Cisco Systems BC-109 manual SR/TLB with Access Filtering Example, Example of a Bit-Swapped Address

SR/TLB with Access Filtering Example

Once you have determined the ring number and the bridge number, you can add the source-bridge transparent command to the file, including these two values as parameters for the command. The following partial configuration includes this source-bridge transparent entry:

!

source-bridge ring-group 10 source-bridge transparent 10 3 1 1

!

interface tokenring 0 source-bridge 1 1 10

!

interface tokenring 1 source-bridge 2 1 10

!

interface ethernet 0 bridge-group 1

!

interface ethernet 1 bridge-group 1

!

bridge 1 protocol dec

SR/TLB with Access Filtering Example

In the example shown in Figure 63, you want to connect only a single machine, Host E, on an

Ethernet to a single machine, Host R, on the Token Ring.

Figure 63 Example of a Bit-Swapped Address

Source-route

bridged domain

Token

Ring

Host R

MAC Addr:

0110.1234.5678

	Transparent
	bridging domain
Router	Host E
running SR/TLB	MAC Addr:
	0110.2222.3333
		S1110a

You want to allow only these two machines to communicate across the router. Therefore, you might create the following configuration to restrict the access. However, this configuration will not work, as explained in the paragraph following the sample configuration file.

Note For readability, the commands that control bridging are not shown here, just the commands that control the filtering.

interface tokenring 0 access-expression output smac(701)

!

interface ethernet 0

bridge-group 1 input-address-list 701

!

access-list 701 permit 0110.2222.3333

Configuring Source-Route Bridging BC-155