Last Modified: 2003-10-20
- Documenting deployment of multicast routing in the global Internet.
- Receive regular reports on the current state of the deployment of multicast technology. Create "practice and experience" documents that capture the experience of those who have deployed and are deploying various multicast technologies.
- Based on reports and other information, provide feedback to other relevant working groups.
- Develop mechanisms and procedures to aid in the transition to native multicast, where appropriate.
- Develop mechanisms and procedures for sharing operational information to aid in operation of the multicast backbones and interconnects.
This is not meant to be a protocol development Working Group.
|Done||Submit Internet-Draft on inter-provider coordination of the deployment of pruning mrouteds.|
|Done||Establish initial charter, goals, and long-term group agenda.|
|Done||Submit Internet-Draft outlining requirements for the existing MBONE infrastructure.|
|Done||Submit Internet-Draft specifying the use of administratively scoped multicast addresses.|
|Done||Begin work, with RPS WG, on extensions to RPSL to describe multicast routing policy.|
|Dec 99||Submit Internet-Draft specifying the use of native multicast where appropriate (e.g. exchange points).|
|Dec 99||Begin work on document of co-existence strategies for IPv4 multicast and IPv6 multicast.|
|Dec 99||Submit final version of RP document|
|Dec 99||Submit Internet-Draft specifying static allocations in 233/8|
|Mar 00||Submit Internet-Draft on debugging multicast problems.|
|Mar 00||Submit final version of scope zone announcement protocol (MZAP)|
|Mar 00||Submit final version of scoped address discovery protocol (SADP)|
|Mar 00||Submit I-D describing ISP multicast deployment practices|
|RFC2365||BCP||Administratively Scoped IP Multicast|
|RFC2588||I||IP Multicast and Firewalls|
|RFC2770||E||GLOP Addressing in 233/8|
|RFC2776||PS||Multicast-Scope Zone Announcement Protocol (MZAP)|
|RFC3138||I||Extended Allocations in 233/8|
|RFC3171||BCP||IANA Guidelines for IPv4 Multicast Address Assignments|
|RFC3170||I||IP Multicast Applications: Challenges and Solutions|
|RFC3180||BCP||GLOP Addressing in 233/8|
|RFC3446||I||Anycast Rendevous Point (RP) mechanism using Protocol Independent Multicast (PIM) and Multicast Source Discovery Protocol (MSDP)|
MBONED Nov 11, 2003 MSDP is finally through Cannot close the working group because there is not a MIB yet. Dave Thaler : I do not know what the current status of the MIB is. Bill Fenner is the primary owner. Bill Fenner: So, the update is that I have polled for MIB implementations. I know that Cisco has one. Looking at the evolution of the MSDP MIB and protocol, I backed the MIB down to more or less what Cisco has implemented. A couple tweaks and it should be ready for last call. Dave Meyer: Do you think we can working group last call it after the IETF. Bill Fenner: Yes. Meyer: Drafts on MSDP deployment and SSM 232 are both at the IESG waiting on last call. Bill Nickless : draft-ietf-mboned-ipv4-mcast-unusable-00.txt I ran into problems with IGMP snooping switches, because of MAC collisions. I thought these should be brought out in a document. However, I had feedback from the group suggesting The two approaches are - accept everything except those that are globally "unusable" (because of MAC collisions, because of their site local only use, etc.) - deny everything except what IANA has reserved specifically for multicast. Which should we do ? Beau Williamson : I think that there should be a big address space that is allowed, and then everything else Dave Meyer I think that this should become like unicast addresses. Never allocate anything unless it is absolutely necessary. Most people who ask for multicast addresses do not really know what they are asking for. I do not want this or any other working group to become the multicast address space routing registry. Also, there is the extended GLOP space which the IANA and a Routing Registry - we need to push this through and we need volunteers to help with this. Audience Member: I think we are heading for trouble if we block out lots of address space. Marshall Eubanks: I agree. If we do this I fear that the space blocked out will never be useable due to the inertia of the system. Also, I see need for extended GLOP address space and want to work to help get that set up. Beau Williamson: We need to make sure that we can limit what is unusable to a reasonable amount. Hugh Holbrook: For SSM snooping, these are more operational practice issue than Many companies, including my own, are going to Layer 3 snooping, where we look at IP addresses instead of MAC addresses, so we don't have the problems with MAC address. Maybe this should be a BCP or informational. Beau Williamson: I am starting to see address allocation problems inside enterprises - where they do not understand the relationship between their address usage which causes problems. I want to work on a multicast address allocation document. My goal is to put together an informational draft that explains the issues for everyone, both inside the enterprise and globally. Dave Meyer: The problem that we are facing is that people want unique addresses, and they use one they got a long time ago or just make one up. So we get requests from financial organizations for /18 in the multicast address range, which they don't need, and this is a problem. Kevin Almeroth: Does this relate to the updated 3171 ? Dave Meyer: Yes. I updated rfc3171 because there were /8's that were not being used. <Consensus was obtained to update and finish the draft as is (i.e., with narrow scoping).