Danny,
Thank you for explaining. I read this draft without knowing the back story, and 
I did not glean the explanation below from the draft.

If you want the explanation recorded for posterity, it should be in the draft.

Having said that, it would be better, in my opinion, if this API is NOT 
specific to proxy-based architectures.
An application programmer is concerned with whether it needs a long-lasting 
address or whether an ephemeral address is acceptable.
(i.e., am I a client or a server?)

I don’t see many application programmers concerned with on-demand DMM per se.

-Dave


From: Moses, Danny [mailto:[email protected]]
Sent: Monday, December 19, 2016 6:16 AM
To: Lorenzo Colitti; Dave Dolson
Cc: [email protected]; [email protected]
Subject: RE: [DMM] WGLC for draft-ietf-dmm-ondemand-mobility-08 --

OK, two is a crowd…

I am thinking of the appropriate example and will send a draft for review.

I think there might be a confusion regarding the HOME and CoA flags. Although 
they are also related to mobility and enable applications a selection between 
two types of source IP addresses, they are very different and should not be 
discussed in the context of OnDemand.

The HOME and CoA flags are defined to enable an application to select between a 
HOME address and a Care-of address. This is in the context of Mobile IP (no 
Proxy Mobile IP) in which the network allocates both a Home Address and a 
Care-of Address to the mobile host. These flags enable applications to select 
the type of IP session continuity in this context (where the host is one 
termination point of the tunnel).

The context of the OnDemand draft is PMIP (or any proxy-based architecture, 
like GTP). In this context, the mobile host does not have a Home Address and a 
Care-of-Address since the tunnel is terminated by a proxy agent. So an 
application cannot specify its preference regarding Home or CoA.

Danny


From: Lorenzo Colitti [mailto:[email protected]]
Sent: Monday, December 19, 2016 03:04
To: Dave Dolson <[email protected]>
Cc: Moses, Danny <[email protected]>; 
[email protected]; [email protected]
Subject: Re: [DMM] WGLC for draft-ietf-dmm-ondemand-mobility-08 --

rOn Fri, Dec 9, 2016 at 3:59 AM, Dave Dolson 
<[email protected]<mailto:[email protected]>> wrote:
5. Are there new errors from bind(), listen() or connect(), etc.?
E.g., socket option is FIXED, but user explicitly specified a COA address to 
bind to?

+1. An implementer would probably choose to return EADDRNOTAVAIL if an API 
requested a type of address that is not available, but the draft makes no 
mention of that.

The draft also fails to mention which of the APIs will result in a request to 
the network (which can block for a long period of time) and which will not. It 
will be quite unexpected to app developers if system calls such as bind() and 
setsockopt(), which always return immediately, can suddenly block for whole 
seconds. It would also be highly unexpected if connect() on a UDP socket took a 
long time since it currently returns immediately.

I don't think it's a good idea to overload these existing system calls with new 
"obtain an prefix from the network" semantics. It's better to add a new system 
call for that.

---------------------------------------------------------------------
A member of the Intel Corporation group of companies

This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.
_______________________________________________
dmm mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/dmm

Reply via email to