The X.25 Transport Protocol (XTP) transports X.25 traffic over TCP/IP. XTP allows existing X.25 devices to communicate over a TCP/IP backbone and migrate from an X.25 network to a network of your choice.

This document provides an overview of XTP. It includes a diagram of how your network might look before using XTP and how the same network would look after using XTP. It also shows how to configure XTP and describes configuration and monitoring commands.

This document includes the following sections:

XTP Overview

To enable this, you use routers at the server and remote locations to encapsulate the data and deliver the X.25 packets between the clients and server via TCP/IP.

Figure 28 shows a typical network configuration before and after using XTP. In a typical configuration, the X.25 clients might be ATM banking machines.

Configuration Information

For example, in Figure 28, you must configure X.25 clients on the

• Remote routers — routers that connect the X.25 clients to the TCP/IP network that is used to access the X.25 server.

• Concentrator router — the router that connects the X.25 server to the TCP/IP network that is used to access the remote router.

• Local DTEs

• Peer routers

• Remote DTEs

• PVCs

Local DTEs

Peer Routers

• To the Concentrator router — the two Remote routers are the peer routers.

• To the two Remote routers — the Concentrator router is the peer router.

Remote DTEs

You must configure a unique internal IP address for each peer router. For example, in Figure 28, the Concentrator router must know the unique IP address of each Remote router and each Remote router must know the IP address of the Concentrator router.

PVC

A PVC, in XTP context, is a PVC from a local X.25 DTE node to a remote X.25 DTE.

When you configure a router for PVCs, you must map the IP address of the peer router and the PVC number of the remote and local DTE.

Displaying the XTP Prompts

Config> xtp
XTP config>

Monitor>protocol xtp
X.25 Transport Console
XTP>

This configuration shows three routers, the Concentrator router, Remote 1 router, and Remote 2 router. To get XTP up and running on this network, you need to perform the following steps for each of these routers.

• Set the data-link type

• Configure IP

• Configure X.25

• Configure XTP

You can enter list devices at the Config> prompt to see a list of configured interface numbers.

Config>set data-link X25 
Interface Number [0]? 1
Config>set data-link x25 
Interface Number [0]?2 
Config>set data-link ppp 
Interface Number [0]?3 

1. Display the IP config> prompt.

Config>protocol ip
IP config>

2. Add an IP address for the IP interface (interface 3 in Figure 29).

IP config>add address
Which net is this address for [0]? 3
New address [0.0.0.0]? 128.185.100.7
Address mask [255.255.0.0]? 255.255.255.1

3. Set the internal IP address of this router. Each router identifies its peer routers by the internal IP address of the peer routers.

IP config>set internal-ip-address
Internal IP address [0.0.0.0]? 128.185.100.1

4. Exit the IP config> prompt.

IP config>exit
Config>

Config>network 3                      
PPP interface configuration  
PPP config>

The parameters you need to configure depend on your network topology. For details on the X.25 parameters, see X.25 Commands.

Interface 1

1. At the Config> prompt, enter network followed by the number of the X.25 interface. In this example, it is interface 1.

Config>network 1             
X.25 User Configuration 
X.25 Config>

2. Specify the network address by entering set address (X.25 node address). In Figure 29, the node address (DTE address) is 100.

X.25 Config>set address 100

3. Enter set clocking followed by internal or external based on your router type.

X.25 Config>set clocking internal

4. Enter set speed followed by the access rate (line speed).

X.25 Config>set speed            
Access rate in bps  [9600]? 19200 

5. Enter set equipment-type and specify whether the frame and packet levels act as DCE or DTE.

X.25 Config>set equipment-type dce  

6. Enter set pvc and define the lowest and highest PVC you are using.

X.25 Config>set pvc low 1   
X.25 Config>set pvc high 1  

7. Enter add pvc to define individual PVCs.

X.25 Config>add pvc
Protocol [IP]? xtp
Packet Channel [1]?
Destination X.25 Address []? 101
Window Size [2]?
Packet Size [128]

1. At the Config> prompt, enter network followed by the number of the X.25 interface. In Figure 29, it is 2.

Config>network 2             
X.25 User Configuration 
X.25 Config>

2. Use the procedures in the Interface 1 section to set the following parameters for interface 2:

• Address = 200

• Clocking = internal

• Speed = 19200

• Equipment = dce

3. Enter set svc and define the lowest and highest SVC you are using.

There are three types of SVCs: two-way, inbound, and outbound. The default is svc low-two-way = 1 and svc high-two-way = 64. All other SVC types default to 0. For further information on SVCs and PVCs, see X.25 Commands.

