Hi Alper, Thanks for your reply. Please see inline ">>".
Regards, Seil Jeon -----Original Message----- From: Alper Yegin [mailto:alper.ye...@yegin.org] Sent: Friday, May 22, 2015 11:08 AM To: Seil Jeon Cc: dmm@ietf.org Subject: Re: [DMM] [dmm] #49 (ondemand-mobility): full on-demand mobility support Hi Seil, Thanks for creating the ticket. Please see below. > > #49: full on-demand mobility support > > The three proposed flags express a "type" of source IP address an application wants to get to the IP stack. Particularly, the sustained IP address is proposed to provide on-demand IP session continuity, which activates IP mobility once the terminal moves across other access network. > While the terminal stays at the same network where the session is initiated, regular IP routing is applied. > > The on-demand draft does not assure provide the full on-demand mobility for all scenarios by merely indicating the Socket API, IPV6_REQ_SUSTAINED_IP. An example scenario raising the aforementioned issue is as follows; > > 0. The MN is configured with one or more Nomadic IP addresses. > > 1. Once an app. requests "sustained IP address" to the IP stack, and it will obtain a sustained IP address through a protocol procedure between the terminal and network. > > 2. Other app. initiated over the same access network will use the same sustained IP address while the terminal remains connected at the same access network. > > 3. The terminal moves to another access network and a new app. requests a sustained IP address with the Socket API to the IP stack. Since a sustained IP address is already available in the IP stack, the sustained IP address is assigned to the new app. > Yes, that's what happens. You are not pointing to an issue up until this point, right? Because, you continuing your email with a "Besides" gives the impression that you are pointing to an issue, but I don't see any issue captured in the above text. >> There is an issue. Maybe, we need to be synchronized how have you thought and defined the meaning of "on-demand mobility". As far as I know, there are two meanings; one is that by imposing capability among IP address reachability and IP session continuity, needed for an application, into a source IP address, on-demand mobility could be achieved; as the other meaning, it can be rephrased and detailed with dynamic mobility, which should be applied in the use of sustained IP address. A new application needs to have non-anchored sustained IP address. This is our consistent claim. Non-optimal routing issue has been raised in DMM Requirement document in RFC 7333, which should be critically considered in the solutions. > Besides, in case sustained IP address allocation is used default, there may be multiple sustained IP addresses including newly obtained sustained IP address over the new access network in the IP stack. However, when an app. is initiated, the IP stack may not select the new one in the context of the default source IP address selection mechanism [RFC6724][RFC5014]. > OK, is the issue following: When there are multiple sustained IP addresses, how does the IP stack pick one among them? >> As mentioned and specified in our draft http://tools.ietf.org/html/draft-sijeon-dmm-use-cases-api-source-00, if there is no additional preference, we can leave selection to the default source address selection mechanism. BUT if we have specific preference among multiple sustained IP addresses and an initiated application wants to have non-anchored sustained IP address over currently attached access network, the proposed flag is essential. > For providing the full on-demand mobility, a new flag is needed, letting the IP stack request a new sustained IP address or choose a sustained IP address not requiring IP mobility anchoring when an application is initiated, among the existing ones in the IP stack. > Your flag is not a solution to what I captured above. It does something else: Instruct the IP stack to go get a new sustained IP address whether there is already one or more configured on the stack or not. >> Answered in the above. Alper > -- > -------------------------+---------------------------------------------- > -------------------------+--- > Reporter: | Owner: draft-ietf-dmm-ondemand- > seilj...@av.it.pt | mobil...@tools.ietf.org > Type: defect | Status: new > Priority: critical | Milestone: > Component: ondemand- | Version: > mobility | Keywords: on-demand mobility > Severity: Submitted | > WG Document | > -------------------------+---------------------------------------------- > -------------------------+--- > > Ticket URL: <http://trac.tools.ietf.org/wg/dmm/trac/ticket/49> > dmm <http://tools.ietf.org/dmm/> > > > _______________________________________________ > dmm mailing list > dmm@ietf.org > https://www.ietf.org/mailman/listinfo/dmm _______________________________________________ dmm mailing list dmm@ietf.org https://www.ietf.org/mailman/listinfo/dmm
