Date: Fri, 29 May 2009 17:34:21 +0200 From: "Pascal Thubert (pthubert)" <[email protected]>
>From: Richard Kelsey [mailto:[email protected]] >To: Pascal Thubert (pthubert) > > Date: Fri, 29 May 2009 11:55:10 +0200 > From: "Pascal Thubert (pthubert)" <[email protected]> > > The current draft inherits source address validation text from the > backbone router draft that's meant to prevent nodes in the LoWPAN from > using any address as source. > > section 7.5. about forwarding by Edge Routers has: > > " > Upon receiving packets on one of its LoWPAN interfaces, the Edge > Router checks whether it has a binding for the source address. If > it does, then the Edge Router can forward the packet; otherwise, > the Edge Router MUST discard the packet. > " > > That was fine for a backbone router in a mesh under > situation but that seems to falls short for route over, > because in that case the Edge Router is not necessarily > the first hop: > >The check described in the passage above seems to be >guarding against the use of a source address that is not >bound within the LoWPAN. It doesn't appear to be concerned >with a LoWPAN node using a source address that is bound to >some other node in the same LoWPAN. For the former, >guarding against the use of an unbound source address, I >don't think it matters whether the Edge Router is the first >hop or not. Agreed but in extended the whiteboard is distributed so if your packet get out the wrong edge router it would filter them out... Pascal, Doesn't the Extended LoWPAN backbone take care of that? >From 7.3: Addresses that are not found in the Whiteboard are queried over the backbone using the ND operation in place for that type of link, ... Either you have a Simple LoWPAN, in which case there is only one Edge Router, or you have an extended LoWPAN, in which case the Edge Routers can query each other over the backbone if they see a source address that is not in their local whiteboard. I think that this works for the Simple and Extended LoWPANs as described in the draft. It would be nice if there were a way of having additional Edge Routers that were not on a high-speed backbone. An Edge Router whose other IP network was another LoWPAN, for example. If that were permitted, a node would have to route packets via an edge router with which it was registered, as you described. -Richard Kelsey ---------------- This message and the information it contains are the proprietary and confidential property of Ember Corporation and may be privileged. If you are not the intended recipient, please do not read, copy, disclose or distribute its contents to any party, and notify the sender immediately. _______________________________________________ 6lowpan mailing list [email protected] https://www.ietf.org/mailman/listinfo/6lowpan