X.25 Config>set svc low-inbound 0
X.25 Config>set svc high-inbound 0
X.25 Config>set svc low outbound 0
X.25 Config>set svc high outbound 0
X.25 Config>set svc low-two-way 1
X.25 Config>set svc high-two-way 1

4. Configure XTP to run over the X.25 interface. Enter add protocol at the X.25 Config> prompt.

X.25 Config>add protocol
Protocol [IP]?xtp
Window Size [2]?
Default Packet Size [128]?
Maximum Packet Size [256]??

5. Exit the X.25 Config> prompt.

X25 Config> exit
Config>

To view the configuration values, enter list detailed at the X.25 Config> prompt. To set the default values for the national personality, enter set national-personality at the X.25 Config> prompt. For more information, see X.25 Commands.

Configuring XTP

If you need further XTP command information, see XTP Commands.

Note: When configuring your network for XTP, remember that the peer routers are always the routers you are communicating with over TCP/IP. Therefore, the peer router can differ depending on the point of view. In Figure 29, the peer router to Remote 1 router and Remote 2 router is the Concentrator router.

1. To access the XTP config> prompt, enter protocol xtp at the Config> prompt.

2. Add interface 1 to the XTP configuration. Enter add local-dte at the XTP Config> prompt.

XTP config>add local-dte
Interface number [0]? 1
DTE address []? 101
DTE address []?

3. Add interface 2 to the XTP configuration. Enter add local-dte at the XTP Config> prompt.

XTP config>add local-dte
Interface number [0]? 2
DTE address []? 201
DTE address []?

4. Add Remote 1 router (as the peer router). Enter add peer-router and enter the IP address of this router.

XTP config>add peer-router
Router's internal IP Address [0.0.0.0]? 128.185.100.2

5. Add the remote DTE for Remote 1 router. Enter add remote-dte and enter the IP and DTE address of this DTE.

XTP config>add remote-dte
Peer router's internal IP Address [0.0.0.0]? 128.185.100.2 
DTE address []? 301                                          
DTE address []? 

6. Add Remote 2 router (as the peer router). Enter add peer-router and enter the IP address of this router.

XTP config>add peer-router
Router's internal IP Address [0.0.0.0]? 128.185.100.3

7. Add the remote DTEs for Remote 2 router. Enter add remote-dte and enter the IP and DTE addresses of this DTE.

XTP config>add remote-dte
Peer router's internal IP Address [0.0.0.0]? 128.185.100.3 
DTE address []? 401                                          
DTE address []? 402
DTE address []? 403                                          
DTE address []? 404
DTE address []?

Remote 1 Router

*config

Config>set data-link x25 1
Config>set data-link ppp 2
Config>network 1
X.25 Config>set address 300
X.25 Config>set clocking internal
X.25 Config>set speed 19200
X.25 Config>set equipment-type dce
X.25 Config>set pvc low 1
X.25 Config>set pvc high 1
X.25 Config>add pvc
	Protocol [IP]? xtp
	Packet Channel [1]? 1
	Destination X.25 Address []? 301
Window Size [2]? 
	Packet Size [128]? 
X.25 Config>exit
Config>
Config>protocol ip
IP config>add address
	Which net is this address for [0]? 2
	New address [0.0.0.0]? 128.185.100.8
	Address mask [255.255.0.0]? 255.255.255.0

IP config>set internal-ip-address
Internal IP address [0.0.0.0]? 128.185.100.2
IP Config>exit
Config>

Config>protocol xtp
XTP config>add local-dte
Interface number [0]? 1
DTE address []? 301
DTE address []?

XTP config>add peer-router
Router's IP address? 128.185.100.1

XTP config>add remote-dte
Peer router's internal IP Address [0.0.0.0]? 128.185.100.1
DTE address []? 101
DTE address []?

