MEXT WG @ IETF-79 Meeting Minutes

 

Meeting minutes based on notes taken by Jouni Korhonen and Telemaco Melia.

 

MONDAY, November 8, 2010

0900-1130 Morning Session I

Valley Ballroom C        INT       mext     Mobility EXTensions for IPv6 WG

 

- Administrativia & Status Update, Chairs

 

Chairs: 3775bis is done, flow mobility is done. WG has completed rechartering with new work items.

Two voluntary reviewers for MIPv6 alternative security from Jouni Korhonen: Suresh Krishnan & Sri Gundavelli.

One voluntary reviewer for Behcet's draft on DSMIPv6 HA IPv4 address provisioning with DHCPv4: Kent Leung.

 

- Overlapping IPv4 Address Assignment Support for Dual-stack Mobile IPv6, Sri Gundavelli

     http://tools.ietf.org/html/draft-gundavelli-mext-dsmip-ipv4-overlap

 

Sri Gundavelli: Not explicitly supported in RFC5555, but implicitly required. A kind of implementation issue. Needed by e.g. 23.975 IPv6 transition scenarios.

Raj Patil:This is purely internal to the implementation, not protocol impact, why do we need to specify.

Behcet Sarikaya: no need for this. It is by design a working scenario already.

Raj Patil: what needs to be extended in DSMIP to support this?

Sri Gundavelli: have scenarios described and describe what is needed in Binding Cache Entries and what options need to be there.There is assumption that a HA gives unique addresses per MN

Raj Patil: agree on that.

Unknown: is this going to be purely informational? it does not need to any protocol impact?

Sri Gundavelli: used today already.

Hidetoshi Yokota: It is deployed today in IPv4.

 

Three voluntary reviewers: Jouni Korhonen, Raj Patil, Christian Gotare

 

- Security On Demand for Mobile IPv6 and Dual-stack Mobile IPv6, Basavaraj Patil

     http://tools.ietf.org/html/draft-bajko-mext-sod

 

Raj Patil: securing user data is optional in 3775, the choice when use security is done by MN. Makes the selection of user data protection negotiable.

Kent Leung: IKE is used for this. Why we need this for MIP level?

Julien Laganier: IKE is negotiating the security associations, not the security policy. This extension is about policy and how to update the SPD.

Kent Leung: wants a usage scenario to be detailed.

Stephano Faccin: who decides in the MN? Also in 3GPP there is no notion of trusted/untrusted networks that are based on roaming contracts.

Suresh Krishnan: draft should be more clear why IPsec mechanisms are not enough.

 

Two voluntary reviewers: Jouni Korhonen, Stefano Facin

 

- Authorizing Mobile IPv6 Binding Update with Cryptographically Generated Addresses, Julien Laganier

     http://tools.ietf.org/html/draft-laganier-mext-cga

 

Julien Laganier: Generates a HoA that is a CGA.Signs BU with the private key. HA can have repository of authz MN pub keys, or only authorize MN that are on-link at some point. No dependency on IPsec, no impact on IPsec. Allows fully decentralized HA operation (e.g. for distributed mobility management).

 

Four voluntary reviewers: Alper Yegin, Jean-Michel Combes, Sri Gundavelli, Jouni Korhonen

 

- 3GPP TFT Reference for Flow Binding, Mohana Jeyatharan

     http://tools.ietf.org/html/draft-jeyatharan-mext-flow-tftemp-reference

 

Julien Laganier: First, this is only useful in 3GPP so there’s no reason to do it in IETF. 3GPP has Vendor Specific option and they can do the work if they wishes. Second, in 3GPP TFTs are only used for QoS, so you’d still need the MEXT specified traffic selector for traffic not subject to TFTs. Thus is not worth the trouble to save 1 byte in corner cases.

 

No real support.

 

- NAT64 for Dual Stack Mobile IPv6, Behcet Sarikaya

     http://tools.ietf.org/id/draft-sarikaya-behave-mext-nat64-dsmip

 

Various: Problem description in the draft is unclear.

