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dst_portaddr,seqno,flags,sname);A nam trace file has a basic format to it. Each line is a nam event. The first character on the line defines the type of event andis followed by several flags to set options on that event. Each event is terminated by a newline character. -t ...Depending on the event type, there are different flags following the time flag.There are 2 sections in that file, static intial configuration events and animation events. All events with -t * in them areconfiguration events and should be at the beginning of the file. One thing to note is that nam can also be fed the trace file froma stream which enables it to be used with realtime applications. See the section Using Streams with Realtime Applicationsfor more information.Following we describe nam trace file format for different classes events and animation objects.46.1.1 Initialization EventsThe first section of a trace file must contain initialization information. All initialization events will have the flag -t *. Thistells nam that this event needs to be parsed before any animation has started.Version The following line define the nam version as required to visualize the given trace:V -t -v -a Normally there is only one version string in a given tracefile, and it is usually the first line of the file. An example is thefollowing:V -t * -v 1.0a5 -a 0The flag -v 1.0a5 tells nam that this script requires a version of nam > 1.0a5. For more information on this eventlook at the file tcl/stats.tcl under the procedure nam_analysis.Wireless If you want to use wireless nodes in nam you need the wireless intialization event.W -t * -x 600 -y 600This gives nam the size of the layout for the wireless world. The -x value is the width and -y is height. For moreinformation look at the file animator.tcl in the procedure infer-network-model.Hierarchy Hierarchical address information is defined by:A -t -n -o -c -a -h -m -s This trace gives the details of hierarchy, if hierarchical addressing is being used for simulation. Flag -n indicate the total number of hierarchical tiers, which is 1 for flat addressing, 2 for a 2-level hierarchy etc. Flag -o denotes the total number of bits used for addressing. Flag -h specifiesthe level of the address hierarchy. Flag -m and -s describes the address mask and the bit shiftof a given level in the address hierarchy, respectively. Here is an example of a trace for topology with 3 level hierachy:396