Re: [rrg] Host changes vs. network changes

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Host-based versus network-based: Could it be that this topic stems purely  
from "shim6-multihoming" versus "lack-of-network-based multihoming" ? Imho: 
Both  hosts and network nodes should be able to trigger a change of path.
 
I believe "host-versus-network based" - discussions should also deal  with 
a topological network view where hosts are as well nodes as are  routers. I 
wouldn't be afraid of it - not wrt scalability.
 
Quote from ALayeredMappingSystem.pdf, taken from the  LISP-list :
"It is unimaginable that an EID is individually allocated to one user. As a 
 result, mapping nodes can store the EID prefix-to-RLOC mapping once an 
item,  which will greatly reduce the scale of mapping storage."
 
Why is this unimaginable? Even the writer of this statement hereby  
demonstrates that he can imagine this.
I guess he worries about the update churn if  mappings between  individual 
EIDs and RLOCs are to be disseminated.
However, by utilizing an existing routable RLOC-location information, no  
dissemination is required at all.
DNS and others may map the user name to IPv4 + geogr.coordinates  (RFC1712) 
as of the last point of routing. The geographical  coordinates are a given 
"third instrument". If both the  host as well as  the router complies with 
it, then routing to the egress-(DFZ?)-node can be  done without churnfull 
mappings and without looking looking at the  dest.IP-address.
 
In some way really all solutions are hierarchical. Yes, including the  
present pure-prefix-building mechanism.
I think a more profound analysis of  hierarchical routing  wouldn't be 
inappropriate. E.g. the mentioned .pdf is pretty fond of 2  hierarchical levels. 
Why just 2 ? Why not more than 2 ?
As you know, myself, I am in favor of 1 (flat) level, i.e. flat topology,  
properly sparsed due to some hierarchical process.
 
Heiner