Cisco IOS Release 12.0 Dial Solutions Command Reference
Protocol Translation & Virtual Async Device Commands

Table Of Contents

Protocol Translation and Virtual Asynchronous Device Commands

service pt-vty-logging

Syntax Description

Default

Command Mode

Usage Guidelines

Examples

Related Commands

show interfaces virtual-access

Syntax Description

Command Mode

Usage Guidelines

Sample Display

show translate

Syntax Description

Command Mode

Usage Guidelines

Sample Display

show users (virtual access interfaces)

Syntax Description

Command Mode

Usage Guidelines

Sample Display

translate lat

Syntax Description

Default

Command Mode

Usage Guidelines

Examples

Related Commands

translate lat (virtual access interfaces)

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

translate tcp

Syntax Description

Default

Command Mode

Usage Guidelines

Examples

Related Commands

translate tcp (virtual access interfaces)

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

translate x25

Syntax Description

Default

Command Mode

Usage Guidelines

Examples

Related Commands

translate x25 (virtual access interfaces)

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

vty-async

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

vty-async dynamic-routing

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

vty-async header-compression

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

vty-async ipx ppp-client loopback

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

vty-async keepalive

Syntax Description

Default

Command Mode

Usage Guidelines

Examples

Related Commands

vty-async mtu

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

vty-async ppp authentication

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

vty-async ppp use-tacacs

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

vty-async virtual-template

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands

x25 host

Syntax Description

Default

Command Mode

Usage Guidelines

Examples

Related Commands

x29 access-list

Syntax Description

Default

Command Mode

Usage Guidelines

Example

x29 profile

Syntax Description

Default

Command Mode

Usage Guidelines

Example

Related Commands


Protocol Translation and Virtual Asynchronous Device Commands


Protocol translation provides transparent translation between systems running different protocols. The Cisco IOS software supports two-way virtual terminal protocol translation between nodes running X.25, local-area transport (LAT), and Telnet.

This chapter describes the commands that you use to configure protocol translation.

For protocol translation configuration information and examples, see the chapter "Configuring Protocol Translation and Virtual Asynchronous Devices" in the Dial Solutions Configuration Guide.

service pt-vty-logging

To log the X.121 calling address, Call User Data (CUD), and the IP address assigned to a vty asynchronous connection, use the service pt-vty-logging global configuration command. Use the no form of this command to disable this function.

service pt-vty-logging
no service pt-vty-logging

Syntax Description

This command has no arguments or keywords.

Default

This feature is disabled.

Command Mode

Global configuration

Usage Guidelines

This command first appeared in Cisco IOS Release 11.2.

This command permits you to log the X.121 calling address, Call User Data (CUD), and the IP address assigned to a vty asynchronous connection and direct this information to the console, an internal buffer, or a UNIX syslog server, depending on the logging configuration command you use. This authentication information can be used to associate an incoming PAD vty-asynchronous connection with an IP address.


Note   By default, the Cisco IOS software displays all messages to the console terminal.


Examples

The following example enables you to log the X.121 calling address, Call User Data (CUD), and the IP address assigned to a vty asynchronous connection and save this information to a syslog server:

service pt-vty-logging

The following is sample output resulting from the service pt-vty-logging command:

01:24:31: PAD18: call from 00011890 on LCI 10 PID 1 0 0 0 CUD "xyz"

describes the fields shown in the output.

Table 93

Field
Description

01:24:31:

Time stamp.

PAD18:

Active vty line number using the PAD connection.

00011890

The source/calling address.

on LCI 10

Incoming call is initiated on Logical Channel 10.

PID 1 0 0 0

The PAD Protocol Identifier is "01000000."

CUD "xyz"

Call User Data "xyz." If no CUD is available, this field will appear as follows:

CUD ""

Service PT-Vty-Logging Field Descriptions

Related Commands

You can use the master indexes or search online to find documentation of related commands.

logging
logging buffered

show interfaces virtual-access

Use the show interfaces virtual-access EXEC command to display information about virtual access interfaces.

show interfaces virtual-access number

Syntax Description

number

Number of the virtual terminal (vty) line on which the virtual access interface has been created.


Command Mode

EXEC

Usage Guidelines

This command first appeared in Cisco IOS Release 11.3.

