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Router Products Command Reference
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About This Manual
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Router Product Overview
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User Interface Commands
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System Image, Microcode Image, and Configuration File Load Comm
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Terminal Line and Modem Support Commands
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System Management Commands
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Interface Commands
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ATM Commands
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DDR Commands
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Frame Relay Commands
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ISDN Commands
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LAN Emulation Commands
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SMDS Commands
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X.25 Commands
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Apollo Domain Commands
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AppleTalk Commands
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Banyan VINES Commands
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DECnet Commands
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IP Commands
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IP Routing Protocols Commands
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ISO CLNS Commands
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Novell IPX Commands
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XNS Commands
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Source-Route Bridging Commands
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Remote Source-Route Bridging Commands
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DLSw+ Configuration Commands
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STUN and BSTUN Configuration Commands
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LLC2 and SDLC Configuration Commands
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IBM Network Media Translation Commands
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DSPU and SNA Service Point Configuration Commands
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SNA Frame Relay Access Support Commands
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APPN Configuration Commands
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IBM Channel Attach Configuration Commands
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References and Recommended Reading
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Ethernet Type Codes
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Regular Expressions
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ASCII character Set
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Platform Support
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Switching Appendix
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Table Of Contents
X.25 and LAPB Commands
Use the commands in this chapter to configure Link Access Procedure Balanced (LAPB), X.25, Defense Data Network (DDN) X.25, and Blacker Front End (BFE). X.25 provides remote terminal access; encapsulation for the IP, DECnet, XNS, ISO CLNS, AppleTalk, Novell IPX, Banyan VINES, and Apollo Domain protocols; and bridging.
X.25 virtual circuits can also be switched
•
Between interfaces—local routing)
•
•
To translate between X.25 and another protocol, refer to the Protocol Translation Configuration Guide and Command Reference publication.
For X.25 and LAPB configuration information and examples, refer to the "Configuring X.25 and LAPB" chapter in the Router Products Configuration Guide.
bfe
To allow the router to participate in emergency mode or to end participation in emergency mode when the interface is configured for x25 bfe-emergency decision and x25 bfe-decision ask, use the bfe EXEC command.
bfe {enter | leave} type number
Syntax Description
Command Mode
EXEC
Example
The following example enables an interface to participate in BFE emergency mode:
bfe enter serial 0Related Commands
encapsulation x25
x25 bfe-decision
x25 bfe-emergencyclear x25-vc
To clear switched virtual circuits (SVCs) and to reset permanent virtual circuits (PVCs), use the clear x25-vc privileged EXEC command. To clear all X.25 virtual circuits at once by restarting the packet layer service, use this command without an lcn argument.
clear x25-vc type number [lcn]
Syntax Description
Command Mode
Privileged EXEC
Example
The following example illustrates how to clear all virtual circuits on an interface:
clear x25-vc serial 1Related Command
cmns enable
To enable Connection-Mode Network Service (CMNS) on a nonserial interface, use the cmns enable interface configuration command. To disable this capability, use the no form of this command.
cmns enable
no cmns enableSyntax Description
This command has no arguments or keywords.
Default
The CMNS protocol is implicitly enabled whenever an X.25 encapsulation command is included with a serial interface configuration. A particular nonserial interface, however, must be explicitly configured to use CMNS.
Command Mode
Interface configuration
Usage Guidelines
After processing this command on the LAN interfaces (Ethernet, FDDI, and Token Ring), all the X.25-related interface configuration commands are made available.
Example
The following example enables CMNS on interface Ethernet 0:
interface ethernet 0cmns enableRelated Command
encapsulation lapb
To exchange datagrams over a serial interface using LAPB encapsulation, use the encapsulation lapb interface configuration command.
encapsulation lapb [dte | dce] [multi | protocol]
Syntax Description
Defaults
The default serial encapsulation is HDLC. You must explicitly configure a LAPB encapsulation method.
DTE operation is the default LAPB mode. IP is the default protocol.
Command Mode
Interface configuration
Usage Guidelines
LAPB encapsulations are appropriate only for private connections, where you have complete control over both ends of the link. Connections to X.25 networks should use an x25 encapsulation configuration, which operates the X.25 Layer 3 protocol above a LAPB Layer 2.
One end of the link must be a logical DCE and the other end a logical DTE. (This assignment is independent of the interface's hardware DTE/DCE identity.)
Both ends of the LAPB link must specify the same protocol encapsulation.
