LAPB, X.25, and X.25 Switch configuration commands (1)

1. clear x25 counters
Clears all statistics of an X.25 API.
Clear x25 counters interface-type interface-number
Parameter description]
Interface-type is the interface type.
Interface-number is the interface number.
Command mode]
Privileged user mode
User Guide]
You can use this command to restore all statistics of an X.25 interface to the initial state of 0), so that you can observe changes in network data traffic.
Example]
Clear all statistics of the X.25 interface serial0.
Quidway # clear x25 counters serial 0
Related commands]
Show interface serial, show x25 interface serial
2. clear x25 vc
Clear the temporary virtual circuit SVC on an X.25 interface or recover the permanent virtual circuit PVC.
Clear x25 vc interface-type interface-number [lcn]
Parameter description]
Interface-type is the type of the X.25 interface.
Interface-number is the number of the X.25 Interface.
Lcn is the number of the virtual circuit to be cleared or restored (optional)
Default condition]
If the parameter lcn is selected, only the virtual circuit numbered lcn of the X.25 interface is cleared SVC) or restored PVC ). If the parameter lcn is not selected, all SVC on the X.25 interface will be cleared, and all PVC will be restored, that is, a restart event will occur ).
Command mode]
Privileged user mode
User Guide]
Use this command to perform real-time maintenance on the virtual circuit of an X.25 interface, and initiate a clearance procedure for the specified virtual circuit for SVC) or recovery procedure for PVC ), or initiate a restart procedure for the specified interface. Note that this command takes effect only after the X.25 protocol is negotiated.
Example]
How can I enable the X.25 interface serial1 to generate a record?
Quidway # clear x25 vc serial 1
Related commands]
Show interface serial, show x25 vc, x25 idle
3. encapsulation lapb
The interface link layer protocol is encapsulated as the LAP protocol.
Encapsulation lapb [dte | dce] [ip]
Parameter description]
Dte and dce indicate how LAPB works.
The ip address is the network layer protocol hosted by LAPB.
Default condition]
The default mode of LAPB is DTE, and the network layer IP protocol is supported by default.
Command mode]
Interface Configuration Mode
User Guide]
Although LAPB is a layer-2 protocol of X.25, it can be used as an independent link layer protocol for serial port encapsulation and simple data transmission. Generally, the LAPB protocol can be encapsulated when two routers are directly connected through a leased line. At this time, one end works in the DTE mode and the other end works in the DCE mode.
Example]
The interface Serial0 encapsulates LAPB and works in the DCE mode.
Quidway (config-if-Serial0) # encapsulation lapb dce
Related commands]
Show interface
4. encapsulation x25
This command encapsulates the specified interface with the X.25 protocol, and later the datagram that comes in and out of this interface will be encapsulated and transmitted by the X.25 protocol. The interface that executes this command is called the X.25 interface.
Encapsulation x25 [dte | dce] [ietf | ddn | bfe]
Parameter description]
Dte specifies that the interface works in the DTE mode, which is also the default work mode)
Dce specifies that this interface works in the DCE mode)
Ietf specifies that the interface encapsulates the datagram in the IETF RFC-1356 format, which is also optional for the default Encapsulation Format)
Ddn specifies that the interface encapsulates the datagram according to the DDN X.25 standard service mode. Optional)
Bfe specifies that this interface encapsulates data packets in BFE mode (optional)
Default condition]
The interface is encapsulated as PPP by default. When the X.25 protocol is encapsulated, the default operation mode is dte ietf.
Command mode]
Interface Configuration Mode
User Guide]
For both ends of an X.25 connection, one end is logically required to be DTE and the other end is DCE, this is because the DTE and DCE are not physically related to the DTE and DCE as electrical properties. Generally, if a user device is connected to the X.25 public group network, the User device is generally used as the DTE side, and the DCE side is generally used as the public branch network. However, when the two routers are simply connected back-to-back directly, although the two ends of the connection are both user-device routers ), however, it should be ensured that the two ends of the connection are logically DTE and DCE, that is, the two routers that are directly connected back-to-back work in the DTE mode, and the other work in the DCE mode ).
