytes) to ascu 42/2F on i/f Serial6
ALPS ASCU: ALC GO AHD MSG rcvd from ascu 42/2F on i/f Serial6
ALPS ASCU: Tx ALC POLL MSG (+ 0 pad bytes) to ascu 42/2F on i/f Serial6
ALPS ASCU: ALC GO AHD MSG rcvd from ascu 42/2F on i/f Serial6
ALPS ASCU: Tx ALC POLL MSG (+ 0 pad bytes) to ascu 42/2F on i/f Serial6
ALPS ASCU: Rx ALC DATA MSG (14 bytes + CCC) from ascu 42/2F on i/f Serial6, fwd to ckt
RTP_MATIP
ALPS ASCU: ALC GO AHD MSG rcvd from ascu 42/2F on i/f Serial6
ALPS ASCU: Tx ALC DATA MSG (14 bytes + CCC + 0 pad bytes) to ascu 42/2F on i/f Serial6
ALPS ASCU: Tx ALC POLL MSG (3 bytes + CCC + 0 pad bytes) to ascu 42/2F on i/f Serial6
 

The following output is from the debug alps ascu packet command, showing all packets transmitted or received in router format for ASCU 42 on interface Serial6:

router# debug alps ascu packet Serial6 42
ALPS ASCU: Tx ALC SERVICE MSG (18 bytes + CCC + 0 pad bytes) to ascu 42 on i/f Serial6
02321D26 0C261616          
140C0D18 26163135 0611C6                  
ALPS ASCU: Rx ALC DATA MSG (14 bytes + CCC) from ascu 42 on i/f Serial6, fwd ckt
RTP_MATIP
42607866 65717866          
65717966 755124                               
ALPS ASCU: Tx ALC DATA MSG (14 bytes + CCC + 0 pad bytes) to ascu 42 on i/f Serial6
022038 26253138           
26253139 263511E4
 

The following output is from the debug alps ascu packet command, showing all packets transmitted or received in ipars format for ASCU 42 on interface Serial6:

router# debug alps ascu packet Serial6 42
ALPS ASCU: Tx ALC SERVICE MSG (18 bytes + CCC + 0 pad bytes) to ascu 42/2F on i/f Serial6
ALPS IPARS Format: 
2F2C1126 33262525 
35331339 26251C14 271DC6
ALPS ASCU: Rx ALC DATA MSG (14 bytes + CCC) from ascu 42/2F on i/f Serial6, fwd ckt
RTP_MATIP
ALPS IPARS Format: 
2F3E3826 161C3826
161C1826 141D24
ALPS ASCU: Tx ALC DATA MSG (14 bytes + CCC + 0 pad bytes) to ascu 42/2F on i/f Serial6
ALPS IPARS Format: 
2F3E38 26161C38
26161C18 26141DE4
 

The following output is from the debug alps ascu packet command, showing all packets transmitted or received in both format for ASCU 42 on interface Serial6:

router# debug alps ascu packet Serial6 42
ALPS ASCU: Tx ALC SERVICE MSG (18 bytes + CCC + 0 pad bytes) to ascu 42/2F on i/f Serial6
ALPS Router Format:
02321D26 0C261616          
140C0D18 26163135 0611C6 
ALPS IPARS Format: 
2F2C1126 33262525 
35331339 26251C14 271DC6
ALPS ASCU: Rx ALC DATA MSG (14 bytes + CCC) from ascu 42/2F on i/f Serial6, fwd ckt
RTP_MATIP
ALPS Router Format:
42607866 65717866
65717966 755124
ALPS IPARS Format: 
2F3E3826 161C3826
161C1826 141D24
ALPS ASCU: Tx ALC DATA MSG (14 bytes + CCC + 0 pad bytes) to ascu 42/2F on i/f Serial6
ALPS Router Format:
022038 26253138           
26253139 263511E4
ALPS IPARS Format: 
2F3E38 26161C38
26161C18 26141DE4

debug alps snmp

Use the debug alps snmp privileged EXEC command to enable debugging for ALPS SNMP agents. To disable debugging, use the no form of this command.

ALPS CktStatusChange Notification for circuit CKT-1
ALPS AscuStatusChange Notification for ascu (Serial3, 41)
PeerConnStatusChange Notification for peer (10.227.50.106, MATIP_A_CKT-1)
 

ALPS CktOpenFailure Notification for circuit CKT1
 

ALPS CktPartialReject Notification for ascu (Serial2, 41) on circuit CKT1

Glossary

agent set control unit---See ASCU.

