ISIS on IPRAN

How you can deploy ISIS on IPRAN ?

I will talk about two way that can help you to deploy ISIS on IPRAN , the first one if you have a small network that not containing a lot of routers , in this case you can make all the routers as Level 2 ISIS

the second one is to use hierarchical design , that means to have L1 routers , L2 routers and L1/2 Routers in your network.

now we will start the configuration :

isis 1

is-level level-2  // Change the ISIS level to L2 , By default its L1/2 

cost-style wide      // To enable the TLV that support the Traffic Engineering                                 

timer lsp-generation 1 50 50 level-2   //Set the interval for generating the same LSP fragment.

flash-flood 15 level-2         //Configure LSP fast flooding.

bfd all-interfaces enable   //Enable BFD for IS-IS to configure BFD for all IS-IS interfaces.

network-entity 22.0000.0000.0001.00

timer spf 1 50 50             //Set the interval for SPF calculation.

traffic-eng level-2            //Configure IS-IS extension to enable TE on the entire network.

#

interface GigabitEthernet1/0/0

undo shutdown

ip address 22.1.3.1 255.255.255.0

isis enable 1

isis bfd enable      //Enable BFD for IS-IS for a single interface.

interface GigabitEthernet1/0/1

undo shutdown

ip address 22.1.2.1 255.255.255.0

isis circuit-type p2p      //Change the type of a broadcast interface to P2P to avoid DIS election and thus speed up route convergence.

isis enable 1

isis bfd enable

Notes: The ISPF algorithm and RPC algorithm are the default algorithms of IS-IS and are enabled by default. Therefore, they do not need to be configured.

By the above configuration we configure the ISIS on the network , with some small changes for the Level if the router is in L1 or L1/2