Re: IE Workbook lab 3 Task 2.1 and 4.1

Hello Julio!

Without the task in front of me, I am going to guess that R4 and R5 are PE routers in an MPLS L3 VPN scenario. To quote a "Deep Dive" from the very latest version of our WB II....

"The use of a /32 prefix allows the local router to advertise a NULL label for the prefix. Any non-host route will generate a special label that the local router will use to perform an aggregate lookup based on the destination IP address in the packet. With the NULL label advertisement, the label lookup will be performed based on the VPNv4 label, in the case of an MPLS VPN scenario."

Warmest Regards,

Anthony J. Sequeira, CCIE #15626
Senior CCIE Instructor

Test your Tier 1 Knowledge
Q: For RIPng, you can only disable split-horizon ...
A: globally
More Info: http://www.ietf.org/rfc/rfc2080.txt

On Jun 14, 2010, at 10:19 AM, Julio Carrasco wrote:

> Hello experts,
> I am reviewing this lab, and I saw, that on Task 2.1 it says that is necessay
> for Lo0 on R4 and R5, to be announced with a mask of 32 bits, so the LDP
> peering on task 4.1 needs both loopbacks to be a /32 mask.
> I do not understand exactly why, so could anyone please help me with that ?
>
> Thanks in advance and best regards !!!!
>
>
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Received on Tue Jun 15 2010 - 00:07:59 ART