Subject: ER-Hop 3

From: [email-masked]
Date: 3 Apr 2001 21:12:33 -0700

Hi all,

I got some questions about ER-Hop 3.
in draft-ietf-mpls-cr-ldp-05.txt, it says:

<<<<<<<<<<<<<<<<<<<<<
   To determine the next hop for the path, a node performs the following steps: 
    
      1. The node receiving the Label Request Message must first evaluate the first ER-Hop. If the L bit is not set in the first ER-Hop and if the node is not part of the abstract node described by the first ER-Hop, it has received the message in error, and should return a "Bad Initial ER-Hop" error. If the L bit is set and the local node is not part of the abstract node described by the first ER-Hop, the node selects a next hop that is along the path to the abstract node described by the first ER-Hop. If there is no first ER-Hop, the message is also in error and the system should return a "Bad Explicit Routing TLV" error using a Notification Message sent upstream. 

Q1:
How to verify that a local node is not a part of the abstract node described by AS? 
Does it mean that the the AS number of local node is different from the AS number of
the abstract node?

Q2:
If
1) the first ER-Hop's L bit is set (i.e. loose ER-LSP);
2) and the local node is not a part of the abstract node described by the first ER-Hop;
3) the first ER-Hop is an AS number.
How to select a next hop that is along the path to the abstract described by an AS number?
Is it possible to query a route using an AS number as an input to the routing table? 
If yes, how to? by using routing socket?

Thanks in advance.

X.Q. Yan

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