*config

Config>set data-link x25 1
Config>set data-link ppp 2

Config>network 1
X.25 Config>set address 400
X.25 Config>set clocking external
X.25 Config>set speed 19200
X.25 Config>set equipment-type dte
X.25 Config>set svc low-inbound 0
X.25 Config>set svc high-inbound 0
X.25 Config>set svc low-outbound 0
X.25 Config>set svc high-outbound 0
X.25 Config>set svc low-two-way 1
X.25 Config>set svc high-two-way 64
X.25 Config>add protocol
	Protocol [IP]? xtp
	Window Size [2]? 
	Default Packet Size [128]? 
	Maximum Packet Size [256]? 
X.25 Config>exit

Config>protocol ip
IP config>add address
	Which net is this address for [0]? 2
	New address [0.0.0.0]? 128.185.100.9
	Address mask [255.255.0.0]? 255.255.255.0

IP config>set internal-ip-address
Internal IP address [0.0.0.0]? 128.185.100.3
IP Config>exit
Config>
Config>protocol xtp
XTP config>add local-dte
Interface number [0]? 1
DTE address []? 401
DTE address []? 402
DTE address []? 403
DTE address []? 404
DTE address []?		
XTP Config>add peer-router
	Router's IP address? 128.185.100.1
XTP config>add remote-dte
Peer router's internal IP Address [0.0.0.0]? 128.185.100.1
DTE address []? 201
DTE address []?
XTP config>exit
Config>

Not all parameters apply to all router platforms. Press Space twice after you type a command to display the available parameters for each command for your router. Enter help for information about using the command line interface.

[C] means the command is available at the XTP config> prompt.

[M] means the command is available at the XTP> prompt.

Table 24 XTP Commands

Command	Function
Add [C] [M]	Adds an interface, peer router, remote DTE or PVC definition.
Delete [C] [M]	Deletes an interface, peer router, remote DTE or PVC definition.
Disable-XTP [C]	De-activates the XTP forwarder.
Enable-XTP [C]	Activates the XTP forwarder.
Exit [C] [M]	Returns to the previous prompt.
List [C] [M]	Lists interfaces, peer routers, remote DTEs and PVC definitions.
Set [C]	Sets the keepalive timer.

Add [C] [M]

Syntax: add

local-dte

peer-router

remote-dte

pvc

If the interface is DCE, you can configure only one local X.25 node. If the interface is DTE, you can configure multiple local nodes.

Example: add local-dte

Interface number [0]? 1  
DTE address []? 101      
DTE address []?          

Example: add peer-router

Router's internal IP Address [0.0.0.0]? 128.185.100.2 

Example: add remote-dte

Peer router's internal IP Address [0.0.0.0]? 128.185.100.2
DTE address []? 301                                          
DTE address []?                                             

Three things need to exist in order to activate a PVC configuration:

• An X.25 PVC from the router to the local X.25 node.

• A TCP connection to the peer router where the remote node is resident.

• An X.25 PVC from the peer router to the remote X.25 node.

Local PVC Number [1]? 1
Local X.25 DTE address []? 100
Remote PVC Number [1]? 1
Remote X.25 DTE address []? 301

Syntax: delete

local-dte

peer-router

remote-dte

pvc

Example: delete local-dte

Interface number [0]? 1     
DTE address []? 101           
Record deleted

Example: delete peer-router

Router IP Address [0.0.0.0]? 128.185.100.2  
Record deleted

Example: delete remote-dte

DTE address []? 401

Example: delete pvc

Local DTE address []? 401
Remote DTE address []?
Record deleted 

Syntax: disable-xtp

Enable-XTP [C]

Syntax: enable-xtp

Exit [C] [M]

Syntax: exit

Config>   

List [C]

Syntax: list

all

xtp-status

local-dtes

peer-routers

remote-dtes

pvcs

keep-alive-timer

Example: list all

Local DTEs:
Interface        DTE Addr
   1             101
   2             201
                            
Peer Routers:
128.185.100.2
128.185.100.3
                                                                          
Remote DTEs:
DTE Address      Peer Router
    301         128.185.100.2
    401         128.185.100.3
    402         128.185.100.3
    403         128.185.100.3
    404         128.185.100.3
   
PVCs:
Local PVC      Local DTE      Remote PVC      Remote DTE
 Number          Address        Number          Address
  1                100              1             301

Example: list xtp-status

STATUS: XTP-ENABLED

Example: list peer-routers

Peer Routers:
128.185.100.2
128.185.100.3

Example: list remote-dtes

Remote DTEs:
DTE Address      Peer Router
    301         128.185.100.2
    401         128.185.100.3
    402         128.185.100.3
    403         128.185.100.3
    404         128.185.100.3

Example: list pvcs

PVCs:
Local PVC      Local DTE      Remote PVC      Remote DTE
 Number          Address        Number          Address
  1                100              1             301