 

- Extensions needed for MIPv6 to resolve 4G wireless gaps, Charles Perkins

 

Charlie Perkins: 3GPP just did not select Mobile IP.. maybe 4G networking will. One proposal is allow GTP as a tunneling protocol, another is to allow for Foreign Agent in MIPv6. Another is to specify different tunnel endpoint for Home Agent, etc.

Kent Leung: how to deal with roaming?

Charlie Perkins: It’s a different topic.

Unknown: 3GPP arch already supports SGW/PGW collocation.

 

THURSDAY, November 11, 2010

1740-1940  Afternoon Session III

Valley Ballroom C       INT      mext           Mobility EXTensions for IPv6 WG

 

- Agenda Bashing, Marcelo Bagnulo and Julien Laganier

 

Hui Deng: Are we defining the PS or the solution? DMM is already in the charter? I have issues with the point in the agenda about the solution

Marcelo Bagnulo: we want to discuss how current protocols can solve some of the issues presented in the problem statement.

Hui Deng: I do not understand the agenda. It’s solution space.

Marcelo Bagnulo: shall we move to the technical discussion or continue to chat about the agenda? We are not doing solutions.

Rajeev Koodli: we are discussing about the problem statement before we go to the solution, right?

Marcelo Bagnulo: Yes

 

- Problem statement for distributed and dynamic mobility management, Dapeng Liu

     http://tools.ietf.org/html/draft-chan-distributed-mobility-ps

 

Rajeev Koodli: what do you mean by mobility? I fail to see to the problem statement.

Julien Laganier: let's go through the presentation and keep the questions for the end

Parviz Yegani: what is the L-GW in this picture? Is this the L-GW defined in the EPC?

Dapeng Liu: this is the local GW that we want to deploy; this is the function that we want to distribute

Parviz Yegani: are you trying to describe a traffic offload protocol?

Marcelo Bagnulo: let me provide some guidance at this point, what we are trying to do is present a problem. It's not clear at this stage if with the current protocols that we have could solve the problem presented here

Telemaco Melia: Dapeng's point is that there are already some deployment scenarios considering local anchoring

Kent Leung: I do not see the problem statement very well

Marcelo Bagnulo: this is the discussion that I want to have later

Raj Patil: when you have mobility all traffic is routed through the home, this is not necessarily the case as in route optimization, what is the mobility model that you have in mind?

Marcelo: please let’s have the questions at the end, let me do my job, let me go through the presentation, else the we risk to not stick to the agenda

 

- Use case scenarios for Distributed Mobility Management, Hidetoshi Yokota

     http://tools.ietf.org/html/draft-yokota-dmm-scenario

 

- Global HAHA solution, Ryuji Wakikawa

 

- Distributed Mobility Management with Proxy Mobile IPv6, Julien Laganier

 

- End of the presentations and Discussion

 

Microphone to the chairs and opening the floor for questions

 

Marcelo Bagnulo: what do you think about these problems? Do you think they need to be addressed?

Behcet Sarikaya: clarification question to Julien, in 3GPP where would be your HA?

Julien Laganier: you could map this to 3GPP if you want but let's not discuss 3GPP specific

Sri Gundavelli: clarifying question, what is the impact of this proposal on legal intercept, charging and accounting. Can you clarify?

Marcelo Bagnulo: what is the goal of your question?

Sri Gundavelli: we need to understand the impact on other services.

Hidetoshi Yokota: are you talking about the control function?

Sri Gundavelli: How you are going to perform billing for instance?

Hidetoshi Yokota: if the mobile network allows for distribution then we can distribute the function and other services will be adapted to meet the requirement

Hui Deng: if you want to do billing/lawful interception, then you don’t need to do breakout, you could continue to go through mobile core network, this is what 3GPP SA1 specified already

Christian Gotare: I am missing some points, we need to account for the number of handoffs, the residency of the MN in a cell, etc…

Marcelo: are you asking data about MN distribution?