> ---------------------------------------------------------- Pekka Savola / Toerless Eckert Embedded RP for IPv6 - Issues Focused on PIM-SM not BiDir - it is more complex and not clear how to make it work. Hugh Holbrook : Why doesn't BiDir work ? Toerless Eckert: The problem is that the Designated Forwarder (DF) election would have to be done before you send the first packet - it needs to be pre-calculated and embedded in the group address. It is too much work to do this globally. Pekka: Open issues. SPT threshold is not addressed in current implementations. - There are security issues Sender side DOS attacks Old ASM - MSDP floods SSM - Only first hop router is flooded Embedded RP - the embedded RP is flooded No multicast state, though Receiver Side is very similar to SSM Is this critical ? Marshall Eubanks: The vulnerabilities seem similar in danger to SSM, which I think renders them acceptable. Also, if I embed your IP address (not a router, just a random address) in a embedded RP address, can't I DOS your (or any arbitrary) IP address. This is a little different from SSM, where I can only DOS your RP. Pekka: Yes. Tom Pusateri: This will require changes to RPs and elsewhere. Does a protocol change belong in an operational group ? Dave Meyer: Yes, this is an operational group, but if we see something that's needed, and its not getting done, we need to do it. ----- Toerless Eckert : We need to create an IP Multicast Address-Plan This is enforced today by manual allocation & scoping within a PIM domain. In a PIM domain, this is fine, as it sits inside an AS. With embedded RP, the PIM domain becomes bigger than an AS, so the binary discussion between inter and intra domain becomes no longer adequate. This is too simple - the inter vs intra domain decision should become a sliding scale. Dave Meyer: I have never seen a document which says how to allocate RFC1918 addresses. Why do we need one now ? Toerless Eckert: Proposal : Leave the lower 7 bits of the Group ID bit open for different service models, to be defined later. For example, a bit saying "only accept multicast data from sources in the same address block as the source" would help avoid traffic interference in few to many ASM multicasts. Lenny Guilani : If you want to do interdomain multi source does that mean that the sources DF is going to register with the RP? This is basic to any embedded RP. I just think that we need to decide how to handle the multi-domain case. Lenny Guiliani: How is anycast RP done in embedded RP ? Toerless: I took this slide out, but I do not think that this is a problem. Dave Meyer: Is it possible to merge this up into one document ? Toerless Eckert: I don't think that we should do this. What's the need to allocate all of the bits right from the start. Hugh Holbrook: It seems that this a point with minor operational issues which should be moved forward. <consensus was obtained to continue moving forward with the embedded RP proposals> ------- Lenny Guiliani: Framework for deploying IPv6 Multicast Competing idea : Just do SSM interdomain for IPv6 Intradomain - do what you want. Dave Meyer: The authors felt that since the embedded RP draft is moving forward, this draft was dead. I wanted to explore to see if this could be continued as a BCP or something similar. Lenny Guilani: We could do anything from simply deprecating ASM to saying that SSM is the long term solution. The authors favor the deprecating ASM option. Kevin Almeroth: I would say that it should say that SSM must be done. Dave Thaler: I do not want for application developers to say that "we need ASM, so we can't use IPv6." I do not want disincentives to not to use IPv6. I suggest Option 3.b, just telling people that SSM is the way to go. John Meylor: It is a moot point to a degree, as there are embedded RP solutions out there already. Maybe the market will deprecate ASM in the long run. Pekka S.: One thing that might be useful is a framework document describing when to use SSM and when to use embedded RP. Tim C: In the Op6 group there are documents on how to move applications to IPv6. Is there such a document on how you move to SSM ? Lenny Guilani: John Meylor: Is there a detailed description on how to do multisource with SSM ? Hugh Holbrook : This is missing. Dave Meyer: What we really need is a deployment document that describes functionalities we have and how to achieve them. Lenny Guiliani: Wouldn't this be a "yeah we already know that" Dave Meyer: I do not think that anyone has a done a detailed gap analysis on either side. Kevin Almeroth: Isn't SSM the lowest common denominator ? If they support any PIM, shouldn't we say that they have to support SSM ? Dave Meyer: The analysis needs to be done before we say that. Dave Meyer: I do not think that there is any consensus here, so I will take this to the list. ------- Dave Meyer: The 3171 guidelines to IANA has expired. There are 4 other drafts that have expired. I want to try and revive all of these. Dave Thaler: My draft was at the IESG waiting for approval. I can revive it easily if there is interest. ------- Hugh