Hi Ben, all, Most switches and routers I work with (that have q-in-q capability) tend to have a configurable ethertype for a second (or outer) vlan tag. Look at http://www.google.com/search?q=ethertype+0x9100 to see what I mean. 0x9100 is starting to look like a more-or-less standard for metro ethernet providers. Vendors supporting this include Foundry, Cisco, HP and Juniper at the very least. A configurable ethertype for at least the outer vlan tag looks like something that we're going to need if there's going to be a claim that the vlan code supports what the big vendors have taken to call Q-in-Q. I myself, however, agree with you that sticking with a single ethertype and just keeping count yourself is the more elegant solution :-) Cheers, Remco -----Original Message----- From: vlan-bounces@xxxxxxxxxxxxxxx [mailto:vlan-bounces@xxxxxxxxxxxxxxx] On Behalf Of Ben Greear Sent: maandag 6 december 2004 18:21 To: Linux 802.1Q VLAN Subject: Re: [VLAN] vlan stacking Remco van Mook wrote: > > While I agree with Ben that it will probably 'just work', what would > be very nice is to be able for every layer of vlan tags to be able to > set the ethertype; while 0x8100 is default for 802.1p/q, there is no > standard for 'q in q'. Some switch vendors choose 0x9100, others let > you set a type in configuration. > > How about the following extra command in vconfig (with the > implementation in the kernel to match, of course :) > > set_ether_type <interface-name> <ethertype> > > Offloading vlan tags to a nic probably won't work using other > ethertypes, but otherwise implementation ought to be fairly simple. If the switch/router can deal with normal protocol stacking, then leaving it an 0x8100 is the correct answer. The 'original' protocol is found in the .1q header, and you can just check it to see if you are encapsulating .1q or some other ethernet protocol. This would allow arbitrary stacking, ie .1q inside of .1q inside of .1q inside of ethernet. This is how Linux works (or should work, as I have not tested this recently.) I do not want to special case .1q inside of .1q unless that becomes necessary to work with a significant portion of third-party equipment. Ben > > Cheers, > > Remco van Mook > Virtu > > -----Original Message----- > From: vlan-bounces@xxxxxxxxxxxxxxx > [mailto:vlan-bounces@xxxxxxxxxxxxxxx] On Behalf Of Ben Greear > Sent: Sunday, December 05, 2004 01:04 > To: hans.dengel@xxxxxxxxxxxxx; Linux 802.1Q VLAN > Subject: Re: [VLAN] vlan stacking > > Hans Dengel wrote: > >>Hi, >> >>maybe a typical newbie question: >>is there any implemantation on "q in q" or stacked vlans or vman? > > > I think it will just work in Linux...but I'm not aware of any other > stack that will support it. > > Ben > > -- > Ben Greear <greearb@xxxxxxxxxxxxxxx> > Candela Technologies Inc http://www.candelatech.com > > _______________________________________________ > Vlan mailing list > Vlan@xxxxxxxxxxxx > http://www.lanforge.com/mailman/listinfo/vlan > > _______________________________________________ > Vlan mailing list > Vlan@xxxxxxxxxxxx > http://www.lanforge.com/mailman/listinfo/vlan > -- Ben Greear <greearb@xxxxxxxxxxxxxxx> Candela Technologies Inc http://www.candelatech.com _______________________________________________ Vlan mailing list Vlan@xxxxxxxxxxxx http://www.lanforge.com/mailman/listinfo/vlan