Christian: we need to discuss how people move, how this has an impact on the distribution?

Parviz Yegani: we need to be positive about what is happening here, the anchor points have to be located close where the MN are located, this new architecture has merits but we need to check if there is merit to develop solutions in the IETF, if there is a need for low level latency we need to understand this

Serge ?: this is problem is very interesting, service providers are looking at this, and this is justified by the LIPA SIPTO work

Jari Arkko: this has an impact on the legal interception; it is an implication that needs to be taken into account

Sri Gundavelli: can we simply assume that we are going to introduce another level of complexity and cost?

Jari Arkko: need to identify the right tradeoffs about costs

Suresh Krishnan: the closer you put the anchor to the MN the more handoff happens and as such signalling increase, we need to find the right balance

Parviz: the services are not equal, some services might not require seamless mobility, they are in the bottom part of the value chain

Sri Gundavelli: what are the missing functions to answer to the problem statement?

Hidetoshi Yokota: we do not talk about protocols in the presentation.

Sri gundavelli: to support this architecture what are the extensions required?

Jari Arkko: we do not have an answer. We need to look at use cases and then at the existing protocols, it maybe sufficient it may not

Sri Gundavelli: ok you are looking at understanding

Rajeev Koodli: you are mostly looking at deployment choices, control data plane separation, we did look at local routing, what might seem reasonable is taxonomy of what the choices are, this is system design not protocol design, the industry should choose the right tool box

Suresh Krishnan: first we need to understand the problem, then we look at the protocol semantics, we need to watch out for the changes, but first of all agree on the problems

Raj Patil: good to see a sort of scenarios and pain points that have been presented, it is very useful, the reason why they bring this up is a matter of costs, the scenarios are useful, the point of DMM is not yet clear though, it is also a fact that mobile operators are deploying local anchors because there is a benefit, operational costs is another key point to consider, rather than talking about PMIP or MIP I would prefer to look at the problem as a whole, way to early about solutions

Charlie Perkins: agree on what Raj said, it is critical to understand what can be done today with existing solutions: once we do this, we will know what part/extensions belong to the network and which part to the mobile, after this we will be able to identify which part of the solutions will solve what

Hidetoshi Yokota: if CN talks for the first time, it has to find to which mobility anchor to talk to

Christian Gotare: comment about physical realization; how many people; how many stations, etc

Jari Arkko: answer about what Suresh said, I think he is right, I think that new code might be needed on the mobile node, monitoring to decide which address is used

Ahmad Muhanna: probably what we are missing is an algorithm to dynamically assign an anchor

Telemaco Melia: it’s true services are not equal, some need to be seamless; some others not: as a company are looking at an interface between applications and the network; that’s why we introduced the dynamic feature

Ruji Wakikawa: I need more pictures about the network environment, I need to know about user mobility, we want to optimize path but we need to know how fast the user is moving since we could end up with a longer path

Rajeev Koodli: distribution of mobility anchors, let's folk decide how do they want to deploy the network, I do not see on what protocol we need to work, what we need to resolve other than understanding

Hong Liu: 3GPP is specifying SIPTO, here is just copy what they are specified, and used in IP mobility

Jari Arkko: can we get the list of problems that 3GPP came up with? It is important to understand the contexts as well.

Hui Deng:  3GPP SA1 has requirement for SIPTO, which could be used here for reference.

Gaetan Feige: we should look at the type of service and users other than simply distribution of the mobility management, traffic characterization is important

Hui Deng: yes, the traffic pattern is different from mobile Macro station before. HNB or enterprise HNB could have different traffic pattern, and for SIPTO case, there are also different traffic pattern.

 

End of the discussion – microphone again to the chairs

 

The following questions have been asked to the room:

- are people interested in this work and to define the problem? (nobody did oppose)

- are people interested in looking at if current technologies are sufficient to solve the problem? (nobody did oppose)

 

Jari Arkko: given the positive feedback of the audience, first we identify the problem then understand if current solutions are sufficient. Documents will be produced to reflect this decision.