ch 11 in network +

[treshombres]

Mr. Lammle,

Thank you for answering my other questions. I had some more questions. My first question was in regards to STP convergence. Why does it make it faster for switches to converge when you put them in hierarchical structure. Is it because if the core switch gets converged first it can quickly update the others? My next question was, when you say that each port on a router terminates a broadcast domain you mean enterprise routers that regurlaly break up subnets not soho routers that people use at home? Soho router generally each port on same subnet..? My nex question was you say in your example in book figure 11.9 that unicast packet is passed so that is fowarded by switches. wouldnt regular brodcast and multicast being passed as well since switches do not break up broadcast domains..?
I know i asked alot of questions :D. Whatever you can do to help me out much appreciated

Moyne

[Fuzz]

STP convergence is fastest when there is a proper structure. This is due to the fact that only the root bridge sends configuration BPDUs. When a topology change is discovered by a switch, it sends a TCN upstream to the root bridge, which then sends it to all other switches in the domain. If the root bridge is placed poorly, some switches could take much longer to update than others, which could lead to problems about which port is in which state, which CAM table entries are correct etc.

All routers break up broadcast domains, there is no distinction between large enterprise routers and smaller SOHO routers in this respect. You may be confusing routing with switching, as SOHO routers generally encorporate a 4 or 8 port switch on the LAN side. These are on the same subnet. Routing occurs between the LAN and WAN sides, which are on separate networks.

Broadcast and multicast traffic is replicated to all ports on a layer 2 switch, yes.

[treshombres]

Hey I really appreciate it. I might be missing the obvious but what is TCN. (topology change....ect..) Also, I think your right i was confusing switching with lan and wan side routing. the lan ports bascially act like 4 or 8 port switch on soho router. I think what confused me is that on enterprise level router (its my understanding) that every port is differnet subnet?

[Agnel]

Hey I really appreciate it. I might be missing the obvious but what is TCN. (topology change....ect..) Also, I think your right i was confusing switching with lan and wan side routing. the lan ports bascially act like 4 or 8 port switch on soho router. I think what confused me is that on enterprise level router (its my understanding) that every port is differnet subnet?

Every interface on the router SHOULD be on different subnets. The router wouldn't let you configure interfaces with the IP addresses from the same subnet.

Have you tried to use any simulators and have you configured the interfaces yet?

[Fuzz]

Hey I really appreciate it. I might be missing the obvious but what is TCN. (topology change....ect..) Also, I think your right i was confusing switching with lan and wan side routing. the lan ports bascially act like 4 or 8 port switch on soho router. I think what confused me is that on enterprise level router (its my understanding) that every port is differnet subnet?

A TCN (topology change notification) is a flag set in the BPDU to notify the root bridge that the toplogy has altered. It doesn't say how it has altered, only that a change has occured.

Every layer 3 port on a router will be in a different subnet, but be careful when you see switch modules on routers as they can operate in layer 2 mode.

[solnsusie]

hi,
just a quick question, what is the numbers on the switches in FIgure 11.11?

[sfhdweb]

Thanks everybody for sharing great info.