To identify the number of the vty line on which the virtual access interface was created, issue the show users EXEC command included in this feature chapter.

Sample Display

The following is sample output from the show interfaces virtual-access command:

router# show interface virtual-access 2

Virtual-Access2 is up, line protocol is up 
  Hardware is Virtual Access interface
  Interface is unnumbered. Using address of Ethernet0 (10.0.21.14)
  MTU 1500 bytes, BW 9 Kbit, DLY 100000 usec, rely 255/255, load 1/255
  Encapsulation PPP, loopback not set, keepalive not set
  DTR is pulsed for 0 seconds on reset
  LCP Open
  Open: IPCP
  Last input 00:00:06, output 00:00:05, output hang never
  Last clearing of "show interface" counters 00:14:58
  Input queue: 1/75/0 (size/max/drops); Total output drops: 0 
  Queueing strategy: weighted fair
  Output queue: 0/64/0 (size/threshold/drops) 
     Conversations  0/1 (active/max active)
     Reserved Conversations 0/0 (allocated/max allocated)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     4 packets input, 76 bytes, 0 no buffer
     Received 0 broadcasts, 0 runts, 0 giants
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     8 packets output, 330 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 output buffer failures, 0 output buffers swapped out
     0 carrier transitions

describes the fields shown in this sample display.

Table 94 Show Interfaces Virtual-Access Field Descriptions 

Field
Description

Virtual-Access ... is {up | down |
administratively down}

Indicates whether the interface is currently active (whether carrier detect is present), inactive, or has been taken down by an administrator.

line protocol is {up | down |
administratively down}

Indicates whether the software processes that handle the line protocol think the line is usable (that is, whether keepalives are successful).

Hardware is Virtual Access interface

Type of interface. In this case, the interface is a dynamically created virtual access interface existing on a vty line.

Internet address | interface is unnumbered

IP address, or IP unnumbered for the line. If unnumbered, the output lists the interface and IP address to which the line is assigned (Ethernet0 at 10.0.21.14 in this example).

MTU

Maximum transmission unit for packets on the virtual access interface.

BW

Bandwidth of the virtual access interface in kilobits per second.

DLY

Delay of the virtual access interface in microseconds.

rely

Reliability of the virtual access interface as a fraction of 255 (255/255 is 100% reliability), calculated as an exponential average over five minutes.

load

Load on the virtual access interface as a fraction of 255 (255/255 is completely saturated), calculated as an exponential average over five minutes. The calculation uses the value from the bandwidth interface configuration command.

Encapsulation

Encapsulation method assigned to the virtual access interface.

loopback

Test in which signals are sent and then directed back toward the source at some point along the communication path. Used to test network interface usability.

keepalive

Interval set for keepalive packets on the interface. If keepalives have not been enabled, the message is "keepalive not set."

DTR

Data Terminal Ready. An RS232-C circuit that is activated to let the DCE know when the DTE is ready to send and receive data.

LCP open | closed | req sent

Link control protocol (for PPP only; not for SLIP). LCP must come to the open state before any useful traffic can cross the link.

Open IPCP | IPXCP | ATCP

IPCP is IP control protocol for PPP, IPXCP is IPX control protocol for PPP, ATCP is AppleTalk control protocol for PPP. Network control protocols (NCPs) for the PPP suite. The NCP is negotiated after the LCP opens. The NCP must come into the open state before useful traffic can cross the link.

Last input

Number of hours, minutes, and seconds since the last packet was successfully received by a virtual access interface. Useful for knowing when a dead interface failed.

output

Number of hours, minutes, and seconds since the last packet was successfully transmitted by a virtual access interface.

output hang

Number of hours, minutes, and seconds (or never) since the virtual access interface was last reset because of a transmission that took too long. When the number of hours in any of the "last" fields exceeds 24 hours, the number of days and hours is printed. If that field overflows, asterisks are printed.

Last clearing

Time at which the counters that measure cumulative statistics (such as number of bytes transmitted and received) shown in this report were last reset to zero. Note that variables that might affect routing (for example, load and reliability) are not cleared when the counters are cleared.

*** indicates the elapsed time is too large to be displayed.
0:00:00 indicates the counters were cleared more than 231ms (and less than 232ms) ago.