LAPB encapsulation is supported on serial lines configured for dial-on-demand (DDR) routing. It can be configured on DDR synchronous serial and ISDN interfaces and on DDR dialer rotary groups. It is not supported on asynchronous dialer interfaces.
A single-protocol LAPB encapsulation exchanges datagrams of the given protocol, each in a separate LAPB information frame. You should configure the interface with the protocol-specific parameters needed (for example, a link that carries IP traffic will have an IP address defined for the interface).
A multiprotocol LAPB encapsulation can exchange any or all of the protocols allowed for an serial interface. It also exchanges datagrams, each in a separate LAPB information frame. Since two bytes of protocol identification data precede the protocol data, you do not need to configure the interface with all of the protocol-specific parameters needed for each protocol carried.
Beginning with Cisco IOS Release 11.0, multiprotocol LAPB encapsulation supports transparent bridging. This feature requires use of the encapsulation lapb multi command followed by the bridge-group command, which identifies the bridge group associated with multiprotocol LAPB encapsulation. This feature does not support use of the encapsulation lapb protocol command with a bridge keyword.
Beginning with Release 10.3, LAPB encapsulation supports the priority and custom queueing features.
Example
The following example sets the operating mode as DTE and specifies that AppleTalk protocol traffic will be carried on the LAPB line:
interface serial 1encapsulation lapb dte appletalkRelated Command
A dagger (†) indicates that the command is documented in another chapter.
bridge-group†
encapsulation x25
To specify an serial interface's operation as an X.25 device, use the encapsulation x25 interface configuration command.
encapsulation x25 [dte | dce] [ddn | bfe] | [ietf]
Syntax Description
Defaults
The default serial encapsulation is HDLC. You must explicitly configure an X.25 encapsulation method.
DTE operation is the default X.25 mode. Cisco's traditional X.25 encapsulation method is the default.
Command Mode
Interface configuration
Usage Guidelines
One end of an X.25 link must be a logical DCE and the other end a logical DTE. (This assignment is independent of the interface's hardware DTE/DCE identity.) Typically, when connecting to a public data network (PDN), the customer equipment acts as the DTE and the PDN attachment acts as the DCE.
Cisco has supported the encapsulation of a number of datagram protocols for quite some time, using a standard means when available and proprietary means when necessary. More recently the IETF adopted a standard, RFC 1356, for encapsulating most types of datagram traffic over X.25. X.25 interfaces use Cisco's traditional method unless explicitly configured for IETF operation; if the ietf keyword is specified, that standard will be used unless Cisco's traditional method is explicitly configured. For details see the x25 map command.
When an X.25 interface is reconfigured, all of the interface's X.25 parameters are initialized except the x25 map commands. The x25 map statements that are configured for an interface are not deleted when the encapsulation is changed, so they will be retained if the interface is later reconfigured for X.25 operation.
A router attaching to the Defense Data Network (DDN) or to a Blacker Front End (BFE) device can be configured to use their respective algorithms to convert between IP and X.121 addresses by using the ddn or bfe options, respectively. An IP address should be assigned to the interface, from which the algorithm will generate the interface's X.121 address; for proper operation, this X.121 address should not be modified.
A router DDN attachment can operate as either a DTE or a DCE device. A BFE attachment can operate only as a DTE device. The ietf option is not available if either the ddn or bfe option is selected.
Example
The following example configures the interface for connection to a Blacker Front End device:
interface serial 0encapsulation x25 bfelapb interface-outage
To specify a period during which a link will remain connected, even if a brief hardware outage occurs, use the lapb interface-outage interface configuration command.
lapb interface-outage milliseconds
Syntax Description
milliseconds
Number of milliseconds a hardware outage can last without having the protocol disconnect the service. The default is 0 milliseconds, which disables this feature.
Default
0 milliseconds, which disables this feature.
Command Mode
Interface configuration
Usage Guidelines
If a hardware outage lasts longer than the LAPB hardware outage period you select, normal protocol operations will occur. The link will be declared to be down and, when it is restored, a link set up will be initiated.
Example
The following example sets the interface outage period to 100 milliseconds. The link will remain connected for outages equal to or shorter than that period.
encapsulation lapb dte iplapb interface-outage 100lapb k
To specify the maximum permissible number of outstanding frames, called the window size, use the lapb k interface configuration command.
lapb k window-size
Syntax Description
window-size
Frame count. It can be a value from 1 to the modulo size minus 1 (the maximum is 7 if the modulo size is 8; it is 127 if the modulo size is 128). The default is 7 frames.
