13 August 2011

Manual tracing–tracefile

Assume you created a tcl file for a wireless simulation and it generates a trace file (usually .tr as extension). If any tracing softwares are not available, how to interpret manually, here is the step
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

flags:

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

flags:

[......]: [  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 0.0297823400 _1_ RTR --- 2012 cbr 32 [0 0 0 0] ------- [1:0 0:0 32 0]


as Application 0 (port number) on node 1 sent a CBR packet whose ID is 2012 and size is 32 bytes, at time 0.029 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).