Hi stefano,
On Wed, Apr 27, 2011 at 11:17:33AM +0200, stefano previdi wrote:
> On Apr 27, 2011, at 10:22 AM, Sebastian Kiesel wrote:
>> Hi,
>>
>> On Wed, Apr 27, 2011 at 09:15:11AM +0800, ?????? wrote:
>>> hi, everyone:
>>>
>>> have the ALTO considered the use cases of wireless, which means how
>>> to make
>>> the selection of the peers in the wireless environment?
>>
>> the ALTO protocols and procedures feature mechanisms that can be
>> leveraged in a mobile / wireless scenario. IMO there are two issues:
>>
>> 1. When a client is moving between different sections of an access
>> network it may have to find a new ALTO server which is able
>> to give guidance that is useful at the new client position.
>> draft-kiesel-alto-3pdisc-05, sec. 1.3 states:
>>
>> o A change of the IP address at an interface invalidates the result
>> of the ALTO server discovery procedure. For instance, if the IP
>> address assigned to a mobile host changes due to host mobility,
>> it
>> is required to run the ALTO server discovery procedure for the
>> new
>> IP address without relying on earlier gained information.
>
>
> mobility is often at layer-2 and this mean you will need some other
> mechanisms in order to enrich your maps/ecs with wireless-l2 derived
> topology info.
I agree. But the creation of maps based on the (wireless) topology and
other {cost,distance,performance,...}-related information as well as
feeding them into the ALTO server is out of scope of the protocol spec.
The paragraph above is about ALTO server discovery:
If the client notices that it has been assigned a different IP address,
one reason may be a significant movement in the network, e.g., handover
from one mobility anchor to another, and therefore a new ALTO server
discovery might be required (of course, there might be other reasons for
getting a new IP addres, but doing a new discovery then won't hurt).
Are there any networks using layer-2 mobility which are so huge, that a
client should discover and use different ALTO servers while moving
around even though it can retain the same IP address?
Thanks,
Sebastian
_______________________________________________
alto mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/alto
