9.3 Release Notes, Using NETBuilder Family Software

Place this section containing new information at the front of Chapter 46.

Switching can occur on either a switched virtual circuit (SVC) or a permanent virtual circuit (PVC).

When configured for a switched virtual circuit and switching occurs, a switched virtual circuit is established. The switched virtual circuit is disconnected automatically when communication is completed.

When you use X.25 PVC support for tunneling, the circuit stays up at all times when the associated underlying interfaces are in the up state. When the PVC is properly configured and the NETBuilder II is booted, or when the HSS or LAN state is bounced, the tunnel setup continuously attempts to connect the local end to the remote end until a tunnel circuit is established and running. The PVC tunnel is in the down state only when the HSS or LAN interface is in the down state.

When the XSWitch Service receives an incoming X.25 call, it looks in the X25Prefix table to find an entry whose X.25 address prefix matches the address of the called address. When a match is found, the associated HSS port is used for switching. These X.25-prefix-to-HSS-port entries are user-configurable.

Setting Up Local Switching on a PVC

This new section describes setting up local switching on a permanent virtual circuit.

Figure 46-1 is an example of using local switching on a PVC to forward an X.25 call from WAN #1 to WAN #2. This difference between local switching on an SVC and local switching on a PVC is the way in which the circuit is maintained.

Figure 46-1 Local Switching on a PVC

In local switching with PVCs, one router with two HSS ports is involved for each switched circuit. The configuration requires an XSWPVC to indicate an incoming PVD and the switched outgoing PVC mapping. As in global switching circuits, the local switching PVC circuit should stay up and running as long as the router is operating and both HSS ports are in the up state.

To configure local switching on a permanent virtual circuit, follow these steps:

1 . Configure the permanent virtual circuits by entering:

ADD !3 -X25 PVC 3,3 1122 FF 0

ADD !4 -X25 PVC 9,9 444444 FF 0

These commands create PVC connections on ports 3 and 4. The PVCs carry switched traffic as specified by the protocol ID FF to and from logical channel numbers 3 and 9 with DTE addresses 1122 and 444444.

Always use protocol identifier FF to indicated switched PVCs.

2 . To verify the X.25 PVC configuration, enter:

SHow -X25 PVC

A display similar to the following appears:

Port !3 PVC 3,3 1122 FF 0

Port !4 PVC 9.9 444444 FF 0

3 . Specify the tunnel by entering:

ADD !3 -XSWitch XSWPVC 1122 3 !4 444444 9

This command maps a circuit from port 3 with DTE address 1122 and logical channel number 3 into the target destination DTE address 444444 and logical channel number 9, which is port 4.

4 . To verify the configuration, enter:

SHow -XSWitch XSWPVC

A display similar to the following appears:

Port#/IPAddr	SDTE	SLCN	DESTPort/IPAddr	DDTE	DLCN
!3	1122	3	!4	444444	9

This display shows that a PVC from source port 3 with DTE address 1122 will be switched to destination port 4 with DTE address 444444 and local channel number 9.

5 . To verify that a locally switched X25 PVC is up and running enter:

SHOW -XSWitch SWitchedVC

A display similar to the following appears.

SW#	XSRC	SDST	SRC(LCN)	DST(LCN	STATE	BYTESXFER
0	1122	444444	3(4)	4(9)	ACT	01

1 Indicates X25 in the switch circuit.

Setting Up Global Switching on a PVC

This section describes how to configure global switching (X.25 tunneling over IP). Figure 46-2 shows an example of a bridge/router using tunneling to forward an X.25 call from WAN #1 to WAN #2 on a permanent virtual circuit.

Figure 46-2 Global Switching on a Permanent Virtual Circuit over a LAN

A tunnel is established between two NETBuilder bridge/routers with one bridge/router acting as the local end and the other acting as the remote end. Multiple circuits can be supported between two NETBuilder bridge/routers where each circuit is set up independently.