Input queue, drops

Number of packets in input queues. Each number is followed by a slash, the maximum size of the queue, and the number of packets dropped due to a full queue.

Queueing strategy

Type of queueing selected to prioritize network traffic. The options are first-come-first-serve (FCFS) queueing, weighted fair queueing, priority queueing, and custom queueing.

Output queue

Number of packets in output queues. Each number is followed by a slash, the maximum size of the queue, and the number of packets dropped due to a full queue.

Conversations

Number of weighted fair queueing conversations.

Reserved Conversations

Number of reserved weighted fair queueing conversations. The example shows the number of allocated conversations divided by the number of maximum allocated conversations. In this case, there have been 0 reserved conversations.

Five minute input rate,
Five minute output rate

Average number of bits and packets transmitted per second in the last five minutes.

packets input

Total number of error-free packets received by the system.

bytes

Total number of bytes, including data and MAC encapsulation, in the error free packets received by the system.

no buffer

Number of received packets discarded because there was no buffer space in the main system. Compare with ignored count. Broadcast storms on Ethernets and bursts of noise on serial lines are often responsible for no input buffer events.

broadcasts

Total number of broadcast or multicast packets received by the virtual access interface.

runts

Number of packets that are discarded because they are smaller than the medium's minimum packet size.

giants

Number of packets that are discarded because they exceed the medium's maximum packet size.

input errors

Total number of no buffer, runts, giants, CRCs, frame, overrun, ignored, and abort counts. Other input-related errors can also increment the count, so that this sum might not balance with the other counts.

CRC

Cyclic redundancy checksum generated by the originating LAN station or far end device does not match the checksum calculated from data received. On a LAN, this often indicates noise or transmission problems on the LAN interface or the LAN bus. A high number of CRCs is usually the result of collisions or a station transmitting bad data. On a serial link, CRCs often indicate noise, gain hits or other transmission problems on the data link.

frame

Number of packets received incorrectly having a CRC error and a noninteger number of octets. On a serial line, this is usually the result of noise or other transmission problems.

overrun

Number of times the serial receiver hardware was unable to hand received data to a hardware buffer because the input rate exceeded the receiver's ability to handle the data.

ignored

Number of received packets ignored by the virtual access interface because the interface hardware ran low on internal buffers. These buffers are different than the system buffers mentioned previously in the buffer description. Broadcast storms and bursts of noise can cause the ignored count to be incremented.

abort

Illegal sequence of one bits on a virtual access interface. This usually indicates a clocking problem between the virtual access interface and the data link equipment.

packets output

Total number of messages transmitted by the system.

bytes

Total number of bytes, including data and MAC encapsulation, transmitted by the system.

underruns

Number of times that the far-end transmitter has been running faster than the near-end communication server's receiver can handle. This might never be reported on some virtual access interfaces.

output errors

Sum of all errors that prevented the final transmission of datagrams out of the virtual access interface being examined. Note that this might not balance with the sum of the enumerated output errors, as some datagrams might have more than one error, and others might have errors that do not fall into any of the tabulated categories.

collisions

Number of packets colliding.

interface resets

Number of times a virtual access interface has been completely reset. This can happen if packets queued for transmission were not sent within several seconds. This can be caused by a malfunctioning modem that is not supplying the transmit clock signal, or by a cable problem. If the system notices that the carrier detect line of a virtual access interface is up, but the line protocol is down, it periodically resets the interface in an effort to restart it. Interface resets can also occur when a virtual access interface is looped back or shut down.

restarts

Number of times the controller was restarted because of errors.

carrier transitions

Number of times the carrier detect (CD) signal of a virtual access interface has changed state. Indicates modem or line problems if the CD line changes state often. If data carrier detect (DCD) goes down and comes up, the carrier transition counter increments two times.

output buffer failures

Number of outgoing packets dropped from the output buffer.

output buffers swapped out

Number of times the output buffer was swapped out.


show translate

To view translation sessions that have been configured, use the show translate global configuration command:

show translate

Syntax Description

This command has no arguments or keywords.

Command Mode

Privileged EXEC

Usage Guidelines

This command first appeared in Cisco IOS Release 10.3.