Once an X.25 interface is re-encapsulated, all the parameters of the X.25 protocol you have configured, in addition to address ing, are retained, the rest will be restored to the default value. That is to say, when You encapsulate this interface as an X.25 interface again, you can continue to use address-only ing in the configuration you used.
In common applications, if there are no special requirements, please use the IETF format encapsulation of the datagram.
Example]
Encapsulate the interface Serial0 as an X.25 interface in the dte ietf mode.
Quidway (config-if-Serial0) # encapsulation x25 dte ietf
Related commands]
Show interface
5. lapb k
Configure the parameter K in the LAPB window
Lapb k-value
Parameter description]
K-value indicates the number of ordered native bytes frames to be confirmed by DTE or DCE at any specified time. If the modulus is 8, the window parameter K ranges from 1 ~ 7. If the modulus is 128, the window parameter K ranges from 1 ~ 127.
Default condition]
The default value of window parameter K is 7.
Command mode]
Interface Configuration Mode
User Guide]
The value of window parameter K must be determined by the modulo value.
Example]
Set the parameter K of the LAPB window on the Interface Serial0 to 7.
Quidway # (config-if-Serial0) # lapb k 7
Related commands]
Lapb modulo
6. lapb modulo
Configure the LAPB frame number method, also known as modulus ).
Lapb modulo {128 | 8}
Parameter description]
The modulo 128 and modulo 8 are numbered respectively.
Default condition]
The default frame number mode of LAPB is modulo 8.
Command mode]
Interface Configuration Mode
User Guide]
There are two types of LAPB frame numbers: mod 8 and mod 128. Each data frame I frame) is numbered sequentially. numbers can be ranging from 0 to a modulus minus 1, and the serial number Loops within the entire modulus range.
Mode 8 is the basic method. All standard LAPB is implemented and is sufficient for most links. Mode 128 can reach a high throughput rate on high-speed links or low-error links. This is because the maximum value of the window parameter K of LAPB is limited by the modulus, and the maximum value is reduced by 1, K specifies the maximum number of frames that can be sent before receiving confirmation.
Example]
Set the LAPB frame number on the Serial0 interface to Mode 8.
Quidway (config-if-Serial0) # lapb modulo 8
Related commands]
Lapb k
7. lapb n1
Configure the LAPB parameter N1.
Lapb n1 n1-value
Parameter description]
N1-value represents the N1 value, in bits, range: 1080 ~ 12056.
Default condition]
The default value of the LAPB parameter N1 is 2104.
Command mode]
Interface Configuration Mode
User Guide]
The N1 value indicates the maximum number of bits of the I frame that the DCE or DTE wants to accept from the DTE or DCE. The value should be the maximum transmission unit MTU) add 8 times the total number of bytes of the protocol header. This value specifies the maximum length of the transmission frame and determines the maximum length of the encapsulated X.25 group.
Example]
Set the LAPB parameter N1 on the Serial0 interface to 1080.
Quidway (config-if-Serial0) # lapb n1 1080
8. lapb n2
Configure LAPB parameter N2
Lapb n2 n2-value
Parameter description]
The n2-value represents the N2 value in the range of 1 ~ 255.
Default condition]
The default value of LAPB parameter N2 is 5.
Command mode]
Interface Configuration Mode
User Guide]
N2 indicates the maximum number of attempts by DCE or DTE to successfully send a frame to DTE or DCE.
Example]
Set the LAPB parameter N2 on the Serial0 interface to 20.
Quidway (config-if-Serial0) # lapb n2 20
9. lapb t1
Configure the LAPB system timer T1
Lapb t1 t1-value
Parameter description]
T1-value is the value of timer T1, unit ms, range 1 ~ 64000.
Default condition]
The default value of the LAPB system timer T1 is 2000 ms.
Command mode]
Interface Configuration Mode
User Guide]
T1 is the sending timer. When the T1 timer arrives, DTE (DCE) starts resending. The value of T1 should be greater than the value of sending a frame to receive it. Why?
Example]
Set the timer T1 of lapb on the Serial0 interface to 1000 ms.