Default
7 frames
Command Mode
Interface configuration
Usage Guidelines
If the window size is changed while the protocol is up, the new value will take effect only when the protocol is reset. You will be informed that the new value will not take effect immediately.
When using the LAPB modulo 128 mode (extended mode), the window parameter k should be increased to make use of the ability to send a larger number of frames before acknowledgment is required. This is the basis for its ability to achieve greater throughput on high speed links that have a low error rate.
This configured value should match the value configured in the peer X.25 switch. Nonmatching values will cause repeated LAPB REJ frames.
Example
The following example sets the LAPB window size (the k parameter) to ten frames:
interface serial 0lapb modulo lapb k 10lapb modulo
To specify the LAPB basic (modulo 8) or extended (modulo 128) protocol mode, use the lapb modulo interface configuration command.
lapb modulo modulus
Syntax Description
modulus
Either 8 or 128. The value 8 specifies LAPB's basic mode; the value 128 specifies LAPB's extended mode. The default is 8.
Default
Modulo 8
Command Mode
Interface configuration
Usage Guidelines
The modulo parameter determines which of LAPB's two modes is to be used. The modulo values derive from the fact that basic mode numbers information frames between 0 and 7, whereas extended mode numbers them between 0 and 127. Basic mode is widely available and is sufficient for most links. Extended mode is an optional LAPB feature that may achieve greater throughput on high-speed links that have a low error rate.
The LAPB operating mode may be set on X.25 links as well as LAPB Links. The X.25 modulo is independent of the LAPB layer modulo. Both ends of a link must use the same LAPB mode.
When using modulo 128 mode, the window parameter k should be increased to make use of the ability to send a larger number of frames before acknowledgment is required. This is the basis for its ability to achieve greater throughput on high-speed links that have a low error rate.
If the modulo value is changed while the protocol is up, the new value will take effect only when the protocol is reset. The operator will be informed that the new value will not take effect immediately.
Example
The following example configures a high-speed X.25 link to use LAPB's extended mode:
interface serial 1encapsulation x25lapb modulo 128lapb k 40clock rate 2000000Related Command
lapb n1
To specify the maximum number of bits a frame can hold (the LAPB N1 parameter), use the lapb n1 interface configuration command.
lapb n1 bits
Syntax Description
bits
Maximum number of bits in multiples of eight. The minimum and maximum range is dynamically set. Use the ? to view the range.
Defaults
The largest (maximum) value available for the particular interface is the default. The Cisco IOS software dynamically calculates n1 whenever you change the maximum transmission unit (MTU), the L2/L3 modulo, or compression on a LAPB interface.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
CautionThe LAPB n1 parameter provides little benefit beyond the interface MTU and can easily cause link failures if misconfigured. Cisco recommends that this parameter be left at its default value.
The Cisco IOS software uses the following formula to determine the minimum n1 value:
(128 (default packet size) + LAPB overhead + X.25 overhead + 2 bytes of CRC) * 8
The Cisco IOS software uses the following formula to determine for the maximum n1 value:
(hardware MTU + LAPB overhead + X.25 overhead + 2 bytes of CRC) * 8
LAPB overhead is 2 bytes for modulo 8 and 3 bytes for modulo 128.
X.25 overhead is 3 bytes for modulo 8 and 4 bytes for modulo 128.
You need not set n1 to an exact value to support a particular X.25 data packet size. The n1 parameter prevents the processing of any huge frames that result from a "jabbering" interface, an unlikely event.
In addition, the various standards bodies specify that n1 be given in bits rather than bytes. While some equipment can be configured in bytes or will automatically adjust for some of the overhead information present, Cisco devices are configured using the true value, in bits, of n1.
You cannot set the n1 parameter to a value less than that required to support an X.25 data packet size of 128 bytes. All X.25 implementations must be able to support 128-byte data packets. Moreover, if you configure n1 to be less than 2104 bits, you receive a warning message that X.25 might have problems because some nondata packets can use up to 259 bytes.
You cannot set the n1 parameter to a value larger than the default unless the hardware MTU size is first increased.
The X.25 software will accept default packet sizes and CALLs that specify maximum packet sizes greater than what the LAPB layer will support, but will negotiate the CALLs placed on the interface to the largest value that can be supported. For switched CALLs, the packet size negotiation takes place end-to-end through the Cisco router so the CALL will not have a maximum packet size that exceeds the capability of either of the two interfaces involved.