The display from this command shows each translation session set up on the router. It shows the incoming device and virtual terminal protocol as well as the outgoing device and protocol.

Sample Display

The show translate output in this sample display is based on the following translation command configured:

translate x25 3131415912345 ppp ip-pool scope-name cardinal keepalive 0

If the previous translate command is enabled, the following output is created by the show translation command:


router# show translate 

Translate From: x25 3131415912345
          To:   PPP ip-pool scope-name cardinal keepalive 0
          1/1 users active, 1 peak, 1 total, 0 failures

describes fields shown in the display.

Table 95 Show Translate Field Descriptions 

Field
Description

Translate From: x25 3131415912345

Protocol (X.25) and address (3131415912345) of the incoming device.

To: PPP

The virtual terminal protocol (PPP).

ip-pool

Obtain an IP address from a DHCP proxy client or a local pool.

scope-name cardinal

Specific local scope name (cardinal) from which to obtain an IP address.

keepalive 0

Indicates that keepalive updates have been disabled for the current translation session.

1/1 users active

Number of users active over the total number of users.

1 peak

Maximum number of translate sessions up at any given time.

1 total

Total number of translation sessions.

0 failures

Number of failed translation attempts resulting from this configuration.


The show translate output in this sample display is based on the following translation command configured:

translate x25 31301234 PPP 192.168.14.23  ipx-client Loopback0 

If the previous translate command is enabled, the following output is created by the show translation command:


router# show translate 

Translate From: x25 31301234 
          To:   PPP 192.168.14.23  ipx-client Loopback0
          1/1 users active, 1 peak, 1 total, 0 failures

describes fields shown in the display.

Table 96 Show Translate Field Descriptions

Field
Description

Translate From: x25 31301234

Protocol (X.25) and address (31301234) of the incoming device.

To: PPP 192.168.14.23

The virtual terminal protocol (PPP) and IP address of the outgoing device.

ipx-client loopback0

Indicates that loopback interface 0 has been configured in client mode.

1/1 users active

Number of users active over the total number of users.

1 peak

Maximum number of translate sessions up at any given time.

1 total

Total number of translation sessions.

0 failures

Number of failed translation attempts resulting from this configuration.


show users (virtual access interfaces)

To display information about the active lines on the router, use the show users user EXEC command.

show users [all]

Syntax Description

all

(Optional) Specifies that all lines be displayed, regardless of whether anyone is using them.


Command Mode

User EXEC

Usage Guidelines

This command first appeared in Cisco IOS Release 11.2.

This command displays the line number, connection name, idle time, hosts (including virtual access interfaces) and terminal location.

Sample Display

The following is sample output from the show users command. You can use it to identify an active virtual access interface:

router> show users

Line         User      Host(s)                 Idle    Location
*  0 con 0             idle                    01:58
  10 vty 0             Virtual-Access2          0      1212321

The asterisk (*) indicates the current terminal session.

describes significant fields shown in the displays.

Table 97 Show Users Field Descriptions 

Field
Description

Line

Contains three subfields.

The first subfield (0, 10, and Vi2 in the sample output) is the absolute line number.

The second subfield (con and vty) indicates the type of line. Possible values follow:

con—Console

aux—Auxiliary port

TTY—Asynchronous terminal port

VTY—Virtual terminal

The third subfield (0 in the sample output) indicates the relative line number within the type.

User

User connected to the line. If no user is listed in this field, no one is using the line.

Host(s)

Host to which the user is connected (outgoing connection). A value of idle means that there is no outgoing connection to a host. The value of Virtual-Access2 in the example refers to virtual access interface number 2. The value of Virtual PPP (PT) is the virtual access interface referred to by the previous line.

Idle

Interval (in minutes) since the user has entered something.

