Re: [H.323 Mobility:] questions on MTD-016
Hi Stephen,
I have a couple more questions.
First, what exactly is the BG in your contribution? I know that there is such an element in GPRS and it is used in cases, when the visited PLMN always routes the packets of the visiting user to the user's home PLMN. I assume that this BG is supposed to serve a similar purpose, am I right?
Second, based on the above mentioned purpose of the BGs and to the fact that in your contribution you state that the HLF selects a gatekeeper in the home network of the user to which the terminal/user will be registered, I assume that this model that you are proposing is only applicable for the "Virtual Home Environment" model (i.e. service execution in the home network). Am I right in this assumption, and if not, could you explain how this model could be used in the "Service Execution in the Visited Network" model?
Furthermore, I would not use the terms home/visited network, because there are evidently differing views on what a network means. I suggest that we use the already defined terms Home/Visited Administrative Domain instead for the meaning of home/visited network that I think you're thinking of.
-Jaakko
-----Original Message----- From: EXT Stephen Terrill [mailto:stephen.terrill@ERICSSON.COM] Sent: 13. April 2000 14:42 To: ITU-SG16@mailbag.cps.intel.com Subject: Re: [H.323 Mobility:] questions on MTD-016
Hi,
I shall try to answer some of these questions below.
Regards,
..//steve
"Kumar, Vineet" wrote:
Stephen,
I have a couple of questions on your contribution MTD-016.
These are:
- H.323 already has mechanisms for discovering the
gatekeeper. Are you suggesting in your contribution that the terminal should discover the VLF instead of the visiting gatekeeper ? Or, are you assuming that the VLF is integrated in the visiting gatekeeper ?
This can be discussed - I was of the opionion that we should discover the VLF and send the registration to the home environment after that. However, we haven´t agreed on the role of the VLF, and visited gatekeeper, home gatekeerp and HLF - when we come to agree on what these are, my proposal may change.
- In H.323, authentication of the terminal and the
gatekeeper is done at the time of discovery. In fact, in H.323 all messages between the terminal and the gatekeeper can be authenticated and the message integrity preserved. In your contribution, authentication is done at the time of registration. Why is this preferable to what is already in H.323 ?
I would be interested to understand which gatekeeper you were considering should do the authentication. I would assume that the real authentication would have to be done at home - as such it would be necessary to find the visited network services, and then register/authenticate at home.
- What is the reason for the information flow from the HLF
to the home gatekeeper, and from the home gatekeeperr to the HLF ? I don't think we can assume that there is only one home gatekeeper that the terminal may be using. In fact, the home gatekeeper may not have any information about the user.
I certainly don´t assume that there is only one home gatekeeper. I assume that there will be a number of home gatekeepers, but perhaps only one (or few) HLFs. In this case, we need an function to select the gatekeeper that the user is going to camp on - and this may depend on load, subscriber profile, policy - or a lot of things.
Regards, vineet
Hi Jaakko,
Perhaps it should have been a BE instead of a BG, sorry for the confusion. I understood from the previous work, not all of which I have had the priveledge to be a part of, the communication could be directly between the two networks, or via the BEs.
Regarding the service execution paridigm what "services" are you considering?
Regards,
..//steve
Jaakko Sundquist wrote:
Hi Stephen,
I have a couple more questions.
First, what exactly is the BG in your contribution? I know that there is such an element in GPRS and it is used in cases, when the visited PLMN always routes the packets of the visiting user to the user's home PLMN. I assume that this BG is supposed to serve a similar purpose, am I right?
Second, based on the above mentioned purpose of the BGs and to the fact that in your contribution you state that the HLF selects a gatekeeper in the home network of the user to which the terminal/user will be registered, I assume that this model that you are proposing is only applicable for the "Virtual Home Environment" model (i.e. service execution in the home network). Am I right in this assumption, and if not, could you explain how this model could be used in the "Service Execution in the Visited Network" model?
Furthermore, I would not use the terms home/visited network, because there are evidently differing views on what a network means. I suggest that we use the already defined terms Home/Visited Administrative Domain instead for the meaning of home/visited network that I think you're thinking of.
-Jaakko
-----Original Message----- From: EXT Stephen Terrill [mailto:stephen.terrill@ERICSSON.COM] Sent: 13. April 2000 14:42 To: ITU-SG16@mailbag.cps.intel.com Subject: Re: [H.323 Mobility:] questions on MTD-016
Hi,
I shall try to answer some of these questions below.
Regards,
..//steve
"Kumar, Vineet" wrote:
Stephen,
I have a couple of questions on your contribution MTD-016.
These are:
- H.323 already has mechanisms for discovering the
gatekeeper. Are you suggesting in your contribution that the terminal should discover the VLF instead of the visiting gatekeeper ? Or, are you assuming that the VLF is integrated in the visiting gatekeeper ?
This can be discussed - I was of the opionion that we should discover the VLF and send the registration to the home environment after that. However, we haven´t agreed on the role of the VLF, and visited gatekeeper, home gatekeerp and HLF - when we come to agree on what these are, my proposal may change.
- In H.323, authentication of the terminal and the
gatekeeper is done at the time of discovery. In fact, in H.323 all messages between the terminal and the gatekeeper can be authenticated and the message integrity preserved. In your contribution, authentication is done at the time of registration. Why is this preferable to what is already in H.323 ?
I would be interested to understand which gatekeeper you were considering should do the authentication. I would assume that the real authentication would have to be done at home - as such it would be necessary to find the visited network services, and then register/authenticate at home.
- What is the reason for the information flow from the HLF
to the home gatekeeper, and from the home gatekeeperr to the HLF ? I don't think we can assume that there is only one home gatekeeper that the terminal may be using. In fact, the home gatekeeper may not have any information about the user.
I certainly don´t assume that there is only one home gatekeeper. I assume that there will be a number of home gatekeepers, but perhaps only one (or few) HLFs. In this case, we need an function to select the gatekeeper that the user is going to camp on - and this may depend on load, subscriber profile, policy - or a lot of things.
Regards, vineet
participants (2)
-
Jaakko Sundquist -
Stephen Terrill