Hi Ben, Thanks for the reply. I am not very aware of the Linux implementation you have but am eager to find out (or even help enhance). I have seen one other Linux implementation of a VLAN in the past. I have a few points to ask: - > Bridging between MAC-VLAN interfaces does not make sense to me, so I think > this probably doesn't work in any useful manner. 1. I am not sure of how the implementation is but Mac-Based VLAN should only be used to resolve a VLAN based on source Mac-Address when the packet comes in untagged. Once the VLAN is resolved the bridging functionality is done the same way as for any other VLAN bridging send packet only on port that is part of the VLAN. Mac-Based VLAN is necessary in conditions where client can roam and hence the port on which the packet from a client arrives is not fixed. We can have a Mac-Based VLAN database for the same, and in this condition a Mac-based VLAN is necessary. 2. > The Linux MAC-VLAN stuff is not in the official kernel, but I have > done fairly extensive testing on the mode that matches on the > destination MAC. I am not sure of what you mean by Mac-destination based VLAN? Do you in case the packet is a multicast or a broadcast packet send the packet to all the addresses on the VLAN? 3. > Port-based VLANs mean nothing unless you are bridging, and Linux > already supports bridging regular ethernet interfaces and 802.1Q VLANs, > so this is supported as well. Could you explain this further, I am a bit confused? Thanks, Vishwas -----Original Message----- From: vlan-bounces@xxxxxxxxxxxxxxx [mailto:vlan-bounces@xxxxxxxxxxxxxxx] On Behalf Of Ben Greear Sent: Tuesday, September 28, 2004 12:53 AM To: Linux 802.1Q VLAN Subject: Re: [VLAN] vlan & osi-model Vishwas Manral wrote: > Hi Lars, > > Hmmm....let me explain then.;-) The way a switch can assign VLAN's is upto the administrator's discretion (we can as well have it based on a particular application - layer-7 or any other criteria). However VLAN is a layer-2 thing. Maybe someone else too can join in? > > A port based VLAN means that in case a packet comes in untagged the VLAN assigned to the packet in a VLAN aware switch is that of the default VLAN Id of the port. In a Mac-based VLAN certain Mac Addresses are assigned to the same Vlan. As far as I know we have support for Mac-Based VLAN in Linux, though I know some flavors do support Port-Based too. > > Thanks, > Vishwas The Linux MAC-VLAN stuff is not in the official kernel, but I have done fairly extensive testing on the mode that matches on the destination MAC. I have not tested the mode that matches on the source MAC but it worked at one time, at least. Port-based VLANs mean nothing unless you are bridging, and Linux already supports bridging regular ethernet interfaces and 802.1Q VLANs, so this is supported as well. Bridging between MAC-VLAN interfaces does not make sense to me, so I think this probably doesn't work in any useful manner. Ben -- Ben Greear <greearb@xxxxxxxxxxxxxxx> Candela Technologies Inc http://www.candelatech.com
