Hi Joe, I read your document and, for the applications I am concerned with, I still think what I am doing is the better approach. One thing that you may not have gathered is that the AERO interface does not maintain a replicated copy of the entire IP forwarding table; it only keeps neighbor cache entries for its currently active sets of neighbors. For AERO Clients, this would include the default router(s) and any peers that it has recently received Redirects from. For AERO Servers, the neighbor cache would include entries for the current list of associated Clients. So, the AERO interface is not a full-blown IP router; it is a neighbor discovery engine for its active set of neighbors.
So, unlike a dynamic routing protocol the AERO interface uses IPv6 Neighbor Unreachability Detection (NUD) instead of routing protocol keepalives to maintain reachability. There is also no routing protocol control messaging going out over the underlying data links - it is simply data packets plus occasional NUD messages. I noticed that your document was from 1997, which is the same year I started with SRI International. I think that was right around the time you and I first met. Thanks - Fred [email protected] From: Joe Touch [mailto:[email protected]] Sent: Tuesday, December 06, 2016 2:48 PM To: Templin, Fred L <[email protected]>; Lucy yong <[email protected]>; Brian E Carpenter <[email protected]>; [email protected] Subject: Re: [Int-area] Some thoughts on draft-yong-intarea-inter-sites-over-tunnels On 12/6/2016 2:43 PM, Templin, Fred L wrote: Hi Joe, I am looking at multilink nodes like manned aircraft and unmanned aerial vehicles that may have many active aviation data links, e.g., SATCOM, LDACS, 4G, AeroMACS etc. The links will be either available or unavailable at various phases of flight. But, AERO lays down a single IP layer interface (the aero0 interface) so that the aviation data links are seen as underlying interfaces each having one or more addresses. These underlying addresses are then seen as the L2 addresses for the AERO interface. You can accomplish the same thing using virtual interfaces using dynamic routing. See the following: J. Touch, T. Faber, "Dynamic Host Routing for Production Use of Developmental Networks<http://www.isi.edu/touch/pubs/icnp97/>," in Proc. ICNP '97, Atlanta, Oct. 1997, pp. 285-292. Underlying interfaces may come up and go down dynamically during a flight, and their addresses may change dynamically, e.g., if they hand over from cell tower A to cell tower B. It is AERO's job to take care of any mobility related links and always keep neighbors informed of the current L2 addresses and availability. But, it all still looks like a single interface (aero0) to the IP layer. You can do the same thing using IP forwarding without needing to bury the forwarding decisions inside the link. Joe
_______________________________________________ Int-area mailing list [email protected] https://www.ietf.org/mailman/listinfo/int-area
