[Xorp-hackers] ospf topology

[Bruce M Simpson]

Selçuk Cevher wrote:
> Hi All,
>  
> I am trying to figure out how ospf process in xorp creates the 
> underlying topology information to be used for calculating the 
> shortest paths.
>  
> Is there a better way (documentation,etc.) than right jumping into the 
> source code of ospf that you can suggest me to follow ?

Look for where the Spt meta-class is instantiated and work your way back 
from that.

It is really quite simple when you pull off the trick of visualizing it. 
OLSR follows a similar process, however OSPF has hierarchical routing in 
the form of areas, so one instance of Dijkstra's algorithm runs for each 
Area.

If you look at the code which adds nodes and edges to the SPT you'll see 
where OSPF is getting the information from.

cheers
BMS