Examples
The following example shows how to use the ? command to display the minimum and maximum n1 value. In this example, X.25 encapsulation has both the LAPB and X.25 modulo set to 8. Any violation of this n1 range results in an "Invalid input" error message.
interface serial 1lapb n1 ?<1080-12056> LAPB N1 parameter (bits; multiple of 8)The following example sets the N1 bits to 16440:
interface serial 0 lapb n1 16440mtu 2048Related Command
A dagger (†) indicates that the command is documented in another chapter.
mtu†
lapb n2
To specify the maximum number of times a data frame can be transmitted (the LAPB N2 parameter), use the lapb n2 interface configuration command.
lapb n2 tries
Syntax Description
Default
20 transmissions
Command Mode
Interface configuration
Example
The following example sets the N2 tries to 50:
interface serial 0 lapb n2 50lapb protocol
Use the lapb protocol interface configuration command to configure the protocol carried on the LAPB line.
lapb protocol protocol
Syntax Description
protocol
Protocol, entered by keyword. It can be one of the following: appletalk, apollo, clns (ISO CLNS), decnet, ip, ipx (Novell IPX), vines, and xns.
Default
IP
Command Mode
Interface configuration
Usage Guidelines
This command is not available when using a multiprotocol LAPB encapsulation.
Example
The following example sets AppleTalk as the only protocol on the LAPB line:
interface serial 1encapsulation lapb lapb protocol appletalkRelated Commands
encapsulation lapb
encapsulation lapb-dce
encapsulation lapb-multilapb t1
To set the retransmission timer period (the LAPB T1 parameter), use the lapb t1 interface configuration command.
lapb t1 milliseconds
Syntax Description
milliseconds
Time in milliseconds. It can be a value from 1 through 64000. The default is 3000 milliseconds.
Default
3000 milliseconds
Command Mode
Interface configuration
Usage Guidelines
The retransmission timer determines how long a transmitted frame can remain unacknowledged before the LAPB software polls for an acknowledgment. The design of the LAPB protocol specifies that a frame is presumed to be lost if it is not acknowledged within T1; a T1 value that is too small may result in duplicated control information, which can severely disrupt service.
To determine an optimal value for the retransmission timer, use the privileged EXEC command ping to measure the round-trip time of a maximum-sized frame on the link. Multiply this time by a safety factor that takes into account the speed of the link, the link quality, and the distance. A typical safety factor is 1.5. Choosing a larger safety factor can result in slower data transfer if the line is noisy. However, this disadvantage is minor compared to the excessive retransmissions and effective bandwidth reduction caused by a timer setting that is too small.
Example
The following example sets the T1 retransmission timer to 2,000 milliseconds:
interface serial 0 lapb t1 2000lapb t4
To set the T4 idle timer, after which the router sends out a Poll packet to determine whether the link has suffered an unsignaled failure, use the lapb t4 interface configuration command.
lapb t4 seconds
Syntax Description
seconds
Number of seconds between reception of the last frame and the transmission of the outgoing Poll. The default value is 0 seconds, which disables the T4 timer feature.
Defaults
0 seconds, which disables the T4 timer feature.
Command Mode
Interface configuration
Usage Guidelines
Any nonzero T4 duration must be greater than T1, the LAPB retransmission timer period.
Example
The following example will poll the other end of an active link if it has been 10 seconds since the last frame was received; if the far host has failed, the service will be declared down after N2 tries are timed out.
interface serial0encapsulation x25lapb t4 10Related Commands
show cmns
To display X.25 Level 3 parameters for LAN interfaces (such as Ethernet or Token Ring) and other information pertaining to CMNS traffic activity, use the show cmns EXEC command.
show cmns [type number]
Syntax Description
Command Mode
EXEC
Sample Display
The following is sample output from the show cmns command for an Ethernet interface:
Router# show cmnsEthernet1 is administratively down, line protocol is downHardware address is 0000.0c02.5f4c, (bia 0000.0c2.5f4c), state R1 Modulo 8, idle 0, timer 0, nvc 1Window size: input 2, output 2, Packet size: input 128, output 128Timer: TH 0Channels: Incoming-only none, Two-way 1-4095, Outgoing-only noneRESTARTs 0/0 CALLs 0+0/0+0/0+0 DIAGs 0/0describes significant fields shown in the display.
