""Stephen Hoover"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > ------------------------- > > > actually it is by doing secondaries, but i would highly recommend doing > > > vlans if possible. keep it clean and simple. > > > > > > one may also configure the physical interfaces as L3 interfaces - just as > > one might do on a router with several ethernet ports. > > > Oooooo ok, now THAT statement leads me to believe the L3 switching IS > possible without VLANs. >
forgive the rant. you are not to blame. all the marketing hype is to blame. forget OSI. For L-anything. for data ( packets, frames, whatever ) to get from here to there, somethng has to happen. if I have a 75xx router with 300 ethernet ports, and I bridge all those ports, do I have an L3 switch, or a router? for data to get from here to there, it must be forwarded. I know Howard is going to jump all over my fast and loose use of the term "forward" but that is what happens. If my PC wants to send data to your PC, that data is forwarded to your PC. If your PC and mine are on the same subnet / hub / switch / vlan, it is L2 forwarding ( switching ). If the devices are on different subnets / switches . vlans / hubs then the packets are L3 forwarded ( routed ) As Priscilla has been pointing out, the issue is one of how networks work, how packets are forwarded, how data gets from here to there. An L3 device is a router is able to forward packets based on an L3 address, whether that L3 address be appletalk, IPX, or IP. an L2 device is a switch is a bridge is able to forward packets based on L2 addreses i.e. MAC address. the fact that some equipment can function as both a switch and a router ( anyone remember "brouters"? ) is irrelevant. on a 3550, a physical port ( into which you plug the ethernet patch cable ) can be stand alone physical, can be part of a vlan, thus making it distinct from ports on the same box that are not in the same vlan, or can have an IP ( L3 ) address. an SVI ( switch virtual interface ), invoked by the command "interface vlan x", is a representation of a group of ports that have been placed into a single vlan. The SVI represents those ports to the routing funtion, and behaves no differently that a router's ethernet port plugged into a hub. I'm hoping this helps clarify the concept. I believe you have been confused by the study materials you are reading, and by the mis-information that has been presented here on the list. sorry to have not taken the time to be more thorough in earlier replies. you can never go wrong studying Priscilla's posts, either. hope this is starting to make sense to you . Chuck > > -Stephen Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=63206&t=63147 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
