Vince, Gabor,

It is perhaps useful for this discussion, and for the development of the 
discovery protocol, to distribute to the PAWS group the UK requirements in this 
area. These requirements are captured in the draft of the ETSI Harmonised 
Standard:


*        At start up and before initiating any transmissions the Master WSD 
shall locate and consult a listing of approved WSDBs relevant to its 
geographical domain. [The Master WSD shall not transmit if it cannot consult 
the list].

*        In order for the master WSD to continue to use an approved WSDB, it 
shall also reconsult this listing in accordance with the periodicity, N minutes 
relevant to its geographical domain of operation. N will be specified in the 
same listing as the approved WSDBs.

*        A master WSD shall not request operational parameters from (i.e., 
query) a WSDB that is not on the list of approved WSDBs relevant to its 
geographical domain.

*        Once the time specified (N) has expired, the master WSD shall consult 
the listing of approved WSDBs again relevant to its geographical domain before 
contacting a WSDB.

*        If the list is not accessible after the time specified by N has 
expired, the WSD shall

o   continue to use the list that it already holds, and

o   reconsult the weblisting at least as frequently as once every 2 hours 
thereafter but not more frequently than once per hour until such time as when 
the list can be accessed


Secondly, I wonder whether it would be better to keep the UE behaviour with 
regards to discovery and update of database list out of this protocol 
specification. That is, the draft-ietf-paws-protocol would make the assumption 
that the device has the URI of an approved database and not would worry about 
how it got it. It looks to me that some of the requirements you discuss below 
could be left implementation dependent, and others would be addressed by the 
database discovery protocol.

Regards,
Cesar

From: [email protected] [mailto:[email protected]] On Behalf Of Vincent 
Chen
Sent: 04 April 2013 20:26
To: [email protected]
Cc: [email protected]
Subject: Re: [paws] Database Discovery: static provisioning

Gabor,

Acknowledged. I'll take another stab at the additional points on how to 
maintain the lists.

On Mon, Apr 1, 2013 at 10:05 AM, 
<[email protected]<mailto:[email protected]>> wrote:
Vince,

This is a good start, however I think it may worth adding some more context to 
it. For instance, that some regulators certify a limited number of databases 
for operation in WS; that some regulators plan to maintain a website listing 
all approved databases, others may not.

The document also needs to address how to keep the preconfigured list of 
databases up-to-date.
Eg, when a preconfigured certified DB, which the master used to contact, is 
going to shut down/go out of business/close down.
In case a listing web site exists, should the master every now and then check 
if its preconfigured list of DBs matches with the list on the web site, and 
update accordingly.
Master error handling: if one of the DB on in its preconfigured list is 
contacted, and there is no response, or there is an error response (eg 102 
unsupported), what should the master do next.
What if none of the preconfigured DBs work.

The behavior to some of the points above may be obvious, but I think it still 
needs to be spelled out.


-          gabor

From: [email protected]<mailto:[email protected]> 
[mailto:[email protected]<mailto:[email protected]>] On Behalf Of ext 
Vincent Chen
Sent: Wednesday, March 27, 2013 10:10 AM
To: [email protected]<mailto:[email protected]>
Subject: [paws] Database Discovery: static provisioning

All,

At the F2F, it was decided to update the language in the 
draft-ietf-paws-protocol to explicitly allow static provisioning, while leaving 
room to adopt dynamic provisioning, when it's defined.

Here is the proposed language. Comments are welcomed. Thanks

-vince

------------------------------


4.1.  Database Discovery

   The Device MUST determine the URI for the Database before it can send
   PAWS messages.  The Device MAY be provisioned statically with the URI
   of one or more Databases.  The Device SHOULD be provisioned with the
   URI of all the databases for which it is certified or otherwise
   permitted to operate.

   The Database MAY redirect a PAWS request by returning a HTTP 3xx
   response, as defined by HTTP/1.1 [RFC2616].  The Database MUST
   provide the redirect URI in the Location header of the 3xx response,
   and the Device MUST handle redirects by using the Location header
   provided by the Database.  When redirecting, the Device MUST observe
   the delay indicated by the Retry-After header.  The Device MUST
   authenticate the Database that returns the redirect response before
   following the redirect.  Additionally, the Device MUST authenticate
   the Database indicated in the redirect.  Because the Device may
   communicate with the Database without user interaction and because
   the Device authenticates the Database, when the response code is 301
   (Moved Permanently), the Device MAY redirect without asking a user
   for confirmation, which is an exception to the HTTP/1.1 [RFC2616]
   requirements for HTTP POST methods.

   The Device MAY obtain the URI of one or more Databases dynamically
   from authorized and authenticated entities.  The Device SHOULD use
   dynamic provisioning of Database URI when the mechanism is defined.




--
-vince

________________________________

******************************************************************************************************************
For more information visit www.ofcom.org.uk

This email (and any attachments) is confidential and intended for the use of 
the addressee only.

If you have received this email in error please notify the originator of the 
message and delete it from your system.

This email has been scanned for viruses. However, you open any attachments at 
your own risk.

Any views expressed in this message are those of the individual sender and do 
not represent the views or opinions of Ofcom unless expressly stated otherwise.
******************************************************************************************************************
_______________________________________________
paws mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/paws

Reply via email to