The BRITE Output Format

A BRITE-formatted output file contains three sections:

1. Model information: information about the topology contained in the file. Includes number of nodes and edges, and information specific to the model used to generate the topology.
2. Nodes: for each node in the graph, a line is written into the output file with the following format :

   
   

   $$\mbox{{\bf NodeId xpos ypos indegree outgdegree ASid type}}$$
   
   

   The meaning of each field is described in Table 5.

   
   

   Table 5: BRITE Output format: Nodes section

   Field	Meaning
   NodeId	Unique id for each node
   xpos	x-axis coordinate in the plane
   ypos	y-axis coordinate in the plane
   indegree	Indegree of the node
   outdegree	Outdegree of the node
   ASid	id of the AS this node belongs to (if hierarchical)
   type	Type assigned to the node (e.g. router, AS)

   
   

3. Edges: for each edge in the graph, a line with the following format is written in the output file:

   
   

   $$\mbox{{\bf EdgeId from to length delay bandwidth ASfrom ASto type}}$$
   
   

   The meaning of each field is described in Table 6

   
   

   Table 6: BRITE Output format: Edges section

   Field	Meaning
   EdgeId	Unique id for each edge
   from	node id of source
   to	node id of destination
   length	Euclidean length
   delay	propagation delay
   bandwidth	bandwidth (assigned by AssignBW method)
   ASfrom	if hierarchical topology, AS id of source node
   ASto	if hierarchical topology, AS id of destination node
   type	Type assigned to the edge by classification routine

   
   

As an example, the output file shown in Listing 4.3 corresponds to a Waxman topology of 5 nodes and 8 edges, which was generated using the model RouterWaxman (Model number 1). Since it is a flat router-level topology, nodes do not have a corresponding AS id and therefore the ASid field contains $-1$. For the same reason, the ASfrom and ASto fields for the edges contain $-1$ values. The final field for both nodes and edges, correspond to a type assigned to them by a classification routine. BRITE provides a classification routine based on a classification method proposed in [3]. The classification routine is not called by default and hence both nodes and edges are unclassified (NONE type).