Airline Control Protocol---See ALC.

Airline Product Set---See ALPS.

airline protocol---A generic term that refers to the airline reservation system data and the protocols such as P1024B (ALC), P1024C (UTS), and MATIP that are used to transport the data between the mainframe and the ASCUs.

Airline X.25---See AX.25.

ALC---Airline Control Protocol. P1024B, a data link layer polled protocol that runs in full-duplex mode over synchronous serial (V.24) lines and uses the binary-coded decimal (BCD) character set.

ALPS---Cisco's Airline Product Set feature. The feature includes all the components involved in transporting airline protocol data across a TCP/IP based network to mainframe reservation systems.

ALPS circuit---Communication path across a TCP connection between a host reservation system and an ASCU. When MATIP encapsulation is used on an ALPS circuit, it is equivalent to a MATIP session.

ALPS Tunneling Protocol---See ATP.

ASCU---Agent set control unit. An airline reservations system terminal controller.

ASCU interchange address---See IA.

ATP---ALPS Tunneling Protocol. A protocol used to transport ALPS data across a TCP/IP network between an ALC/UTS router and an AX.25/EMTOX router. It consists of a set of messages (or primitives) to activate and deactivate ALPS ATP circuits and pass data.

AX.25---Airline X.25. This is an X.25 implementation based on CCITT 1984 recommendation using permanent virtual circuits (PVCs) only. There is one non-standard aspect of this protocol, packets may be sent with the m-bit set, but the size of the packet is less than the maximum packet size for the virtual circuit.

EMTOX---Exchange of Mixed Traffic over X.25. This is a specification for transmitting airline protocol data over standard X.25 switched virtual circuits (SVCs).

Exchange of Mixed Traffic over X.25---See EMTOX.

high-level designator---See HLD.

HLD---high-level designator. Designator that logically identifies the peer session endpoints used if the multiplex in the circuit is set to group. To specify the multiplexing and the ASCU identification header for the circuit, use the alps mpx command.

IA---ASCU interchange address. Specifies a physical ASCU identity.

IATA---International Airline Transport Association.

International Airline Transport Association---See IATA.

Local switching---The ability for customer premise equipment (CPE) to forward traffic between an ASCU and an AX.25/EMTOX host which are both attached to the same CPE.

Management Information Base---See MIB.

Mapping of Airline Traffic over Internet Protocol---See MATIP.

MATIP---Mapping of Airline Traffic over Internet Protocol. A standard defined in RFC 2351 for transporting airline reservation, ticketing, and messaging traffic over TCP/IP.

messaging traffic---See Type B traffic.

MIB---Management Information Base. Database of network management information that is used and maintained by a network management protocol such as SNMP or CMIP. The value of a MIB object can be changed or retrieved using SNMP or Common Management Information Protocol (CMIP) commands, usually through a GUI network management system. MIB objects are organized in a tree structure that includes public (standard) and private (proprietary) branches.

remote router---Routers with the ALPS feature that are physically connected to the ASCUs.

Simple Network Management Protocol---See SNMP.

SNMP---Simple Network Management Protocol. Network management protocol used almost exclusively in TCP/IP networks. SNMP provides a means to monitor and control network devices, and to manage configurations, statistics collection, performance, and security.

transactional traffic---See Type A traffic.

Type A traffic---Transactional traffic. Typically, this is conversational traffic exchanged between a host and its ASCUs for terminal queries and responses for reservation systems. There is another form of typeA traffic called host-to-host traffic.

Type B traffic---Messaging traffic. Typically, this is e-mail application traffic in IATA-compliant format.

Universal Terminal Support---See UTS.

UTS---Universal Terminal Support. P1024C is a data link layer protocol that runs in full-duplex mode over synchronous serial (V.24) lines and uses the ASCII character set.

X.25---ITU-T standard that defines how connections between data terminal equipment (DTE) and data circuit-terminating equipment (DCE) are maintained for remote terminal access and computer communications in public data networks (PDNs). X.25 specifies Link Access Procedure (LAPB), a data link layer protocol, and packet level protocol (PLP), a network layer protocol. Frame Relay has superseded X.25 to some degree.

Posted: Wed May 24 16:29:05 PDT 2000
Copyright 1989 - 2000©Cisco Systems Inc.