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Re: addition of TLV to locator ID or locator ID set
Paul Jakma wrote:
I'd have to ask: Why use CGA?
The answer to this question relates to how much dynamism we
want in the address sets. Also, there may be some feature interactions
with sites that want to employ both SEND and SHIM6.
AFAICT, CGA was created specifically because relying on IPSec for
address assignment has bootstrap issues. Hence CGA and SeND.
CGAs were in fact initially developed for another purpose, namely
Mobile IPv6. They are usable in address ownership related tasks,
but to date their usage has been described for secure ND only.
For modes relying on anonymously introduced public-key cryptography,
we won't have bootstrap issues here, so why not use standard IPSec? Is
it just to avoid the size of an AH header on each packet?
How will you communicate the CGA parameters? Is shim to reinvent
portions of IKE in order to communicate public keys? Why not just use
IKE? IPSec is well-understood, widely implemented and deployed. Why
give ourselves the task of reinventing aspects of it?
I can see some of the attractions of HBA, but using CGA beyond the
local-link is stretching it..
There isn't really anything that different in CGA and HBA at this level.
CGA allows dynamic changes. But both need no user input or config,
prior arrangement between parties, or trusted third parties.
Both need an exchange to assure the other party that things are
OK, e.g., we need to communicate the values (not just the key)
used in the hashing process.
RFC 3971 is an example of a protocol that does this. This isn't
IKE. (But a lot of people confuse the use of public keys with
certified public keys, PKIs, and configured security. This isn't
the case for here, however.)
--Jari