RE: [802.21] transport layer for MIH IS.
David,
as Perez says, we must realistically expect that 802.21 signaling (remote events, etc.) will be implemented both with IP-based solutions and L2 specific solutions. The reason is quite straightforward: do you want to deploy 802.21 ASAP? Well, use an overlay solution where transport is 802.21. If we rely just on L2, it may take a long time before anybody can actually use 802.21. Whether somebody is interested in the IP transport or not is another issue. Now, the two real question is whether or not all this discussion is in the scope of 802.21. As I mentioned in my slides, I believe 802.21 shall not define any transport, only logic of MIH functions, interfaces, IEs, etc. 802.21 can develop recommendations for the specific link layer groups and for IETF, 3GPP or 3GPP2 on how to take the outcome of 802.21 and implement it, but I don't see how 802.21 can define such implementation. As Perez says, if transport over IP is to be defined, IETF is the place to go. How specifically this w!
ill be done is out of scope of 802.21.
David, I also have the same question that Ajoy has: why do you believe L2 transport is more reliable?
Stefano
-----Original Message-----
From: owner-stds-802-21@LISTSERV.IEEE.ORG
[mailto:owner-stds-802-21@LISTSERV.IEEE.ORG]On Behalf Of ext David Xiang
Sent: Thursday, January 20, 2005 5:23 PM
To: STDS-802-21@LISTSERV.IEEE.ORG
Subject: Re: [802.21] transport layer for MIH IS.
I mean how to transfer the IS through air-interface. Is the IS carried in IP
play load which doesn't care what media interface carrier it or direct in L2
payload of that specific media interface (e.g IE of MAC management message
for 802.11, 16)?
David
On 1/20/2005 3:30 PM, David Xiang wrote:
> When we consider the complexity of .21 implementation and interaction with
> other media standard, we need to think of our transport layer for
> information service exchange with network or peer, though it seems out of
> scope of .21 from most of the proposals.
> I saw two ideas of transport layer from the proposals: IP application, and
> L2. I just want to get your thoughts on which one is better.
Transport across network elements must be IP type, which of course is
carried
within L2 Ethernet frames.
In .21 new Ethernet frames (type .21) is in scope, IP is questionable. It
may be
an IETF domain to pick form the .21 standard.
>
> IP:
> Pros: 1. Generic and less impact on other media standard,
> 2. Give more implementation flexibility for .21 information service
> and other requirements.
> 3. More easy to be implemented.
>
> Cons: 1. slow
> 2. Not reliable or robust as L2 transport, but IP application can
> become robust with some good mechanisms.
>
> L2:
> Pros: 1. faster
> 2. More robust
>
> Cons: 1. Too rely on other media standard which may not good for .21
> implementation.
> 2. Not flexible, any time .21 do some changes on SI, it may request
> all other media standard to do some changes too.
>
> Any thoughts?
It is not one or the other, it will have to be both if we include MIH
exchange
between a station and MIH IS DB at the core network.
The big question is how do we define the IP protocol associated with the
exchange of IP messages between the terminal and the IS network element? is
it
an IETF follow up? or within the scope of IEEE802.21?
>
> Thanks,
>
> David