Holbrook - Update on the Apple IPR issue for SSM Apple claims that a patent that they own is infringed on by SSM. It says that they want reasonable and non-discriminatory licenses SSM is a core technology, so this issue cannot be fudged. This will be discussed at the SSM WG We do use a lot of IPR-impacted technology in the IETF. We need to make a risk-benefit decision before we move forward. Mike Luby: Have you talked to Apple recently ? Hugh Holbrook: I talked to Apple through the back door recently, but they were not very open to changing the wording. They point to all of the similar wording on the IETF IPR. Audience Member: When was this patent granted? Hugh Holbrook: Granted 1996 - the creator was Mark Green, who is still around. Dino F. I was working with Mark Green on this, and they would not likely view this applying to the ASM parts of PIM-SM. Kevin Almeroth: This same risk applies to pretty much everything Bill Fenner: You are only required to disclose IPR if you are working on a spec. The simple fact that Apple has come forward with this when they could have waited should not be viewed as requiring us to do anything about it. Dino F.: Apple didn't wait. We were worried that PIM was infringing, so it was brought to their attention. ------ Kevin Almeroth: We need better feedback tools. If we are not receiving traffic, we need tools to decide what is going wrong. Ideas : SSM ping - establish SSM reachability. Is there a new ICMP message needed ? What are the security issues ? The mechanism for trying multicast now - join and wait - is just not robust enough. Kamil Sarac wrote a preliminary draft. Is there interest ? Pekka S. There is a similar problem with embedded RP. There is a potential for DOS attacks Louis Lamenkis: In my previous life as an operator, there was a definite need for this. Beau Williamson: What we really need is a replacement for mtrace, which seems to be broken now. Kevin Almeroth: We also need to get feedback from first hop routers - do they support IGMPv3 ? Am I sending (S,G) in an ASM range or a (*,G) in an SSM range ? We need better feedback. There have been a lot of us who have worked on this. The tools are still really primitive. Louis Lamenkis: There are overlapping problems here. One problem I had was, "is the first hop router multicast capable" ? One size does not fit all. Dave Thaler: What are the problems with the current mtrace ? (Besides MSDP.) Bill Fenner: Are these implementation problems or protocol problems ? Dave Thaler: Before MSDP, mtrace seemed to work fine Bill Nickless: mtrace is not useful for when you have a RP with any sort of tree switching Dave Meyer: Our charter (when revised) will definitely include Marshall Eubanks: What about the various multicast beacon groups and their software tools ? Kevin Almeroth: That doesn't help application writers Marshall Eubanks: So you would put mping in an application ? Kevin Almeroth: Yes. John Meylor: Is mping the most important thing ? I would say that mtrace is. Kevin Almeroth: That's an implementation issue, not a WG issue. John Meylor: A posted draft for mtrace would be really useful. -------------------- FLUTE: Rod Walsh FLUTE == File delivery over Unidirectional Transport Based on ALC & LCT but fully specified 3 genetically different implementations now FLUTES from INRIA TUT (Tampere Finland) Nokia U. Bremen Interop testing 2 and 3 way testing - multicast and unicast working towards a 4 way test. Need a new Interoperability Testing Guideline document. RMT is likely to go dormant soon, so we need to know if we can do this in MBONED. Toerless Eckert: This is router based, right ? Are there any implementations that do the router based congestion control ? Lorenzo Vicisano There are no implementations with built in (non end to end) congestion control. Dave Meyer: I think that this is outside the scope of this working group. Tom Pusateri: I don't think that being in or out of scope of the charter is relevant to this working group! Dave Meyer: Point taken. I would be concerned about our competency to do this. Lorenzo Vicisano We will continue this in RMT. The only question was the interoperability testing. Rod Walsh: There will be a document for interoperability guidelines Mike Luby: Where will it be published ? Rod Walsh: This is open, but it sounds like it should be RMT. ------- John Meylor IMDOC Internet Multicast Documentation Problem : There tends to be holes in deployment. Some Issues - Multisource use for SSM ? or Tunnel use for initial deployment . Topics fall through the cracks, as so much is spread over various working groups. Also, build it and they will come has not worked in practice. Need : Process to track these issues across working groups draft-meyer-mboned-ipmcarch-00.txt Handle in MBONED with no extra WG needed. Dave Meyer: People have asked - is this a directorate ? This comes from the AD's. Unless and until the ADs ask for a Directorate we will do this here. If IMDOC did recognize a real gap or hole in the current work, then they could propose to the AD's that a given working group be pushed to handle it. Toerless Eckert: Couldn't this lead to protocol changes or enhancements ? Dave Meyer: IMDOC is a process. It is not our intention to write protocols - that should be left to others. John Meylor: Our goals are to 1.) write down a framework 2.) discuss input 3.) set priorities !