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Interpretation of Wireless Trace Format on NS-2

A few week ago, I was stuck with my perl script to do post-simulation using NS-2. I though I need to understand the trace format. After read the ns-Manual and some literature, so, here is interpretation of NS-2 trace format for wireless simulation.

  • To find the interpretation of all possible trace format when you do the
    wireless simulation, you’d better read the code of ns2 in file ns2home/trace/cmu-trace{.h, .cc}Mostly, the format would be as

    ACTION:	[s|r|D]: s -- sent, r -- received, D -- dropped
    WHEN:	the time when the action happened
    WHERE:	the node where the action happened
    LAYER:	AGT -- application,
    	RTR -- routing,
    	LL  -- link layer (ARP is done here)
    	IFQ -- outgoing packet queue (between link and mac layer)
    	MAC -- mac,
    	PHY -- physical
    SEQNO:	the sequence number of the packet
    TYPE:	the packet type
    		cbr -- CBR data stream packet
    		DSR -- DSR routing packet (control packet generated by routing)
    		RTS -- RTS packet generated by MAC 802.11
    		ARP -- link layer ARP packet
    SIZE:	the size of packet at current layer, when packet goes down, size increases, goes up size decreases
    [a b c d]:	a -- the packet duration in mac layer header
    		b -- the mac address of destination
    		c -- the mac address of source
    		d -- the mac type of the packet body
    [......]:	[
    		source node ip : port_number
    		destination node ip (-1 means broadcast) : port_number
    		ip header ttl
    		ip of next hop (0 means node 0 or broadcast)

    So we can interpret the below trace

    s 76.000000000 _98_ AGT  --- 1812 cbr 32 [0 0 0 0] ------- [98:0 0:0 32 0]


    Application 0 (port number) on node 98 sent a CBR packet whose ID is 1812 and size is 32 bytes, at time 76.0 second, to application 0 on node 0 with TTL is 32 hops. The next hop is not decided yet.

    And we can also interpret the below trace

    r 0.010176954 _9_ RTR  --- 1 gpsr 29 [0 ffffffff 8 800] ------- [8:255 -1:255 32 0]

    in the same way, as

    The routing agent on node 9 received a GPSR broadcast (mac address 0xff, and ip address is -1, either of them means broadcast) routing packet
    whose ID is 1 and size is 19 bytes, at time 0.010176954 second, from node 8 (both mac and ip addresses are 8), port 255 (routing agent).

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