Hi Colin: I think you're describing the draft. Basically the edge router does proxy-ND over the backbone. So if a node on the backbone looks up a 6LoWPAN device, the edge router answers NS with NA on behalf of the device. So the node sends packets via the edge router. The edge router forwards back to the device over the lowpan. As you figures, this is why the device needs to periodically maintain the binding with the edge router.
This is somewhat similar to mobile IPv6 though there's no tunnel. Pascal >-----Original Message----- >From: Colin O'Flynn [mailto:[email protected]] >Sent: mardi 17 novembre 2009 17:55 >To: 'Carsten Bormann'; 'Alexandru Petrescu' >Cc: Pascal Thubert (pthubert); Ralph Droms (rdroms); '6lowpan' >Subject: RE: [6lowpan] Thoughts on draft-ietf-6lowpan-nd-07 > >Hello, > >> The backbone is supposed to be an Ethernet or a similar high-capacity >> link, so it should have little problem with that load. > >Agreed. > >> the idea was to enable other nodes to live on the backbone link and ? >> communicate with the 6lowpan nodes without requiring any 6lowpan-specific >> code. Those other nodes will speak 4861 only. > >Is the NA/NS solely to exchange information about the whiteboard between the >ERs? > >If so, they could perform a proxy-ND to respond to NS directed at nodes on >the 6LoWPAN. > >Then some other method to keep whiteboards up to date could be used. > >I'm not advocating such a thing, just saying if the clutter of 4861 traffic >on the Ethernet side of the ER was an issue I would think there would be >other solutions! > >Regards, > > -Colin > >-----Original Message----- >From: Carsten Bormann [mailto:[email protected]] >Sent: November 17, 2009 4:49 PM >To: Alexandru Petrescu >Cc: Colin O'Flynn; 'Pascal Thubert (pthubert)'; 'Ralph Droms (rdroms)'; >'6lowpan' >Subject: Re: [6lowpan] Thoughts on draft-ietf-6lowpan-nd-07 > >On Nov 17, 2009, at 16:08, Alexandru Petrescu wrote: > >> Is it efficient for the Edge Router to send a myriad of Neighbor >> Advertisement messages (which are addressed to a link-layer multicast >> address, and a L3 multicast address) on the backbone? > >Well, we try to be fully 4861-compliant on the backbone. >The backbone is supposed to be an Ethernet or a similar high-capacity link, >so it should have little problem with that load. > >> Why cluttering the backbone? > >Because that's what 4861 does to you? :-) > >Of course, the ERs could speak a different protocol between themselves, but >the idea was to enable other nodes to live on the backbone link and >communicate with the 6lowpan nodes without requiring any 6lowpan-specific >code. Those other nodes will speak 4861 only. > >Gruesse, Carsten > _______________________________________________ 6lowpan mailing list [email protected] https://www.ietf.org/mailman/listinfo/6lowpan