Table 13-1 Show CMNS Field Descriptions
Related Command
A dagger (†) indicates that the command is documented in another chapter.
show interfaces serial†
show interfaces serial
To display information about a serial interface, use the show interfaces serial EXEC command.
show interfaces serial number
Syntax Description
Command Mode
EXEC
Sample Displays
The following is a partial sample output from the show interfaces serial command for a serial interface using LAPB encapsulation:
Router# show interfaces serial 1LAPB state is SABMSENT, T1 3000, N1 12056, N2 20, k7,Protocol ip VS 0, VR 0, RCNT 0, Remote VR 0, Retransmissions 2IFRAMEs 0/0 RNRs 0/0 REJs 0/0 SABMs 3/0 FRMRs 0/0 DISCs 0/0shows the fields relevant to all LAPB connections.
Table 13-2 Show Interfaces Serial Fields and Descriptions when LAPB is Enabled
The following is a partial sample output from the show interfaces command for a serial X.25 interface:
Router# show interfaces serial 1X25 address 000000010100, state R1, modulo 8, idle 0, timer 0, nvc 1Window size: input 2, output 2, Packet size: input 128, output 128Timers: T20 180, T21 200, T22 180, T23 180, TH 0Channels: Incoming-only none, Two-way 1-1024, Outgoing-only none(configuration on RESTART: modulo 8,Window size: input 2 output 2, Packet size: input 128, output 128Channels: Incoming-only none, Two-way 5-1024, Outgoing-only none)RESTARTs 3/2 CALLs 1000+2/1294+190/0+0/ DIAGs 0/0The stability of the X.25 protocol requires that some parameters not be changed without a RESTART of the protocol. Any change to these parameters will be held until a RESTART is sent or received. If any of these parameters will change, the configuration on RESTART information will be output as well as the values that are currently in effect.
describes significant fields shown in the display.
Table 13-3 Show Interfaces X25 Field Descriptions
Related Command
show llc2
To display active LLC2 connections, use the show llc2 EXEC command.
show llc2c
Syntax Description
This command has no arguments or keywords.
Command Mode
EXEC
Sample Display
The following is sample output from the show llc2 command:
Router# show llc2TokenRing0 DTE=1000.5A59.04F9,400022224444 SAP=04/04, State=NORMALV(S)=5, V(R)=5, Last N(R)=5, Local Window=7, Remote Window=127ack-max=3, n2=8, Next timer in 7768xid-retry timer 0/60000 ack timer 0/1000p timer 0/1000 idle timer 7768/10000rej timer 0/3200 busy timer 0/9600ack-delay timer 0/3200CMNS Connections to: Address 1000.5A59.04F9 via Ethernet2 Protocol is up Interface type X25-DCE RESTARTS 0/1 Timers: T10 1 T11 1 T12 1 T13 1The display includes a CMNS addendum, indicating that LLC2 is running with CMNS. When LLC2 is not running with CMNS, the show llc2 command does not display a CMNS addendum.
describes significant fields shown in the display.
Table 13-4 Show LLC2 Field Descriptions
show x25 map
To display information about configured address maps, use the show x25 map EXEC command.
show x25 map
Syntax Description
This command has no arguments or keywords.
Command Mode
EXEC
Usage Guidelines
The show x25 map command shows information about the following:
•
•
•
•
Sample Display
The following is sample output from the show x25 map command:
Router# show x25 mapSerial0: X.121 1311001 <--> ip 131.108.170.1PERMANENT, BROADCAST, 2 VCS: 3 4*Serial0: X.121 1311005 <--> appletalk 128.1PERMANENTSerial1: X.121 1311005 <--> bridgePERMANENT, BROADCASTSerial2: X.121 001003 <--> apollo 1.3,appletalk 1.3,ip 131.108.1.3,decnet 1.3,novell 1.0000.0c04.35df,vines 00000001:0003,xns 1.0000.0c04.35df,clnsPERMANENT, NVC 8, 1 VC: 1024The display shows that four maps have been configured for the router, two for serial interface 0, one for serial interface 1, and one for the serial interface 2 (which maps eight protocols to the host).
describes fields shown in the display.
Table 13-5 Show X25 Map Field Description
show x25 remote-red
To display the one-to-one mapping of the host IP addresses and the remote BFE device's IP addresses, use the show x25 remote-red EXEC command.
show x25 remote-red
Syntax Description
This command has no arguments or keywords.
Command Mode
EXEC
Sample Display
The following is sample output from the show x25 remote-red command:
Router# show x25 remote-redEntry REMOTE-RED REMOTE-BLACK INTERFACE1 21.0.0.3 21.0.0.7 serial32 21.0.0.10 21.0.0.6 serial13 21.0.0.24 21.0.0.8 serial3describes significant fields shown in the display.
