49.1.5 Packets

When a trace line describes a packet, the event type may be + (enqueue), - (dequeue), r (receive), d (drop), or h (hop).

type -t time -e extent -s source id -d destination id -c conv -i id

type is one of:

Hop: The packet started to be transmitted on the link from <source id> to <destination id> and is forwarded to the next hop.

Receive: The packet finished transmission and started to be received at the destination.

Drop: The packet was dropped from the queue or link from <source id> to <destination id>. Drop here doesn't distinguish between dropping from queue or link. This is decided by the drop time.

Enter queue: The packet entered the queue from <source id> to <destination id>.

Leave queue: The packet left the queue from <source id> to <destination id>.

The other flags have the following meaning:

-t <time>
is the time the event occurred.
-s <source id>
is the originating node.
-d <destination id>
is the destination node.
-p <pkt-type>
is the descriptive name of the type of packet seen. See section 26.5 for the different types of packets supported in ns.
-e <extent>
is the size (in bytes) of the packet.
-c <conv>
is the conversation id or flow-id of that session.
-i <id>
is the packet id in the conversation.
-a <attr>
is the packet attribute, which is currently used as color id.
-x <src-na.pa> <dst-sa.na> <seq> <flags> <sname>
is taken from ns-traces and it gives the source and destination node and port addresses, sequence number, flags (if any) and the type of message. For example -x {0.1 -2147483648.0 -1 ---- SRM_SESS} denotes an SRM message being sent from node 0 (port 1).

Additional flags may be added for some protocols.

-P <packet type>
gives an ASCII string specifying a comma separated list of packet types. Some values are:
A tcp data packet.
Generic acknowledgement.
Generic negative acknowledgement.
SRM data packet.

-n <sequence number>
gives the packet sequence number.

Tom Henderson 2011-11-05