Location

Either the hard-wired location for the line or, if there is an incoming connection, the host from which incoming connection originated. In the example, 1212321 refers to the X.121 address of an X.25 host.


translate lat

To translate a connection request to another protocol connection type when receiving a local-area transport (LAT) request, use the translate lat command in global configuration mode. To remove or change the translation request, use the no form of this command.

translate lat incoming-service-name [incoming-option] protocol outgoing-address [outgoing-options] [global-options]

no translate lat incoming-service-name [incoming-option] protocol outgoing-address [outgoing-options] [global-options]

Syntax Description

incoming-service-name

A LAT service name. When used on the incoming portion, service-name is the name of the service that users specify when trying to make a translated connection. This name can match the name of final destination resource, but this is not required. This can be useful when making remote translated connections.

incoming-option

(Optional) Incoming connection request option:

 

unadvertised—Prevents service advertisements from being broadcast to the network. This can be useful, for example, when you define translations for many printers, and you do not want these services advertised to other LAT terminal servers. (VMS systems will be able to connect to the service even though it is not advertised.)

protocol outgoing-address

A protocol name followed by an IP address or hostname. The hostname is translated to an IP address during configuration, unless you use the TCP host-name option, which allows load balancing by dynamically resolving an IP address from a hostname. These arguments can have the following values:

 

x25 X.121-address—X.25 and an X.121 address. The X.121 address must conform to specifications provided in the CCITT 1984 Red Book. This number generally consists of a portion that is administered by the PDN and a portion that is locally assigned. You must be sure that the numbers that you assign agree with the addresses assigned to you by the X.25 service provider. The X.121 addresses will generally be subaddresses of the X.121 address for the X.25 network interface. Typically, the interface address will be a 12-digit number. Any additional digits are interpreted as a subaddress. The PDN still routes these calls to the interface, and the Cisco IOS software itself is responsible for dealing with the extra digits appropriately.

 

tcp ip-address—TCP/IP Telnet and a standard IP address or hostname. The argument ip-address is a standard, four-part dotted decimal IP address or the name of an IP host that can be resolved by the Domain Name System (DNS) or explicit specification in an ip host command.

 

slip ip-address—The argument ip-address is a standard, four-part dotted decimal IP address or the name of an IP host that can be resolved by the Domain Name System (DNS).

 

ppp ip-address—The argument ip-address is a standard, four-part dotted decimal IP address or the name of an IP host that can be resolved by the Domain Name System (DNS).

 

autocommand—Enables you to specify a string for an outgoing connection. The string executes upon connection to a host. If you want to enable ARA on an outgoing connection, you need to specify autocommand arap.

The autocommand option is necessary for ARA, because ARA does not use addressing, and autocommand permits you to invoke the arap string.

If the string following autocommand has one or more spaces as part of the string, you must place quotation marks (" ") around the string. For example, if you specify autocommand tn3270 abracadabra, you must enclose tn3270 abracadabra in quotes.

The autocommand option applies only to outgoing connections.

You can issue any EXEC command and any switch or hostname as an argument to the autocommand option.

outgoing-options

(Optional) Incoming and outgoing connection request options. These arguments can have the following values:

 

X.25 translation options:

 

cud c-u-data—Sends the specified Call User Data (CUD) text (c-u-data) as part of an outgoing call request after the protocol identification bytes.

 

no-reverse—Specifies that outgoing calls are not to use reverse charging, when the interface default is that all outgoing calls are reverse charged.

 

profile profile—Sets the X.3 Packet Assembler/Disassembler (PAD) parameters as defined in the profile created by the x29 profile command.

 

pvc number {[interface serial number] [packetsize in-size out-size] [windowsize in-size out-size]}—The number argument specifies the virtual circuit channel number of the connection, which must be less than the virtual circuits assigned to the switched virtual circuit (SVC). Only one session is allowed per permanent virtual circuit (PVC). Use the following optional keywords to further define the connection:

interface serial number—Specifies a PVC interface on which to set up the PVC connection.

packetsize in-size out-size—Specifies the input packet size (in-size) and output packet size (out-size) for the PVC. Following are valid packet size values: 16, 32, 64, 128, 256, 512 1024, 2048, and 4096

windowsize in-size out-size—Specifies the packet count for input windows (in-size) and output windows (out-size) for the outgoing translation. Values of in-size and out-size range 1 to 127 and must not be greater than the value set for the x25 modulo command. You must specify the same value for in-size and out-size.

 

reverse—Provides reverse charging for X.25 on a per-call rather than a per-interface basis. Requests reverse charges on a specified X.121 address, even if the serial interface is not configured to request reverse charge calls. This is an outgoing option only.

