Re: caller ID and implementer's guide
Pete,
I would agree with what you are saying here, coming from a public network background I would agree with your analysis. We seem to be talking about a number of different identity services which we seem to be mapping onto the calling party number information element. I think if we are going to include the octet 3 and octet 3a we should be clear about which service we are supporting.
Presentation identity services: Used by the terminating end to return a call or reference a database, this number normally has very slim requirements for authenticity, and could be any number within the E.164 number range. Subscriber identification services: Identifies the subscriber, may be used for malicious call identity services, this number must be authenticated and is only ever provided by the network. Location identification services: Identifies the location of the call, may be used for emergency services in cases, this number must be authenticated and is also traditionaly provided by the network.
From what a few others are saying, their requirement would be to support the
first case, presentation identity services. In most cases for communicating identities between PBXs that have no real need for some form of suscriber identification or location identification. The security and authentication tokens which you mention, would definitly be required if an emergency call is made. This is obviously a big issue and possibly can be dealt with seperatly from the short term requirements for presentation identity services.
The policy I think that should be adopted is that if there is any form of interworking to the SCN then the number that is sent from the VoIP network in the absence of some form of authentication should be considered 'user provided not verified'. The Gateway to the SCN should then take the same action as if it received a call from a PBX it didn't trust and add some form of other identity, which would be a default marked against the trunk.
To satisfy those people like myself and Pete, where we add octet 3 or octet 3a we should leave a note that says "this part of the protocol is not equipped for use by emergency services and malicious call identification and therefor wherever a calling party number is included it should be considered as user provided not verified and the indicators marked accordingly"
I will of course leave it up to you how you decide to include octet3a and octet3.
Cheers
John
-----Original Message----- From: Pete Cordell [SMTP:pete.cordell@BTINTERNET.COM] Sent: 13 May 1999 05:05 To: ITU-SG16@MAILBAG.INTEL.COM Subject: Re: caller ID and implementer's guide
Paul,
I now understand where you are coming from when you say that the first scheme is proprietary.
However, I think it's slightly different because, although someone might be upset if you sent H.261 data to an H.263 decoder, they are unlikely to sue you for disclosing information that has been requested to be kept private, as might be the case if the calling party's telephone number is displayed when it has been requested not to be. Hence the need for trust, because if the entity you send the information to does not honour your request, you could end up with some very expensive legal fees!
(As a side note, some sort of calling party id is probably required for legal reasons, such as tracing emergency calls. Hence remaining private by not including the calling party id is not an option. I'm not sure if this is what we are talking about , but what is really needed is something that only lets those that are allowed to know to access the information. The case of the switched network is slightly different to that of IP because the former is essentially a secure network behind a firewall. The Internet and most other IP networks does not generally mirror this model and so a different solution is required. What is probably required is a supplementary service that does call tracing using suitable cryptographically secure tokens that are known only to those that are allowed to do call tracing.)
Pete
============================================= Pete Cordell pete.cordell@btinternet.com =============================================
-----Original Message----- From: Paul Long Plong@SMITHMICRO.COM To: ITU-SG16@MAILBAG.INTEL.COM ITU-SG16@MAILBAG.INTEL.COM Date: 12 May 1999 14:20 Subject: Re: caller ID and implementer's guide
Pete,
Sorry. I did indeed believe that you were saying that a vendor could take ownership of an IE, which would be a proprietary and rather dangerous solution. "We" or "SG16" in place of "you" might have been a better
choice of
words. Your first solution is still proprietary, though. Your counter
argument
is weak because one could use it for all otherwise proprietary features,
e.g.,
"only send H.261 on a channel established for H.263 to an entity that you trust to expect this."
Paul Long Smith Micro Software, Inc.
-----Original Message----- From: Pete Cordell [SMTP:pete.cordell@BTINTERNET.COM] Sent: Wednesday, May 12, 1999 6:27 AM To: ITU-SG16@MAILBAG.INTEL.COM Subject: Re: caller ID and implementer's guide Paul, I disagree that these are proprietary solutions. The first is a matter of policy and so falls into a slightly greyarea, but ideally the standard would say something like 'only send
presentation
restricted information to an entity that you trust to honour therequest.'
The second is definitely NOT an action you could take at aproprietary
level as the standards body still holds the right to define new IEs.
Any
such action would have to be approved by the standards body. When I
said
'...YOU could take further ownership...', the 'you' was intended to refer
to
SG16.
As such a change is small and localised, it would be safe toimplement
it even if it was mentioned only in a determined document (which is
the
way the procedure is supposed to work after all anyway!) which could be achieved at the Chile meeting. A fix in the ASN.1 would have to wait for the decided version as that needs to wait until all such additions are
present.
Pete ============================================= Pete Cordell pete.cordell@btinternet.com =============================================
participants (1)
-
John Talbot