Example: list keep-alive-timer

KEEP-ALIVE-TIMER: 10 seconds

Syntax: list

all

xtp-status

local-dtes

peer-routers

remote-dtes

pvcs

pvc-detailed

pvcs-all-detailed

pvcs-queues

svcs

svc-detailed

svcs-all-detailed

svcs-queues

Example: list all

LIST OF LOCAL DTES
------------------
Interface     Local
  No           DTE
  1            101
  2            201
                                                                           LIST OF PEER ROUTERS
--------------------
 Router             CNN   Number         Received              Sent
                   State  of  Ckts      Pkts     Bytes   Pkts     Bytes
128.185.100.3     ACTIVE     15           60      1533    12       142
128.185.100.2     ACTIVE     12           63      1620    10       130
                                                                         
LIST OF REMOTE DTES
-------------------
      Remote        Router
       DTE            IP
       404          128.185.100.3
       403          128.185.100.3
       402          128.185.100.3
       401          128.185.100.3
       301          128.185.100.2
                                                       
LIST OF PVCS                                     
------------                                     
Index     Int    PVC        Local       Remote      
 No        No   State        DTE          DTE       
 1         1     ACTIVE      100          301    
                                                 
LIST OF SVCS                                     
------------                                     
Index     Int    SVC        Local       Remote   
 No        No   State        DTE          DTE    
  1         1     ACTIVE     200          401   
  1         1     ACTIVE     200          402
  1         1     ACTIVE     200          403   
  1         1     ACTIVE     200          404

Example: list xtp-status

Status:  XTP-ENABLE

Example: list local-dtes

 LIST OF LOCAL DTES
------------------
Interface     Local
  No           DTE
  1            101
  2            201

Example: list peer-routers

LIST OF PEER ROUTERS                                                       
--------------------                                                       
Router             CNN   Number            Received          Sent
                   State  of  Ckts      Pkts     Bytes   Pkts     Bytes
128.185.100.3     ACTIVE     15           60      1533    12       142
128.185.100.2     ACTIVE     12           63      1620    10       130

Example: list remote-dtes

LIST OF REMOTE DTES                   
-------------------                   
     Remote        Router
       DTE            IP
       404          128.185.100.3
       403          128.185.100.3
       402          128.185.100.3
       401          128.185.100.3
       301          128.185.100.2

Example: list pvcs

LIST OF PVCS                                        
------------                                        
Index     Int    PVC        Local       Remote      
 No        No   State        DTE          DTE       
 1         1    ACTIVE       100          301    

Example: list pvc-detailed

PVC Index Number [1]? 1                                                   
                                                                          
PVC  1 IN DETAIL                                                          
----------------                                                          
Int    PVC         Received              Sent               Dropped       
 No   State      Pkts     Bytes      Pkts     Bytes      Pkts     Bytes   
 1     ACTIVE    55       3220       35        2350       15      1870

Example: list pvcs-all-detailed

                                                                             
LIST OF PVCS                                                                 
----------------                                                          
Int    PVC         Received              Sent               Dropped       
 No   State      Pkts     Bytes      Pkts     Bytes      Pkts     Bytes   
 1    ACTIVE     55       3220        35      2350        15      1870

Example: list pvcs-queues

Queue status of PVCs
--------------------
Index  Int    PVC          Hold Queue
 No    No     State           Count   
  1     1     ACTIVE           10

Example: list svcs

LIST OF SVCS                                     
------------                                     
Index     Int    SVC        Local       Remote   
 No        No   State        DTE          DTE    
  1         1     ACTIVE     200          401   
  1         1     ACTIVE     200          402
  1         1     ACTIVE     200          403   
  1         1     ACTIVE     200          404

Example: list svc-detailed

SVC Index Number [1]? 1
SVC  1 IN DETAIL                                                         
----------------                                                         
Int    SVC         Received            Sent            Dropped      
 No   State      Pkts     Bytes    Pkts     Bytes   Pkts     Bytes
 1	   ACTIVE      75       4220     55       3350    20       870

Example: list svcs-all-detailed

LIST OF SVCS                                                                
------------                                                                
Index     Int    SVC         Received        Sent          Dropped
No        No   State      Pkts    Bytes   Pkts    Bytes   Pkts    Bytes
1	   ACTIVE      75        4220       55        3350        20    870
1   ACTIVE      55        3220       40        2350        15     970
1   ACTIVE      63        4003       50        3892        13     111
1   ACTIVE      78        4967       58        4167        12     800

Example: list svcs-queues

Queue status of SVCs
--------------------
Index  Int    SVC          Hold Queue
 No    No     State           Count   

Syntax: set keep-alive-timer

Keep Alive Timer in seconds [10]?