Hi;

I'm not sure if I'm reading this correctly, but on pages 308-309 of the Sybex book, Lammle states that VLAN trunk lines require either fast ethernet or gigabit point to point links to be connected. Therefore, you cannot use 10 Mbps lines. However, when routing between VLANs, you can use either a 10BaseT or a FastEthernet connection. Why can you use a 10BaseT connection between routers to route VLANs, but not during point to point connections?

Tks

JerryL

[This message has been edited by JerryL (edited 01-07-2001).]

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I struggled through some of this recently. Here's what I have found:

1) The "Fast Ethernet or better to trunk" rule applies to ISL only, not to 802.1q or 802.10.

2) To do VLAN routing over an ISL trunk line (so that the router only needs 1 physical connection -- the "Router on a stick" idea), you need fast ethernet or better.

3) If your router(s) has only 10BaseT, you can still route VLAN's by connecting multiple router interfaces to the switch(es), 1 interface per VLAN. This is not trunking, of course, but it IS VLAN routing.

Remember that VLAN trunking and VLAN routing are 2 rather different things.

HTH,
doctorcisco

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Silicon is made from sand; nothing made from sand is allowed to wreck my day!

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Hi Doc;

Tks for replying. I guess I'm joining trunking and routing together. When reading them, they sounded related. I'll have to remember to try to keep them seperate.

I have a rough idea of the router on a stick concept. Between this book and Odom's book, I should be able to get a firmer grasp on the idea.

Tks

JerryL

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