 

use-map—Applies x25 map pad command entry options (such as CUD and idle) and facilities (such as packet in, packet out, win in, and win out) to the outgoing protocol translation call. This application occurs when the protocol translation function searches the X.25 map PAD entries and finds a matching X.121 destination address. The X.25 map facilities applied to the outgoing translation can be viewed with the show translation command throughout the duration of the translation session.

 

Telnet TCP translation option:

 

binary—Negotiates Telnet binary mode on the Telnet connection.

 

host-name—Stores the hostname rather than its IP address, thereby allowing the hostname to be resolved at connection time instead of configuration time. There is also a rotor keyword suboption that you can use to modify the behavior of the host-name keyword by allowing one of the IP addresses defined by the ip host configuration command to be chosen randomly. If one address fails, another one will be tried, and so on until all address choices are exhausted. You can use the rotor keyword, therefore, to provide basic load sharing of the IP destinations.

 

multibyte-IAC—Always treat multiple Interpret as Command (IAC) escape character codes as a Telnet command.

 

port number—For incoming connections, number of the port to match. The default is port 23 (any port). For outgoing connections, number of the port to use. The default is port 23 (Telnet).

 

source-interface address—Specifies the source address used for Telnet connections initiated by the router.

 

stream—Performs stream processing, which enables a raw TCP stream with no Telnet control sequences. A stream connection does not process or generate any Telnet options, and prevents Telnet processing of the data stream as well. This option might be useful for connections to ports running the UNIX-to-UNIX Connection Protocol (UUCP) or other non-Telnet protocols, or to ports connected to printers. For ports connected to printers using Telnet, the stream option prevents some of usual problems associated with using Telnet for printers, such as odd responses from carriage returns or line feeds and echoing of data back to VMS systems.

 

Serial Line IP (SLIP) translation options:

 

ip-pool—Obtain an IP address from a DHCP proxy client or a local pool. If the scope-name option is not specified, the address is obtained from a DHCP proxy client. If the scope-name option is specified, the IP address is obtained from the specified local pool.

 

scope-name—Specific local scope name from which to obtain an IP address. Can specify a range of IP addresses.

 

header-compression [passive]—Implements header compression on IP packets only. The passive keyword for SLIP connections permits compression on outgoing packets only if incoming TCP packets on the same virtual asynchronous interface are compressed. The default (without the passive option) permits compression on all traffic.

 

ipx loopback number—Permits clients running IPX-PPP over X.25 to connect through virtual terminal lines (vty) on the router. The loopback number option specifies the loopback interface to be created. A loopback interface must have been created and configured with a Novell IPX network number before IPX-PPP can work on the vty. The vty is assigned to the loopback interface.

 

keepalive number-of-seconds—Permits you to specify the interval at which keepalive packets are sent on SLIP and PPP virtual asynchronous interfaces. By default, keepalive packets are enabled and are sent every 10 seconds. To shut off keepalive packets, use a value of 0. The active keepalive interval is 1 through 32,767 seconds. When you do not change from the default of 10, the keepalive interval does not appear in more system:running-config or show translate command output.

 

mtu bytes—Permits you to change the maximum transmission unit (MTU) of packets that the virtual asynchronous interface supports. The default MTU is 1500 bytes on a virtual asynchronous interface. The acceptable range is 64 through 1,000,000 bytes.

 

routing—Permits routing updates between connections. This keyword is required if the destination device is not on a subnet connected to one of the interfaces on the router.

 

PPP translation options:

 

ip-pool—Obtain an IP address from a DHCP proxy client or a local pool. If the scope-name option is not specified, the address is obtained from a DHCP proxy client. If the scope-name option is specified, the IP address is obtained from the specified local pool.

 

scope-name—Specific local scope name from which to obtain an IP address. Can specify a range of IP addresses.

 

authentication {chap | pap}—Use CHAP or PAP authentication for PPP on virtual asynchronous interfaces. If you specify both options, order is significant; the system will try to use the first authentication type, then the second.

 

header-compression [passive]—Implements header compression on IP packets only. The option passive for SLIP connections permits compression on outgoing packets only if incoming TCP packets on the same virtual asynchronous interface are compressed. The default (without the passive option) permits compression on all traffic.