Quidway (config-if-Serial0) # lapb t1 1000
Related commands]
Lapb t2, lapb t3
10. lapb t2
Configure the LAPB system timer T2.
Lapb t2 t2-value
Parameter description]
T2-value for the timer T2 value, unit ms, range 1 ~ 64000.
Default condition]
The default value of the LAPB system timer T2 is 1000 ms.
Command mode]
Interface Configuration Mode
User Guide]
T2 is the receiving timer. After the T2 timer arrives, DTE (DCE) must send a validation frame so that the other DTE (DCE) before the T1 timer times out, you can receive the verification frame (T2 $ # @ 60; T1 ).
Example]
Set the timer T2 of lapb on the Serial0 interface to 2000 ms.
Quidway (config-if-Serial0) # lapb t2 2000
Related commands]
Lapb t1
11. lapb t3
Configure the LAPB system timer T3.
Lapb 3 t3-value
Parameter description]
T3-value for the timer T3 value, unit ms, range 0 ~ 64000.
Default condition]
The default value of the LAPB timer T3 is 0 ms.
Command mode]
Interface Configuration Mode
User Guide]
T3 is the idle channel timer. When the T3 timer arrives, DCE reports to the grouping layer that the link has a long idle channel status, t3 should be greater than the timer T1 (T3 $ # @ 62; T1) in DCE ). If T3 is 0, the timer does not take effect.
Example]
Configure the T3 timer of lapb on the Serial0 interface to 10000 ms.
Quidway (config-if-Serial0) # lapb t3 10000
Related commands]
Lapb t1
12. show x25 alias
The X.25 alias table is displayed.
Show x25 allias
Command mode]
Privileged user mode, global configuration mode, interface configuration mode, and Routing Protocol configuration mode.
User Guide]
Use this command to view all aliases set for all X.25 interfaces.
Example]
Quidway # show x25 alias
Alias for Serial0:
Alias for Serial1:
Alias-1 :$ 20112405 $ strict
Alias-2: $20112450 left
Alias-3: 20112450 $ right
The information shown above indicates that no alias is set for the X.25 interface Serial0; For the X.25 interface Serial1, three aliases are set, which are in the matching mode of $20112405 $), $20112405 match mode is left-aligned match), 20112405 $ match mode is right-aligned match ).
Related commands]
Show x25 interface, x25 alias
13. show x25 interface
Displays X.25 interface information.
Show x25 interfae serial [number]
Parameter description]
Number is stringizen screwed?
Default condition]
If no serial number is specified, all X.25 interfaces are displayed.
Command mode]
Privileged user mode, global configuration mode, interface configuration mode, and Routing Protocol configuration mode.
User Guide]
After you configure some X.25 parameters and attributes, or enable or disable some X.25 functions, you can use this command to observe the results of your operation. With this command, you can easily obtain all X.25 configuration information on an interface.
Example]
Displays the X.25 interface information of the Serial0 interface.
Quidway # show x25 interface serial 0
Encapsulation X.25 dte ietf, address is, state Ready, modulo 8
Input/output: window sizes 2/2, packet sizes 128/128
Channels: Incoming-only 0-0, Two-way 1-1024, Outgoing-only 0-0
Timers: T20 180, T21 200, T22 180, T23 180, T28 300, Idle_Timer 0
New configuration (will be valid tive after restart): modulo 8
Input/output: window sizes 2/2, packet sizes 128/128
Channels: Incoming-only 0-0, Two-way 1-1024, Outgoing-only 0-0
Statistic: Restarts 0 (Restart Collisions 0)
Refused Incoming Call 0, Failing Outgoing Call 0
Input/output: RESTART 0/0 CALL 0/0 DIAGNOSE 0/0
DATA 0/0 INTERRUPT 0/0 Bytes 0/0
RR 0/0 RNR 0/0 REJ 0/0
Invalid Pr: 0 Invalid Ps: 0 Unknown: 0
Lapb dte, module 8, k 7, N1 2104, N2 5
Timer: T1 2000, T2 1000, T3 0 (milliseconds)
State DISCONNECT, VS 0, VR 0, Remote VR 0
IFRAME 0/0, RR 0/0, RNR 0/0, REJ 0/0
FRMR 0/0, SABM 0/0, DM 0/0, UA 0/0
DISC 0/0, invalid ns 0, invalid nr 0, link resets 0
The LAPB and X.25 information displayed by the show x25 interface command are shown in Table 3-1 and 3-2, respectively.