The local end (source) and remote end (destination) addresses can be an IP address or HSS port. For tunnel mapping, one address must be an HSS port and the other must be an IP address. When the local end (source) is an HSS port the and the remote end (destination) is an IP address, the circuit is called a local end of the tunnel. When the local end (source) is an IP address and the remote end is an HSS port, the tunnel is called a remote end tunnel. The NETBuilder II bridge/router can support both local end and remote end of the tunnels at the same time as long as each circuit is properly configured on both NETBuilder bridge/routers.

Configuring the Local-end Router

This example shows how to configure two PVC switch circuits in a tunnel. To configure global switching on a permanent virtual circuit, on the local end NETBuilder II bridge/router, follow these steps:

1 . To specify the permanent virtual circuit with a profile ID (FF) set to switching, enter:

ADD !3 -X25 PVC 2,2 1122 FF

ADD !3 -X25 PVC 5,5 1122 FF

These commands indicate that logical channel numbers 5 and 2 from port 3 with the DTE address 1122 will be switched.

2 . Verify that the PVC is properly configured by entering:

SHow -X25 PVC

A display similar to the following appears:

Port !3 PVC 5,5 1122 FF 0

Port !3 PVC 2,2 1122 FF 0

These two entries indicate that logical channel numbers 5 and 2 from port 3 with DTE address 1122 will be switched.

3 . To specify the tunnel, enter:

ADD !3 -XSWitch XSWPVC 1122 2 129.213.201.163 444444 4

ADD !3 -XSWitch XSWPVC 1122 5 129.213.201.163 444444 8

The first command maps a circuit from port 3, DTE #1122, logical channel number 2 into a remote end through the tunnel into 129.213.201.163 with a final destination of DTE#444444, logical channel number 4. The second command maps a circuit from port 3, DTE #1122, logical channel number 5 into a remote end through the tunnel into 129.213.201.163 with a final destination of DTE#444444, logical channel number 8.

4 . Verify that the tunnel is configured properly by entering:

SHow -XSWitch XSWPVC

A display similar to the following appears:

Port#/IPAddr	SDTE	SLCN	DESTPort/IPAddr	DDTE	DLCN
!3	1122	2	129.213.201.163	444444	4
!3	1122	5	129.213.201.163	444444	8

Entry number one maps a circuit from port 3 with DTE#1122 and logical channel number 2 into a remote tunnel with its final destination as DTE #444444 with logical channel number 4. Entry number two maps a circuit from port 3 with DTE address 1122 and logical channel number 5 to its final destination at DTE address 444444 with logical channel number 8.

To configure global switching on a permanent virtual circuit, on the remote end NETBuilder bridge/router, follow these steps:

1 . To specify the permanent virtual circuit with a profile ID (FF) set to switching, enter:

ADD !4 -X25 PVC 8,8 444444 FF

ADD !4 -X25 PVC 4,4 444444 FF

These commands indicate that logical channel numbers 8 and 4 from port 4 with the DTE address 444444 will be switched.

2 . Verify that the PVC is properly configured by entering:

SHow -X25 PVC

A display similar to the following appears:

Port !4 PVC 8,8 444444 FF 0

Port !4 PVC 4,4 444444 FF 0

These two entries indicate that logical channel numbers 8 and 4 from port 4 with DTE address 444444 will be switched.

3 . To specify the tunnel, enter:

ADD !129.213.201.162 -XSWitch XSWPVC 1122 2 !4 444444 4

ADD !129.213.201.162 -XSWitch XSWPVC 1122 5 !4 444444 8

The first command maps a circuit from IP address 129.213.201.162 with the DTE source DTE#1122, logical channel 2 into its destination through the HSS port 4 with local channel 4 and DTE address 444444. The second command maps a circuit from IP address 129.213.201.162 to the DTE#1122, logical channel number 5 into its destination through the HSS port 4 with local channel number 8 and DTE address 444444.

4 . Verify that the tunnel is configured properly by entering:

SHow -XSWitch XSWPVC

A display similar to the following should appear:

Port/IPAddr	SDTE	SLCN	DEST Port/IPAddr	DDTE	DLCN
129.21.201.162	1122	2	!4	444444	4
129.21.201.162	1122	5	!4	444444	8

Entry one shows that a tunnel is mapped from 129.213.201.162 with the DTE address of DTE#1122 and logical channel number 2 into its destination through the HSS port 4, with logical channel number 4 and DET address DTE#444444.