 

ipx loopback number—Permits clients running IPX-PPP over X.25 to connect through virtual terminal lines (vty) on the router. The loopback number option specifies the loopback interface to be created. A loopback interface must have been created and configured with a Novell IPX network number before IPX-PPP can work on the vty. The vty is assigned to the loopback interface.

 

keepalive number-of-seconds—Permits you to specify the interval at which keepalive packets are sent on SLIP and PPP virtual asynchronous interfaces. By default, keepalive packets are enabled and are sent every 10 seconds. To shut off keepalive packets, use a value of 0. The active keepalive interval is 1 through 32,767 seconds. When you do not change from the default of 10, the keepalive interval does not appear in more system:running-config or show translate output.

 

mtu bytes—Permits you to change the maximum transmission unit (MTU) of packets that the virtual asynchronous interface supports. The default MTU is 1500 bytes on a virtual asynchronous interface. The acceptable range is 64 through 1,000,000 bytes.

 

routing—Permits routing updates between connections. This option is required if the destination device is not on a subnet connected to one of the interfaces on the router.

 

use-tacacs—Enables TACACS authentication for CHAP or PAP on virtual asynchronous interfaces (for PPP only; TACACS authentication is not supported for SLIP).

global-options

(Optional) Translation options that can be used by any connection type. It can be one or more of the following:

 

access-class number—Allows the incoming call to be used by source hosts that match the access list parameters. The argument number is the number (integer) previously assigned to an access list. The standard access list is a number from 1 to 99.

 

local—Allows Telnet protocol negotiations to not be translated.

 

login—Requires that the user log in before the outgoing connection is made. This type of login is specified on the vty lines with the login command.

 

max-users number—Limits the number of simultaneous users of the translation to number (an integer you specify).

 

quiet—Suppresses printing of user-information messages.

 

rotor—Specifies a rotary among host-name addresses.


Default

No default translation parameters

Command Mode

Global configuration

Usage Guidelines

This command first appeared in Cisco IOS Release 10.0.

provides a visual aid for understanding how to use the translate lat command. In the table, follow the steps horizontally (from left to right). As you travel from step to step, you can choose from a vertical list of options at each step. As the table illustrates, you define the protocol translation connections by choosing a protocol keyword and supplying the appropriate address or service name. The protocol connection information is followed by optional features for that connection, as appropriate. The global options, in general, apply to all the connection types, but there are exceptions. See the examples for more explanations on how to enter this command.

Table 98 Translate LAT Command Options 

Incoming
Address

Step 1

Incoming Options

Step 2

Protocol Outgoing Address

Step 3

Outgoing
Options

Step 4

Global Options

Step 5

translate lat

incoming-service-name

unadvertised

x25 x.121-address

cud c-u-data

access-class number

       

no-reverse

local

       

profile profile

login

       

pvc [number | interface serial-number] packetsize in-size out-size windowsize in-size out-size

max-users number

       

reverse

quiet

       

use-map

rotor

     

tcp ip-address

binary

 
       

host-name name

 
       

multibyte-IAC

 
       

port

 
       

source-interface address

 
       

stream

 
     

slip ip-address

ip-pool [scope-name name]

 
       

header-compression [passive]

 
       

ipx loopback number

 
       

keepalive number-of-seconds

 
       

mtu bytes

 
       

routing

 
     

ppp ip-address

ip-pool [scope-name name]

 
       

authentication {pap | chap}

 
       

header-compression [passive]

 
       

ipx loopback number

 
       

keepalive number-of-seconds

 
       

mtu bytes

 
       

routing

 
       

use-tacacs

 
     

autocommand [arap | exec-string]


Examples

The following example illustrates incoming LAT to outgoing TCP translations. The unadvertised keyword prevents broadcast of service advertisements to other servers. Outgoing translated packets are transmitted to IP host rubble, TCP port 4005.

translate lat pt-printer1 unadvertised tcp rubble port 4005
          incoming        option        outgoing    option 

The following example translates LAT on an incoming line to SLIP on an outgoing line. It uses header compression only if incoming TCP packets on the same interface are compressed.

translate lat rudolph slip 10.0.0.4 header-compression 
          incoming    outgoing     option

The following example first shows the command to disable keepalive packets on a PPP line, then shows sample output from the show translate command when keepalive packets have been turned off on the line.

translate lat ramble ppp 172.21.2.2 keepalive 0
.
.
router# show translate 

Translate From: LAT ramble
          To:   PPP 172.21.2.2 keepalive 0 
          0/0 users active, 0 peak, 0 total, 0 failures

Related Commands

You can use the master indexes or search online to find documentation of related commands.

show translate
translate tcp
translate x25
x29 access-list
x29 profile

translate lat (virtual access interfaces)

When receiving a local-area transport (LAT) connection request to a service name, the Cisco router can automatically translate the request to another outgoing protocol connection type. To set this up, use the translate lat global configuration command.

