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Re: [ns] node address and MAC address
What do you mean by "previous hop"? On an Ethernet segment there can't be more
that one "hop" : from source address to destination address. So you probably
want the source address.
Exception with the LanNode : the LAN itself is a virtual-Node so packets look
like they are travelling from src to LAN to dst.
>Date: Wed, 26 Jul 2000 14:29:13 -0700 (PDT)
>From: Yan Yu <[email protected]>
>To: ns-users <[email protected]>
>Subject: [ns] node address and MAC address
>MIME-Version: 1.0
>
>
>My problem is to implement a reliable link layer. IN order to send a
>hop-by-hop link layer ack back to the previous hop, I reverse the MacSA
>and MacDA in the packet, and send it back. But this is not enough for
>link layer. By reversing the macSA and macDA, the packet can reach the mac
>layer of the previous node, it can NOT reach the link layer of the
>previous
>node. I guess there is some kind of filter which will filter out any
>packets whose dst address is diffrent from myself. So I change the dst
>address in packet to the MAC address of the previous node (i do not know
>how to get the node address of previous hop node), It works when the node
>address and MAC address of the nodes are the same. However, The packet
>won't be able to get to the link layer if the Mac address happen to be
>different from the node address..
>In order to get around this,
> my question is:
>1. How to get to know the node address of the previous hop node?
>( I use wired LAN..)
>or how to get the node address from its MAC address?
>
>2. if I can not get the above information, can I change the node address
>arbitrarily, so that the node address can be the same as the MAC address?
>If I write up such a function myself to change node address, will the
>change mess up the normal operation in ns, such as routing?
>
>THanks a LOT for any feedback in advance!
>yan
>
>
>
Tarik