在 2015年3月25日 星期三，下午6:54，Alper Yegin 写道：
> > > > > > > > 1. Regarding the definition of “fixed IP address” in the draft: > > > > > > > > “- Fixed IP Address > > > > This is what standard Mobile IP provides with a Home Address (HoA). The > > > > mobile host is configures a HoA from a centrally-located Home Network. > > > > Both IP session continuity and IP address reachability are provided to > > > > the mobile host with the help of a router in the Home Network (Home > > > > Agent, HA). This router acts as an anchor for the IP > > > > address of the mobile host.” > > > > > > > > If this is equal to HoA, then RFC5014 already cover that. We do not > > > > need to repeat it here with another name. > > > > > > > > > > > > > This is not equal to "HoA". > > > This is equal to "HoA permanently allocated on a HA in the core network" > > > (as opposed to "HoA temporarily allocated on a HA in the access network") > > > > > The draft says: “This is what standard Mobile IP provides with a Home > > Address (HoA)...” If it is not equal to HoA, need clarification in the > > draft. > > > > > Draft says "This is what standard Mobile IP provides with a Home Address > (HoA). The mobile host is configures a HoA from a centrally-located Home > Network. " > > If this is not clear enough, we can certainly elaborate more on that in the > I-D. > Yes. It needs more elaboration. > > > > > > 2. Regarding the definition of “sustained IP address” in the draft: > > > > > > > > "- Sustained IP Address This type of IP address provides IP session > > > > continuity but not IP address reachability. It is achieved by ensuring > > > > that the IP address used at the beginning of the session remains usable > > > > despite the movement of the mobile host. The IP address may change > > > > after the termination of the IP session(s), therefore it does not > > > > exhibit persistence. " > > > > There is no clear dividing line between fixed IP address and sustained > > > > IP address. Whether the IP address is used for reachability is not > > > > determined by the IP address itself. For example, even when the MN get > > > > a HoA, after it moves to another location of the network, it may decide > > > > to release current HoA and get another HoA, in this case the "fixed IP > > > > address" becomes a "sustained IP address". > > > > > > > > > > If the IP stack on the host releases the IP address, then of course it's > > > not a "fixed IP address". > > > Please see the definitions of these terms in the I-D. > > > > > > > > > > Further more, the reachability normally is implemented by domain name > > > > instead of IP address. For example, we reach “Google” by its domain > > > > name, never by it’s server’s IP address. > > > > > > > > Using temporary private IP address we can also achieve the goal of > > > > “reachability”. For example, using dynamic DNS, as shown in > > > > http://hsk.oray.com/ , it can provide reachability even the host get a > > > > private IP address. > > > > > > > > > > You had said this before, and I had explained it. > > > Nevertheless, let me recap: > > > You cannot ensure an ongoing IP flow continues w/o interruption if you > > > simply rely on dynamic DNS. Ongoing flows break even if you update the > > > DNS. > > > Furthermore, even if you ignore the ongoing flows, also note that DNS > > > clients have a cache, hence a dynamic DNS update cannot be > > > instantaneously reflected on the hosts. > > > So, you cannot provide full mobility solution by relying on dynamic DNS. > > > > > > > > The point here is “reachability” instead of “mobility”. > > Further more, even mobile IP may lost some packet during handover. > > > > > Not sure if this point has any impact on the discussion. > > The point is: in the draft, whether support “reachability” is the distinction between “fixed IP” and “ sustained IP”, but the truth is any type of IP address can provide “reachability”. So there is no clear dividing line between “fixed IP” and “ sustained IP” in the definition. That is why the definition of the IP types is not valid. > > > > 3. Regarding the definition of “nomadic IP address”: > > > > > > > > “- Nomadic IP Address > > > > This type of IP address provides neither IP session continuity nor IP > > > > address reachability. The IP address is obtained from the serving IP > > > > gateway and it is not maintained across gateway changes. In other > > > > words, the IP address may be released and replaced by a new IP address > > > > when the IP gateway changes due to the movement of the mobile > > > > host.” > > > > > > > > Seems this IP address is the IP address that we normally used in most > > > > cases. If this is the case, why we need a new name for it? > > > > > > > > > > > > > If you don't name it, how would you refer to it in this context? > > If the justification of naming IP address as “fixed IP” and “ sustained IP” > > is not valid, then we may not necessary need a new name for normal IP > > address. > > > > I and the WT#1 believe that justification is valid. > If you believe otherwise, please elaborate. > > > Pls see above comment. Dapeng > > Alper > > > > > > > Dapeng > > > > > > > > > Alper > > > > > > > > > > > > > > -- > > > > Dapeng Liu > > > > > > > > > > > > 在 2015年3月25日 星期三，下午2:02，Alper Yegin 写道： > > > > > > > > > Hello Dapeng and Alex, > > > > > > > > > > I hope you had a chance to digest our responses to your comments and > > > > > questions about the API work. > > > > > If you have any remaining issues, please let us know over the email > > > > > at your earliest convenience. > > > > > It'd be good if you can articulate them in detail. > > > > > > > > > > > > > > > Thanks. > > > > > > > > > > Alper > > > > > > > > > >
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