Table 3-1 show x25 interface Information
　
Table 3-2 X.25 information displayed by the show x25 interface command
　
Related commands]
Show interface
14. show x25 map
The X.25 address ing table is displayed.
Show x25 map
Command mode]
Privileged user mode, global configuration mode, interface configuration mode, and Routing Protocol configuration mode.
User Guide]
To configure X.25 address ing, you can use either the x25 map command or the x25 pvc command in implicit mode. You can use the show x25 map command to view all address ing.
Example]
Quidway # show x25 map
Serial0: X.121 20112450 $ # @ 60; -- $ # @ 62; ip address 202.38.165.19 SVC_MAP
No VC attched
Facility:
ACCEPT_REVERSE;
BROADCAST;
PACKET_SIZE: I 512 O 512;
Serial1: X.121 20112451 $ # @ 60; -- $ # @ 62; ip address 202.38.166.20 PVC_MAP
1 VC: 3 *
Facility:
BROADCAST;
WINDOW_SIZE: I 5 O 5;
Table 3-3 describes the meaning of each domain in the preceding address ing information.
Table 3-3 X.25 address ing information
　
Related commands]
X25 map, x25 pvc, show x25 interface
15. show x25 switch-vc-table
The X.25 switching circuit table is displayed.
Show x25 switch-vc-table
Command mode]
Privileged user mode, global configuration mode, interface configuration mode, and Routing Protocol configuration mode.
User Guide]
This command displays the X.25 Circuit Used for switching.
Example]
Quidway (config) # Show x25 switch-vc-table
#1 (In: Serial0-vc1024) <--> (Out: Serial1-vc1)
#2 (In: Serial1-vc1024) <--> (Out: Serial0-vc1)
It indicates that there are two records in the current switching circuit table:
From the 1024 virtual circuit of Serial0, from the 1 virtual circuit of Serial1;
From the 1024 virtual circuit of Serial1, from the 1 virtual circuit of Serial0.
Related commands]
X25 pvc, x25 route
16. show x25 route
The X.25 exchange route table is displayed.
Show x25 route
Command mode]
Privileged user mode, global configuration mode, interface configuration mode, and Routing Protocol configuration mode.
User Guide]
The command displays the following information: virtual circuit number and its switching interface.
Example]
Quidway (config) # Show X25 route
Number X.121 CUD FowardTo
#1 1 Serial0
#2 2 Serial1
The above information indicates that the call with the destination X.121 address 1 will be switched to the interface Serial0 output, and the call with the destination X.121 address 2 will be switched to the interface Serial1 output.
Related commands]
Show x25 interface, x25 routing, x25 pvc, x25 route
17. show x25 vc
Displays the X.25 virtual circuit.
Show x25 vc [lcn]
Parameter description]
Lcn is the logical channel number.
Default condition]
If no logical channel number is specified, all virtual circuits are displayed by default.
Command mode]
Privileged user mode, global configuration mode, interface configuration mode, and Routing Protocol configuration mode.
User Guide]
SVC is set up on a temporary basis by calling X.25 when there are data transmission requirements. PVC is manually configured and always exists regardless of whether there are data transmission requirements. When the vro works in the X.25 switching mode, virtual circuits are also established to transmit the exchanged data. These virtual circuits can use this command to view information, but they are different in some fields where information is displayed.
