Routing

what does loose and strict mean

Hi,

Please check the following link.

http://www.juniper.net/techpubs/en_US/junos9.6/information-products/topic-collections/nog-mpls-frr/primary-path-setting-up.html

■Strict—The route taken from the previous router to this router is a direct path and cannot include any other routers. This is the default. If the address is an interface address, this router also ensures that the incoming interface is the one specified. Specifying the incoming interface is important when there are parallel links between the previous router and this router, and because it ensures that routing can be enforced on a per-link basis.
For strict addresses, you must ensure that the router immediately preceding the router you are configuring has a direct connection to that router. The address can be a loopback interface address, in which case the incoming interface is not checked.

■Loose—The route taken from the previous router to this router need not be a direct path, can include other routers, and can be received on any interface. The address can be any interface address or the address of the loopback interface.

When a loose hop is configured, it identifies one or more transit LSRs through which the LSP must be routed.
The network IGP determines the exact route from the inbound router to the first loose hop, or from one loose hop to the next.
The loose hop specifies only that a particular LSR be included in the LSP.

When a strict hop is configured, it identifies an exact path through which the LSP must be routed.
Strict-hop EROs specify the exact order of the routers through which the RSVP messages are sent.

Regards,

Moses N

Hi,Mose Strict—The route taken from the previous router to this router is a dt irect path and cannot include any other routers. what does this mean in my case? the route from the previous router to this router...... what are these routers and route?

so

    192.168.13.3

     192.168.34.4

is wrong,right? becuase 192.168.34.4 is not a direct path to this r1

Hi,

If you are talking about the strict hop LSP r1-r3-r4,

first you need to specify r3's incoming interface IP address or loopback IP. Previous router is r1 and this router is r3, so this should be directly connected.

Then r4's incoming interface IP address or loopback IP. Here previous router is r3 and this router is r4 and these are directly connected.

Therefore strict hop path below is correct for LSP r1-r3-r4

192.168.13.3 strict

192.168.34.4 strict

Regards,

Moses N