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2008.02.18 NANOG 42 Lightning Talk Notes (First four in a batch)
I was going to do the lightning talks separately, but they all went so quickly (like lightning!) the notes rather ran together--apologies, but at least I put some ===== separators in to make it somewhat clearer. :) Matt (again apologies for typos, and now off to lunch!) 2008.02.18 Lightning talk #1 Laird Popkin, Pando networks Doug Pasko, Verizon networks P4P: ISPs and P2P DCIA, distributed computing industry association, P2P and ISPs P2P market is maturing digital content delivery is where things are heading; content people are excited about p2p as disruptive way to distribute content. BBC doing production quality P2P traffic; rapidly we're seeing huge changes, production people are seeing good HD rollout. Nascent P2P market pre 2007 Now, P2P is become a key part of the portfolio for content delivery P2P bandwidth usage cachelogic slide, a bit dated, with explosion of youtube, the ratio is sliding again the other way, but it's still high. Bandwidth battle ISPs address P2P upgrade network deploy p2p caching terminate user rate limit p2p traffic P2P countermeasures use random ports Fundamental problem; our usual models for managing traffic don't apply anymore. It's very dynamic, moves all over the place. DCIA has P4P working group, goal is to get ISPs working with the p2p community, to allow shared control of the infrastructure. Make tracking infrastructure smarter. Partnership Pando, Verizon, has a unch of other members. There's companies in the core working group, and many more observing. Goal is it design framework to allow ISPs and P2P networks to guide connectivity to optimize traffic flows, provide better performance and reduce network impact. P2P alone doesn't understand topology, and has no idea of cost models and peering relationships. So, goal is to blend business requirements together with network topology. Reduce hop count, for example. Want an industry solution to arrive before a regulatory pressure comes into play. Drive the solution to be carrier grade, rather than ad-hoc solutions. P2P applications with P4P benefits better performance, faster downloads less impact on ISPs results in fewer restrictions P4P enables more efficient delivery. CDN model (central pushes, managed locations) P2P, more chaotic, no central locations, P2P+P4P, knowledge of ISP infrastructure, can form adjacencies among local clients as much as possible. Traditional looking network management, but pushed to network layer. P4P goals share topology in a flexible, controlled way; sanitized, generalized, summarized set of information, with privacy protections in place; no customer or user information out, without security concerns. Need to be flexibile to be usable across many P2P applications and architectures (trackers, trackerless) Needs to be easy to implement, want it to be an open standard; any ISP/P2P can implement it. P4P architecture slide P2P clients talk to Ptracker to figure out who to talk to; Ptracker talks to Itracker to get guidance on which peers to connect to which; so peers get told to connect to nearby peers. It's a joint optimization problem; minimize utilization by P2P, while maximizing download performance. At the end of this, goal is customer to have a better experience; customer gets to be happier. Data exchanged in P4P; network maps go into Itracker, provides a weight matrix between locations without giving topology away. Each PID has IP 'prefix' associated with it in the matrix, has percentage weighting of how heavily people in one POP should connect to others. Ran simulations on Verizon and Telefonica networks. Zero dollars for the ISPs, using Yale modelling, shows huge reduction in hop counts, cutting down long haul drastically. Maps to direct dollar savings. Results also good for P2P, shorter download times, with 50% to 80% increases in download speeds and reductions in download time. This isn't even using caching yet. P4PWG is free to join monthly calls mailing list field test underway mission is to improve Marty Lafferty ([email protected]) Laird ([email protected]) Doug ([email protected]) Q: interface, mathematical model; why not have a model where you ask the ISP for a given prefix, and get back weighting. But the communication volume between Ptracker and Itracker was too large for that to work well; needed chatter for every client that connected. The map was moved down into the Ptracker so it can do the mapping faster as in-memory operation, even in the face of thousands of mappings per second. The architecture here is one proof of concept test; if there's better designs, please step forward and talk to the group; goal is to validate the basic idea that localizing traffic reduces traffic and improves performance. They're proving out, and then will start out the Danny Mcphereson, when you do optimization, you will end up with higher peak rates within the LAN or within the POP; p2p isn't a big part of intradomain traffic, as opposed with localized traffic, where it's 80-90% of the traffic. What verizon has seen is that huge amounts of P2P traffic is crossing peering links. What about Net Neutrality side, and what they might be contributing in terms of clue factor to that issue? It's definitely getting attention; but if they can stem the vertical line, and make it more reasonable, should help carriers manage their growth pressures better. Are they providing technical contributions to the FCC, etc.? DCIA is sending papers to the FCC, and is trying to make sure that voices are being heard on related issues as well. Q: Bill Norton, do the p2p protocols try to infer any topological data via ping tests, hop counts, etc.? Some do try; others use random peer connections; others try to reverse engineer network via traceroutes. One attempts to use cross-ISP links as much as possible, avoids internal ISP connections as much as possible. P4P is addition to existing P2P networks; so this information can be used by the network for whatever information the P2P network determines its goal is. Is there any motivation