Example]
Quidway # show x25 vc
SVC 1, State: TRANSFER, Interface: Serial0
Started: 1:48:11, Last input: 0:45:57, Last output: 0:45:59
Connects: X.121 20112450 $ # @ 60; -- $ # @ 62; ip address 202.38.165.19
Window size: input 5 output 5
Packet Size: input 128 output 128
PS: 0 PR: 0 ACK: 0 Remote PR: 0 RCNT: 0
RNR: FALSE Reset times: 0
Input/output: DATA 1154/1022 INTERRUPT 0/0 Bytes 1569732/1435638
RR 143/165 RNR 0/0 REJ 0/0
Snd Queue: Current length 0 Max length 50 Drops 0
Rcv Queue: Current length 0 Max length 50 Drops 0
PVC 3, State: TRANSFER, Interface: Serial1
Started: 1:48:11, Last input: 0:30:09, Last output: 0:30:17
Connects: X.121 20112451 $ # @ 60; -- $ # @ 62; ip address 202.38.166.20
Window size: input 5 output 5
Packet Size: input 128 output 128
PS: 0 PR: 0 ACK: 0 Remote PR: 0 RCNT: 0
RNR: FALSE Reset times: 0
Input/output: DATA 0/0 INTERRUPT 0/0 Bytes 0/0
RR 0/0 RNR 0/0 REJ 0/0
Snd Queue: Current length 0 Max length 50 Drops 0
P> Rcv Queue: Current length 0 Max length 50 Drops 0
The above information indicates that a temporary virtual circuit exists on the X.25 interface Serial0, and its number is 1. On the X.25 interface Serial1, there is a permanent virtual circuit with its number being 3. The following table describes the meanings of each domain in the preceding information:
Table 3-4 X.25 virtual circuit information
　
Related commands]
Clear x25 vc, show x25 interface serial, x25 pvc
18. x25 accept-revers
Snd Queue
Related commands]
Clear x25 vc, show x25 interface serial, x25 pvc
18x25 accept-reverse
Configure an X.25 interface to accept all calls that carry the "reverse billing request" to the interface. You can disable this function by adding the no keyword before the command, after the call is closed, all such calls will trigger a clearing procedure for this call.
[No] x25 accept-reverse
Default condition]
This function is disabled by default.
Command mode]
Interface Configuration Mode
User Guide]
This function does not affect any calls that do not carry the "reverse billing request" user facility. You can enable the "Accept call carrying the reverse billing request" function on an X.25 interface, all such calls will be accepted. You can also enable this function for an address ing using the accept-reverse option in the x25 map command, only calls that reach this interface for this address ing are accepted, while other such calls refer to calls that carry reverse billing requests but are not mapped to this address) will be cleared. You can run the show x25 interface serial command to check whether the function of an X.25 interface is enabled.
Example]
Enable the "receive calls carrying reverse billing requests" function for the interface Serial0.
Quidway (config-if-Serial0) # x25 accept-reverse
Related commands]
Show x25 interface serial, x25 map
19. x25 address
Configure or delete the X.121 address for an X.25 interface.
[No] x25 address x.121-address
Parameter description]
X.121-address is the X.121 address of the interface.
Default condition]
If the data Encapsulation Format of the X.25 interface is IETF, the interface has no address. If the data Encapsulation Format of the X.25 interface is BFE or DDN, the X.121 address of this interface is obtained dynamically based on the IP address of this interface, and such an X.121 address cannot be changed.
Command mode]
Interface Configuration Mode
User Guide]
If the vro is connected to X.25, it will be swollen and published. 121 address. If you simply use two vrouters for back-to-back direct connection, you can specify the valid X.121 address at will. If you only want the vro to work in the exchange mode, the X.121 address is not used.
When you reconfigure the X.121 address for an X.25 interface, you do not need to delete the original X.121 address first. The new address will automatically overwrite the old address. After You encapsulate an X.25 interface again, the configured X.121 address will be deleted and will only take effect after reconfiguration.
NOTE: For the format, IP address and dynamic conversion of X.121 address, please refer to ITU-T recommendation X.121 and related RFC documentation.
Example]
The interface Serial0 is encapsulated as the X.25 protocol, and the X.121 address is configured as 20112451.
Quidway (config) # interface serial 0
Quidway (config-if-Serial0) # encapsulation x25
Quidway (config-if-Serial0) # x25 address 20112451
Related commands]
Show interface, show x25 interface
20. x25 alias
Specifies or deletes aliases matching various modes for an X.25 interface.