Entry two shows that a tunnel is mapped from 129.213.201.162 with the DTE address of 1122 and logical channel number 5 into its destination through the HSS port 4, with logical channel number 8 and DET address 444444.

5 . Verify that the tunnel X25 PVC is up and running by entering:

Show -XSWitch SWitchedVC

A display similar to the following appears:

SW#	XSRC	SDST	SRC(LCN)	DST (LCN)	STATE	BYTESXFER
0	1122	444444	129.213.201.162	!4(4)	ACT	01
1	1122	444444	129.231.201.162	!4(8)	ACT	0*

1 Indicates X25 in the switch circuit.

When correctly configured, the local and remote bridge/routers attempt to set up a tunnel between each other automatically. Automatic setup also occur swhen the port is bounced (port down and then back up again).

If this is the first configuration for the router, you may need to toggle the path and port to start the PVC tunnel setup sequence.

A typical error occurs when the two ends of the tunnel have a mismatch in the XSWPVC values. When a mismatch occurs, the tunnel will not set up properly. When the router detects this configuration error, it reports the following messages:

WARNING: A misconfiguration of PVC or XSWPVC!!!

Please: Correct the configuration and

DELete -XSWitch SWitchedVC ALL on both sides.

When this message is displayed, follow these recovery steps:

1 . Check your network diagram and verify that the configuration setup for PVC and XSWPVC are matched on both ends of the tunnel.

On both the local and the remote routers, enter:

SHow -X25 PVC

SHow -XSWitch XSWPVC

Correct the parameters as required.

2 . Bounce (toggle) the HSS port by disabling the path and then re-enabling the path.

3 . Verify that the setup is correct by entering:

SHow -XSWitch SwitchedVC

A display similar to the following appears:

SW#	XSRC	SDST	SRC (LCN)	DST (LCN)	STATE	BYTESXFER
0	1122	5555555	!3 (2)	10.11.12.14.	ACT	1681

1 Indicates and X25 PVC in the switch circuit.

The ACT state indicates that the tunnel is in active state.

The Bytesxfer field reports the number of data bytes traveling through this circuit.

This section describes how to configure global switching over WAN media. Figure 46-3 shows an example of a bridge/router using tunneling to forward multiple X.25 calls from WAN #1 to WAN #2, WAN #3 and WAN #4 on a permanent virtual circuit.

Figure 46-3 Global Switching on a PVC over a WAN

Figure 46-3 is an example of setting up NETBuilder II bridge/routers to use tunnelled PVCs to other routers. In this example, the HSS port used on each router is port 4. The user profile identifier 0 also is used. For each PVC, a fake DTE address is created to associate with the PVC to identify the local end and the remote end of the tunnel. 1111, 2222, 3333, and 4444 are fake IDs. One fake DTE address can associate may PVC. For example, 1111 in bridge/router associates with its local logical channel numbers 1, 2, and 3.

To configure bridge/router A, follow these steps:

1 . Configure -X25 PVC for logical channel numbers 1, 2, and 3 by entering:

ADD !4 -X25 PVC 1,1 1111 FF 0

ADD !4 -X25 PVC 2,2 1111 FF 0

ADD !4 -X25 PVC 3,3 1111 FF 0

These commands add permanent virtual circuits to HSS port 4 and associates logical channel number 1, 2 and 3 with the fake DTE address 1111, indicates Switching with protocol identifier FF, and establishes the user profile IS as 0.

2 . Configure the -XSWitch XSWPVC parameter for logical channel numbers 1, 2, and 3 by entering:

ADD !4 -XSWitch XSWPVC 1111 1 128.102.100.100 2222 1

ADD !4 -XSWitch XSWPVC 1111 2 128.102.100.101 3333 1

ADD !4 -XSWitch XSWPVC 1111 3 128.102.100.103 4444 1

The first command establishes a tunnel with bridge/router B in the example configuration. The incoming HSS port is port 4. 1111 is the associated fake DTE address, the first 1 is the logical channel 1 on the source side, 128.102.100.100 is the target tunnel IP address (router B), 2222 is the target fake DTE address, and the final 1 is the logical channel number 1 at the target end (router B.)

