And Now for Something Completely Different (was Re: IPv6 news)

Sun Oct 16 09:23:52 UTC 2005

Tony Li wrote:
> 
> 
>> How is a split between locator / identifier any different logicaly  
>> from the existing ipv4 source routing?
> 
> 
> 
> IPv4 source routing, as it exists today, is an extremely limited  
> mechanism for specifying waypoints along the path to the destination.

IOW the end stations were supposed to be able to tell eachother how to 
route to eachother. Obviously that does not work in todays internet. But 
  that was a seperation between the endpoints ID and the routing of the 
packet.

> 
> This is completely orthogonal to a real identifier/locator split,  which 
> would divide what we know of as the 'address' into two separate  spaces, 
> one which says "where" the node is, topologically, and one  which says 
> "who" the node is.   One might use the identifier in the  TCP 
> pseudo-header, but not the locator, for one example, immediately  
> allowing both mobility and multi-homing.

Do you mean adding a second address space to be used by all l3 protocols?

Or adding a second address space for every L3 protocol? Or adding a 
layer 2.5 address space? That appears to be what shim6 is.

Also my original question -- How do I send my packet to the other node?

I cant just address my packet to the ID, I have to use either 
information supplied by that node or by a third party.

Source routing or routing tables.

If this decoupling depends on inband negotiated information, than this 
allows survivability, but it is not multihoming where multihoming is 
described as what we do now.

> 
> Tony
> 
> 
> 