The command syntax that follows shows how to apply a virtual interface template in place of outgoing translate options. If you are using virtual templates for protocol translation, all outgoing options are defined in the virtual interface template. lists all outgoing options and their corresponding interface configuration commands.

translate lat incoming-service-name [unadvertised] virtual-template number [global-options]

Syntax Description

incoming-service-name

A LAT service name. When used on the incoming portion of the translate lat command, service-name is the name of the service that users specify when trying to make a translated connection. This name can match the name of the final destination resource, but this match is not required. Such matches can be useful when making remote translated connections.

unadvertised

(Optional) The only incoming connection request option for LAT—Prevents service advertisements from being broadcast to the network. This can be useful, for example, when you define translations for many printers, and you do not want these services advertised to other LAT terminal servers. (VMS systems will be able to connect to the service even though it is not advertised.)

virtual-template number

Applies the virtual interface template specified by number in place of outgoing options.

global-options

(Optional) Translation options that can be used by any connection type. It can be one or more of the following:

 

access-class number—Allows the incoming call to be used by source hosts that match the access list parameters. The argument number is the number (integer) previously assigned to an access list. The standard access list is 1 to 99.

 

max-users number—Limits the number of simultaneous users of the translation to number (an integer you specify).

 

local—Allows Telnet protocol negotiations to not be translated.

 

rotor—Specifies a rotary among host-name addresses.

 

login—Requires that the user log in before the outgoing connection is made. This type of login is specified on the vty lines with the login command.

 

quiet—Suppresses printing of user-information messages.


Default

No default translation parameters

Command Mode

Global configuration

Usage Guidelines

This command first appeared before Cisco IOS Release 10.0.

You define the protocol translation connections by choosing a protocol keyword and supplying the appropriate address, hostname, or service name. The protocol connection information is followed by optional features for that connection, as appropriate. For example, the binary option is only appropriate with TCP/IP connections. The global options, in general, apply to all the connection types, but there are exceptions.

Rather than specifying outgoing translation options in the translate command, configure these options as interface configuration commands under the virtual interface template, then apply the virtual interface template to the translate command. maps outgoing translate command options to interface commands you can configure in the virtual interface template.

Table 99 Mapping Outgoing Translate Command Options to Interface Commands 

Translate Command Options
Corresponding Interface Configuration Command

ip-pool

peer default ip address {ip-address | dhcp | pool [poolname]}

header-compression

ip tcp header compression [on | off | passive]

routing

ip routing or ipx routing

mtu

mtu

keepalive

keepalive

authentication {chap | pap}

ppp authentication {chap | pap}

ppp use-tacacs

ppp use-tacacs

ipx loopback

ipx ppp-client loopback number


Example

The following example configures PPP tunneling from a PC across a LAT network. The remote PC is given the IP address 10.12.118.12 when it dials in. The unadvertised keyword prevents broadcast of service advertisements to other servers.

interface Virtual-Template1
 ip unnumbered Ethernet0
 peer default ip address 10.12.118.12
 ppp authentication chap
!
translate lat pt-printer1 unadvertised virtual-template 1 
          incoming         option         outgoing

Related Commands

You can use the master indexes or search online to find documentation of related commands.

show translate
translate tcp
translate x25
x29 access-list
x29 profile

translate tcp

To translate a TCP connection request to a particular destination address or hostname to another outgoing protocol connection type, use the translate tcp command in global configuration mode. To remove or change the translation request, use the no form of this command.

translate tcp incoming-address [incoming-options] protocol outgoing-address [outgoing-options] [global-options]

no translate tcp incoming-address [incoming-options