The second and third commands establish similar settings for the other two routers in the example configuration.

The target ends of the tunnels need to be configured on the remote routers.

Configuring Remote Router B

To configure remote bridge/router B, follow these steps:

1 . Configure the -X25 PVC by entering:

ADD !4 -X25 PVC 1,1 2222 FF 0

This command specifies port 4 as the HSS port, 1,1 indicates the pvc_range which is logical channel number 1 on the router B side, 2222 is the fake DTE address, FF is the protocol identifier indicating switching, and 0 is the user profile identifier.

2 . Configure the -XSWitch service XSWPVC parameter by entering:

Add !128.102.100.102 -XSWitch XSWPVC 1111 1 !4 2222 1

This command establishes 128.102.100.102 as the incoming tunnel address, which is router A. 1111 is the source DTE address, which is router A, The first 1 indicates the logical channel number 1 on router A. The HSS port 4 is the outgoing HSS port on router B. 2222 is the fake DTE address and the last 1 is the destination logical channel number on router B.

To configure router C, follow these steps:

1 . Configure the -X25 PVC by entering:

ADD !4 -X25 PVC 1,1 3333 FF 0

This command specifies port 4 as the HSS port, 1,1 indicates the PVC range, which is logical channel number 1 on the router C side, 3333 is the fake DTE address, FF is the protocol identifier indicating switching, and 0 is the user profile identifier.

2 . Configure the -XSWitch XSWPVC parameter by entering:

Add !128.102.100.102 -XSWitch XSWPVC 1111 2 !4 2222 1

This command establishes 128.102.100.102 as the incoming tunnel address, which is router A. 1111 is the source DTE address, which is router A. The 2 indicates the logical channel number 2 on router A. The HSS port 4 is the outgoing HSS port on router C. 3333 is the fake DTE address and the last 1 is the destination logical channel number on router C.

To configure router D, follow these steps:

1 . Configure the -X25 PVC parameter by entering:

ADD !4 -X25 PVC 1,1 4444 FF 0

This command specifies port 4 as the HSS port, 1,1 indicates the pvc_range which is logical channel number 1 on the router D side. 4444 is the fake DTE address, FF is the protocol identifier indicating switching, and 0 is the user profile identifier.

2 . Configure the -XSWitch XSWPVC parameter by entering:

Add !128.102.100.102 -XSWitch XSWPVC 1111 3 !4 4444 1

This command establishes 128.102.100.102 as the incoming tunnel address, which is router A. 1111 is the source DTE address which is router A. The 3 indicates the logical channel number 3 on router A. The HSS port 4 means the outgoing HSS port on router D. 4444 is the fake DTE address and the last 1 is the destination logical channel number on router D.

You may need to adjust several parameters based on how your network is configured. You may need to configure X.25, Level 2, and Level 3 parameters to match the values in the entered in this procedures. Refer to the values for the parameters in the PATH Service, the LAPB Service, the X25 Service, the PORT Service, and the PROFILE Service.

The following terms are used in this chapter to explain switching:

tunneling service	A method of connecting peer iIternets that are not physically reachable with the X.25 Protocol. This is a generic service on NETBuilder II bridge/routers. Global switching interfaces with it to set up and maintain the tunnel between two entities over the Internet.
encapsulation	Conveying an X.25 packet within a TCP data packet so it can be forwarded through a TCP connection.
decapsulation	Extracting an X.25 packet encapsulated in a TCP data packet for forwarding through a locally attached X.25 WAN.
Local end tunnel	For tunnel mapping, one address must be an HSS port and the other must be an IP address. When the local- nd (source) is an HSS port the and the remote end (destination) is an IP address, the circuit is called a local end tunnel.
Remote-end tunnel	When the local end (source) is an IP address and the remote end is an HSS port, the tunnel is called a remote end tunnel.