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<p>----- Original message ----- <br>
> Now, I have a question about the refresh message mentioned in the paper "A Case
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> for End System Multicast" ------ what is the content of the message? only the <br>
> sequence number or the list of entry that represent the group membership or both
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> ? <br>
> <br>
> Several places in the paper metioning the notion "refresh message" which I'm <br>
> confused of are: 1) paragraph two of section III-A : "To handle this, we require
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> that each member periodically generate a refresh message with monotonically <br>
> increasing sequence number, which is disseminated along the mesh." ------ I <br>
> think it refer to a message containing only sequence number here 2) figure 3. <br>
> and its description: "Actions taken by a member i on receiving a refresh message
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> from member j." ------ I think it refer to a message containing a list <br>
> representing the group member ship here. Seems contradictory in these places, so
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> what does "refresh message" really mean? <br>
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It's not contradictory. The paragraph in S.III-A simply doesn't describe the full contents of a packet.
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- Every group member periodically generates a message containing it's identity (IP address, perhaps), and a counter.
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- Each peer periodically sends a list of origin:counter pairs to its neighbours. <br>
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It doesn't take much of a leap for each peer to issue one message regularly which satisfies the algorithm.
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Remember that although the mesh is not fully connected, each peer maintains state referring to all other group members. So while refresh messages are exchanged between /neighbours/, the messages may contain information about the whole group.
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> by the way, does any one have an implementation of narada? <br>
<br>
I couldn't find any when I looked a few years ago. Though I did work on a link-state variant of Narada, called Orta, and you should still be able to pull the source code for that from here:
<a href="http://svn.sdstrowes.co.uk/">http://svn.sdstrowes.co.uk/</a> <br>
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Cheers, <br>
-S.<br>
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