North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: OSPF multi-level hierarchy: Necessary at all?
> > I was talking about ISP network which mostly is leased-line based. > It depends on link stability and router stability. As I pointed out > in my previous message, the more router and link a network has (i.e. > the large scaled network), the large chance of having link flapping > and router crashes (if you think in percentage sense), the more flooding, > SPF calculation and LSDB update all routers in the network have to > handle. If there is a hierarchy, then only a portion of routers (not all > the routers) would need to handle flooding, SPF calculation and LSDB update. You are 100% right - it's the classic. Through the initial question whas _does we need hierarchical multi-level SPF routing schema?_. And my opinion was _yes, but due to administration, but not CPU/memory issues (yes, this is important too but it's importance is usially overestimated). And no one from this list argued for this hierarchy at all. > > Also, the large the size of network (lots of routers and links), the > bigger the LSDB and the higher complexity of SPF calculation. > > --Jessica > > > Aleksei Roudnev, Network Operations Center, Relcom, Moscow (+7 095) 194-19-95 (Network Operations Center Hot Line),(+7 095) 230-41-41, N 13729 (pager) (+7 095) 196-72-12 (Support), (+7 095) 194-33-28 (Fax)
|