from the last-mile ISP to make them look much less attractive? It seems to actually just shift the balance, without altering the actual traffic volume; it makes it more localized, without reducing or increasing the overall level. How are they figuring on distributing this information from the Itracker to the Ptracker? Will it be via a BGP feed? If there's a central tracker, the central tracker will get the map information; for distributed P2P networks, there's no good answer yet; each peer asks Itracker for guidance, but would put heavy load on the Itracker. If everyone participates, it'll be like a global, offline IGP with anonymized data; it's definitely a challenge, but it's information sharing with a benefit. Jeff--what stops someone from getting onto a tracker box, and maybe changing the mapping to shift all traffic against one client, to DoS them? This is aimed as guidance; isn't aimed to be the absolute override. application will still have some intelligence built in. Goal will be to try to secure the data exchange and updates to some degree. ================================================================== 2008.02.18 Cable break impacts in Mideast Alin Popescu, Renesys Cable breaks 1/30/2008, mediterranean/gulf area many cables damaged Flag, SEAMEWE4, Flag-FAlcon; some severed, others had power issues 6856 networks from 23 countries affected BGP updates from 250 peering sessions with 170 unique ASes 30 Jan to 6 Feb analysis limited to outages only ignored countries with fewer than 5 prefixes (Yemen, Oman, etc.) UAE cut, Egypt cuts on map, countries with outages highlighted. Cable break 0438 hours UTC, but several events then later had outages at 0730 Feb 2nd, middle east Flag-Falcon cable in persian gulf. outages per country vs percentage; India had most prefixes, but small percentage. 1456 out of 1502, 95% prefixes had some outage. Telecom Egypt got several new providers FLAG was significantly impacted A lot of mid-level networks dropped some set of upstream connectivity, and started routing through Telecom Egypt. Prefixes over time shown, with edges involving TEgypt; shows the time series with the other big Egyptian ASes as well; they drop big global networks in favour of TEgypt. Internet is still vulnerable to disasters cost vs reliability geography plays an important role atlantic breaks happen all the time, good redundancy taiwan straits, suez canal, too much of a natural choke point Internet intelligence important to allow customers to intelligently choose new pathways or better provider diversity. Same series of outage stats through feb 17th shows that there are still some significant networks not yet recovered, even three weeks later. ======================================================== 2008.02.18 Lightning talk #3 configuration-only approach to shrinking FIBs Prof paul francis virtual aggregation single ISP without coordination can reduce size of FIB with config tricks on routers. Reduces FIB size on router, doesn't reduce RIB size on route reflectors. Status tested a couple of versions of VA by configuring on Linux and Cisco routers simple, static, small-scale experiments (~10 routers) cisco 7301 and 12000 modeled using data from a large ISP router topology and traffic matrix have not tested on a live network have not tested dynamics have not tested at large scale Cornell owns some IPR [email protected] Goal of this talk looking for some gurus to work with him on this. Would like to come up with a 'best practices' model. Goal is to partition the DFZ table among existing FIBs take address space; partition it into virtual prefixes; could be /7's, each ISP can size them as it sees fit. Assign each VA to a given router, run it as a virtual VPN each router then knows routes to all sub-prefixes within its virtual network routes to all other virtual networks. So routers follow less specific virtual aggregates to a router with more specific, which then tunnels out to the destination router. Path length can increase no so bad if there's a router covering each virtual prefix locally. border router issue problem is that border routers need full routing tables to peer with a non-participant neighbor ISPs. Routers are both L2 and L3 devices; set up route reflectors; RR peers with neighbor, does reflection to appropriate routers internally. use BGP next-hop to get routes to right place. Uses layer2 to tunnel routers through border routers. Increasing latency, increasing router load; exploits fact that there's a power line; 90% of traffic goes to 10% of destinations; put those 10% in your native tables. Requires tracking what your top 10% destinations are over time. About 15 years out is when you finally start to grow and run into the challenges with this system, based on table growth. ========================================================= 2008.02.18 Lightning talk #4 Comcast, third lightning talk of morning Alain Durand, Comcast 2nd DHCPv6 bake-off vancouver, BC, Dec 2007 Was in very bad shape last year; no off the shelf products. 8 vendors 14 implementations 6 DHCPv6 servers 5 DHCPv6 clients 3 DHCPv6 relays 15 participants 2.5 days of testing right after Vancouver IETF findings most implementations are now mature and ready for production both commercial and open source solutions available DCHPv6 clients are slowly getting integrated into operating systems Next steps 3rd DHCPv6 bake-ff in march, March 5-7th 2008 in Philly before IETF 71 DHCPv6 address assignment available on the v6-only WLAN at IETF71 Working with vendors to get DHCPv6 clients integrated in computer operating systems and home gateways. They've gone a long way in the past few years; code is getting much more solid, and finally ready for rollout. Mike, UCB; client, server working well, relay agents are the weak spots; hard to scale some of this still. Yes, relay points caused many issues during the bake off; but there is still much progress happening. Plan is to meet back here at 2pm, you're on your own for an hour. Start back at 2pm with next talk. There's a sheet floating around with places to have lunch near to the hotel. Thanks, see you in an hour.