Does ISIS Route-Leak help inter-level MPLS Tunnel?

[sshang2]

Hi,

I read some posts in the forum. Sounds like the well-known issue of inter-level MPLS LSP can be resolved by ISIS route leak (advertise level-2 route into level-1). Is it true? Is there related white paper or document?

Thanks!

Shixiong

[Harold Ritter]

Shixiong

It is indeed a know fact and you can find a reference to it in many documents discussing the need fot route leaking. Here's one of them:

http://www.cisco.com/en/US/partner/tech/tk365/tk381/technologies_tech_note09186a0080093f39.shtml

Hope this helps,

[Harold Ritter]

Shixiong,

I think I misread your question. As far as I know Inter-level MPLS TE Tunnel are stil a work in progress.

[Harold Ritter]

When I say work in progress I mean that it is possible today to do inter-level TE tunnel but not using a dynamic path-option since the information needed to run the CSPF is level specific.

Hope I'm making more sense now ;o)

[mazhar71]

Hi,

I would like to make some additions to the answers given.

You know L1 areas don't see the L2 routes and the routes of other L1 areas. L1 areas are like totally stub areas in OSPF. An LSP to be established, there should be a label in the cef table in Cisco and L1 routers don't see other routes in different areas. So there would not be a route so the label. Due to that reason there will not be a LSP to the destination. But route leakaging overcomes this issue. You can send L2 routes into L1 area. So you can see this route and produce a label for this route. In this way you can build LSP to that destination. This is normal LSP establishment.

But traffic engineering requires total view of the tophology and this is not possible because LSP databases of L1 areas and L2 area are different and there is some restrictions on Traffic engineering between areas but it is possible.

Regards

[sandhya123]

Hi Azhar,

Can you please let me know any traffic genertor which generates TCP UDP and IP packets and also where we can configure the Packet before generating the packets..For example I want to cnfigure the content of the packet..Other requirements are I want to give Source IP address and Source port Number along with Destination IP address and Destination port number..

Regards,

Sandhya