Hi Jouni, Kostas, Please see comments inline.
Pierrick > -----Message d'origine----- > De : [email protected] [mailto:[email protected]] De la part de > Konstantinos Pentikousis > Envoyé : mardi 13 novembre 2012 16:53 > À : jouni korhonen; [email protected] > Objet : Re: [DMM] comments on draft-ietf-dmm-requirements-02 > > Hi Jouni, all, > > | "PS2: Divergence from other evolutionary trends in network > | architecture > | > | Centralized mobility management can become non-optimal with > a > | flat network architecture." > | > | o What are the "other"? I would consider removing PS2 if we cannot > |name those. > > I think "other" here refers to the distributed nature of delivering > network services/content today (e.g. multiple data centers, CDNs etc.). > It's not only the mobile that moves around these days, but your > "correspondent" node as well. > Exactly. Here, we refer to distribution of content delivery, i.e. CDN. Probably, one of the main motivation for distributing mobility management :-) IMHO, if we should keep only one PS, it would be PS#2 :-) > > | "PS3: Low scalability of centralized route and mobility context > | maintenance" > | > | o Isn't e.g. the SDN evolution just doing to the opposite? Highly > | centralized management point for traffic steering? I would > > Oh dear, should we discuss SDN scalability here? :) > > > | "REQ2: Transparency to Upper Layers when needed > | > | DMM solutions MUST provide transparent mobility support > |above the IP layer when needed. Such transparency is needed, > |for.." > | > | o Doesn't the "when needed" make the earlier MUST conditional? At > |least I understand it so. If that is the case we probably could just > say: > | "DMM solutions SHOULD provide transparent mobility support above > |the IP layer." ? > > I know we should not be talking implementation, but since I got > inspired just now, this is the way I parse the former: > > procedure dmmXYZ (in: mobility_support_required, out: mobility_support) > { mobility_support = false; ... > if (mobility_support_required==true) then mobility_support=true; ... > } > > Your proposal does not capture the conditionality of mobility support > for different hosts, applications, and even different sessions of the > same app. I read it more like > > // set to 0 for disabling mobility support #define MOBILITY_SUPPORT 1 > I agree that conditional mobility support, depending on application capability, is a key requirement. However, I think that this requirement is orthogonal to the distribution of mobility management functions; actually, we may have the same requirement with centralized mobility management, right? Basically, here, we refer to the capability of an application to use either a home IP address or a local IP address, depending respectively on the need, or not, for IP session continuity. This is not really a DMM issue but a source address selection problem and the terminal (i.e. the function tackling with source address selection) must be able to distinguish between anchored address/prefix and local address/prefix to make a decision. This is why we have also suggested a work item on prefix coloring in DMM, even if the scope of prefix coloring is larger than DMM. > |In Section 4.4: > | > | o I would just remove the sentence: > | "Motivation: Using IETF protocols is easier to deploy and to > | update." IMHO it brings no additional clarity what has already > | been said. > > Second this too, although the section looks a bit too short then. > > Best Regards, > > Kostas > > > > _______________________________________________ > dmm mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/dmm _________________________________________________________________________________________________________________________ Ce message et ses pieces jointes peuvent contenir des informations confidentielles ou privilegiees et ne doivent donc pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce message par erreur, veuillez le signaler a l'expediteur et le detruire ainsi que les pieces jointes. Les messages electroniques etant susceptibles d'alteration, France Telecom - Orange decline toute responsabilite si ce message a ete altere, deforme ou falsifie. Merci. This message and its attachments may contain confidential or privileged information that may be protected by law; they should not be distributed, used or copied without authorisation. If you have received this email in error, please notify the sender and delete this message and its attachments. As emails may be altered, France Telecom - Orange is not liable for messages that have been modified, changed or falsified. Thank you. _______________________________________________ dmm mailing list [email protected] https://www.ietf.org/mailman/listinfo/dmm