Table 13-6 Show X25 Remote-Red Display Field Description
show x25 route
To display the X.25 routing table, use the show x25 route EXEC command.
show x25 route
Syntax Description
This command has no arguments or keywords.
Command Mode
EXEC
Sample Display
The following is sample output from the show x25 route command:
Router# show x25 routeNumber X.121 CUD Forward To1 1311001 Serial0, 0 uses2 1311002 131.108.170.10, 0 uses3 1311003 00 alias Serial0, 2 usesdescribes significant fields shown in the display.
Table 13-7 Show X25 Route Display Field Description
Related Command
show x25 vc
To display information about active switched virtual circuits (SVCs) and permanent virtual circuits (PVCs), use the show x25 vc EXEC command.
show x25 vc [lcn]
Syntax Description
Command Mode
EXEC
Usage Guidelines
To examine a particular virtual circuit, add an LCN argument to the show x25 vc command.
This command displays information about virtual circuits that are used for any of the following:
•
•
•
•
The connectivity information displayed will vary according to the traffic carried by the virtual circuit. For multiprotocol circuits, the output varies depending on the number and identity of the protocols mapped to the X.121 address and the encapsulation method selected for the circuit.
Sample Displays
This section provides three sample displays and tables that describe the fields in each display.
The following sample display shows a virtual circuit that is being used to encapsulate traffic between the router and a remote host:
Router# show x25 vc 1024SVC 1024, State: D1, Interface: Serial0Started 0:00:31, last input 0:00:31, output 0:00:31Connects 170090 <-->compressedtcp 131.108.170.90ip 131.108.170.90multiprotocol CUD PID, standard Tx data PID, Reverse chargedWindow size input: 2, output: 2Packet size input: 128, output: 128PS: 5 PR: 5 ACK: 4 Remote PR: 5 RCNT: 1 RNR: FALSEWindow is closedRetransmits: 0 Timer (secs): 0 Reassembly (bytes): 0Held Fragments/Packets: 0/0Bytes 505/505 Packets 5/5 Resets 0/0 RNRs 0/0 REJs 0/0 INTs 0/0describes the general fields shown in the output; describes the fields specific to encapsulation virtual circuits shown in the output.
Table 13-8 Show X25 VC Field Descriptions
SVC 1024
Identifies the type (switched or permanent) and the number of the virtual circuit.
State
State of the virtual circuit (which is independent of the states of other virtual circuits); D1 is the normal ready state. (See the International Telecommunication Union Telecommunication Standardization Sector (ITU-T)1 X.25 Recommendation for a description of virtual circuit states.)
Interface
Interface or subinterface on which the virtual circuit is established.
Started
Time elapsed since the virtual circuit was created.
last input
Time of last input.
output
Shows time of last output.
Connects...<-->...
Describes the traffic-specific connection information. See , , and for more information.
Window size
Window sizes for the virtual circuit.
Packet size
Maximum packet sizes for the virtual circuit.
PS
Current send sequence number.
PR
Current receive sequence number.
ACK
Last acknowledged incoming packet.
Remote PR
Last PR number received from the other end of the circuit.
RCNT
Count of unacknowledged input packets.
RNR
State of the Receiver Not Ready flag; this field is true if the network sends a receiver-not-ready packet.
Window is closed
This line appears if the router cannot transmit any more packets until the X.25 layer 3 peer has acknowledged some outstanding packets.
Retransmits
Number of times a supervisory packet (RESET or CLEAR) has been retransmitted.
Timer
A nonzero time value indicates that a control packet has not been acknowledged yet or that the virtual circuit is being timed for inactivity.
Reassembly
Number of bytes received and held for reassembly (packets with the More bit set are reassembled into datagrams for encapsulation virtual circuits; switched X.25 traffic is not reassembled).
Held Fragments/Packets
Number of X.25 data fragments to transmit to complete an outgoing datagram, and the number of datagram packets waiting for transmission.
Bytes
Total number of bytes sent and received. The Packets, Resets, RNRs, REJs, and INTs fields show the total sent and received packet counts of the indicated types. (RNR is Receiver Not Ready, REJ is Reject, and INT is Interrupt).
1 The ITU-T carries out the functions of the former Consultative Committee for International Telegraph and Telephone (CCITT).
describes the connection description fields for virtual circuits carrying encapsulation traffic.
Table 13-9 Show X25 VC Encapsulation Traffic Field Descriptions