[No] x25 alias match-type alias-string
Parameter description]
Match-type is the matching method of this alias. There are nine matching methods available:
Free: free matching
Free-ext: extended free Match
Left: left-aligned matching
Left-ext: Extended left-aligned matching
Right: right-aligned matching
Right-ext: Extended right-aligned matching
Strict
Whole: full match
Whole-ext: Extended exact match
　
Alias-string is an alias string
Default condition]
X.25 interface has no alias by default
Command mode]
Interface Configuration Mode
User Guide]
When an X.25 call is forwarded across different networks, different X.25 networks may perform some operations on the destination address (called DTE address) carried by the call group, for example, you can regularly add or remove prefixes and suffixes. In this case, you need to set an interface alias for the router to adapt to this change. If the network has such a function, consult your provider and decide whether to enable the alias function.
For more information about how to match an X.25 alias, see the "LAPB, X.25, and X.25 interchange configuration" section in the Configuration Guide.
Example]
Encapsulate the interface Serial0 as X.25 protocol, configure X.121 address 20112451 for it, and set two aliases with different matching methods for it.
Quidway (config) # interface serial 0
Quidway (cofnig-if-Serial0) # encapsulation x25
Quidway (cofnig-if-Serial0) # x25 address 20112451
Quidway (cofnig-if-Serial0) # x25 alias 20112451 $
Quidway (cofnig-if-Serial0) # x25 alias $20112451
After the above configuration, for a call destined for 20112451, no matter whether the network is prefix or suffix-added, as long as the call can reach the local X.25 interface Serial0, all calls are accepted.
Related commands]
Show x25 alias, show x25 interface serial, x25 address
21. x25 check-response-address
Configure whether to check the address code group field in the call Acceptance Group or call connection group of X.25.
[No] x25 check-response-address
Default condition]
By default, the system does not check the address code group field in the call Acceptance Group.
Command mode]
Interface Configuration Mode
User Guide]
Some networks require that the called DTE cannot carry the called DTE address field when returning a call Acceptance Group to the called DTE. Some require that the called DTE address field cannot be carried, in some cases, neither of them can be carried, but in some cases, both must be carried. To adapt to various situations, the X.25 of the Quidway (R) series routers provides you with this function, you can decide whether to disable or enable this function after implementing it to your access service provider.
Example]
Enable this function for the X.25 interface Serial0:
Quidway (config-if-Serial0) # x25 check-response-address
Related commands]
Show x25 interface, x25 response-called-address, x25 response-calling-address
22. x25 default
Set or delete the upper-layer protocols that are carried by X.25 by default for an X.25 interface.
[No] x25 default protocol-type
Parameter description]
Protocol-type indicates the protocol type.
Default condition]
X.25 by default, the bearer network protocol is IP.
Command mode]
Interface Configuration Mode
User Guide]
For a call that does not carry the call user data or contains the call user data that cannot be parsed, The X.25 of the Quidway (R) series router needs to use this parameter to determine the upper-layer protocol of the call. If this parameter is not set, all such incoming calls will be cleared.
Example]
Set the default bearer upper-layer protocol of Serial0 of X.25 interface to IP protocol.
Quidway (config-if-Serial0) # x25 default ip
23. x25 facility
Sets or deletes optional user options for an X.25 interface. If an option is set, all X.25 calls originating from this X.25 interface will carry corresponding information fields in the call group.
[No] x25 facility-type facility-value
Parameter description]
Facility-type is the user facility type.
Facility-value is the parameter required by the user's facility.
Default condition]
No user facilities are set by default.
Command mode]
Interface Configuration Mode
User Guide]
The user facilities supported by X.25 of the Quidway (R) series routers and their required parameters are shown in Table 3-5.
Table 3-5 X.25 user facility types and their parameters

The user facilities set using this command are valid for all calls originating from this X.25 interface; you can also use the x25 map protocol-name protocol-address x.121-address facility-type facility-value command to set user options for an X.25 call originating from an address ing.
Example]
Specify all calls initiated from the X.25 interface Serial0 and negotiate with the peer traffic control parameters.
Quidway (config-if-Serial0) # x25 facility packetsize 512
Quidway (config-if-Serial0) # x25 facility windowsize 5 5
Related commands]
Show x25 interface, x25 map