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Forum Replies

  1. Dear Rene,

    Great stuff to read.
    Can you please bit more elaborate CSNP and PSNP with examples its good if you capture it in Wireshare as well.


  2. Hello Mohammad.

    Think about the CSNP as a packet that contains all of the LSPs from the current database. If this packet is sent to another router, the recipient will have a complete list of LSPs, in other words, it will have the sending router’s current view of the network. These packets are similar to OSPF database description packets.

    The PSNP is a partial list of LSPs. This is sent as a response to a specific request for specific information (for specific prefixes). This can be used to request an LSP (or LSPs) and also to acknowledge the recipt of an LS

    ... Continue reading in our forum

  3. Hello Mohammad Zaman

    CLNS is the OSI based service that provides connectionless network services, that is, connectivity between nodes. It essentially provides capabilities in an OSI network environment similar to those provided by IP and UDP together. UDP is mentioned here and not TCP because CLNS is strictly a best-effort service. CLNP is the actual protocol that is used to implement it.

    ISO (the governing body that defines these standards) makes a distiction between the service offered to higher layers (CLNS) and the protocol used to implement it (CLNP).

    ... Continue reading in our forum

  4. Hi Laz,

    Thanks for this informative feedback.
    Intermediate system ( Level 1 or Level 2 ) generate only one LSP per level and that LSP contain all prefixes that ISIS is originating.
    -If one LSP is carrying all prefixes,how CSNP comes into play.
    -Is PSNP behaviour is same for Broadcast and Point to Point network types.

    Mohammed Waqar

  5. @hussien.samer Ah yes now I see what you are getting at…

    It’s probably a design choice. Maybe the reserved a byte in case they wanted to go above the two decimal limit. I searched through some RFCs if I could find anything that explains it but there isn’t.

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