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Enhancement To P2P Cuts Network Costs 190

psycho12345 sends in an article in News.com on a study, sponsored by Verizon and Yale, finding that if P2P software is written more 'intelligently' (by localizing requests), the effect of bandwidth hogging is vastly reduced. According to the study, redoing the P2P into what they call P4P can reduce the number of 'hops' by an average of 400%. With localized P4P, less of the sharing occurs over large distances, instead making requests of nearby clients (geographically). The NYTimes covers the development from the practical standpoint of Verizon's agreement with P2P company Pando Networks, which will be involved in distributing NBC television shows next month. So the network efficiencies will accrue to legal P2P content, not to downloads from The Pirate Bay.
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Enhancement To P2P Cuts Network Costs

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  • 400%? (Score:5, Insightful)

    by Sam H ( 3979 ) <sam@zoy.org> on Friday March 14, 2008 @10:23AM (#22750764) Homepage
    How do you reduce the number of 'hops' by an average of 400%? Negative number of hops? Also, FP.
  • Re:P2P - P4P? (Score:5, Insightful)

    by TripMaster Monkey ( 862126 ) on Friday March 14, 2008 @10:26AM (#22750788)
    Well, strictly speaking, incrementing the number would result in P3P, not P4P. Just as P2P means "Peer to Peer", P4P could be interpreted as "Peer for Peer", justifying the numeral.
  • by Dr.Merkwurdigeliebe ( 1055918 ) on Friday March 14, 2008 @10:27AM (#22750796) Homepage
    ... or is it encouraging to see network providers taking a stance other than p2p is bad? This looks good - kind of like "p2p isn't going away, so as long as we have to live with it, let's try to make the best of it"
  • by n3tcat ( 664243 ) on Friday March 14, 2008 @10:37AM (#22750872)
    While I understand what they're saying here, and I understand the surface intent of the message, I get this feeling that there is some sort of devious underlying motive here. Or it could just be that I have my Slashd^H^H^H^Htinfoil hat on a bit too tight.
  • Re:400%? (Score:5, Insightful)

    by SatanicPuppy ( 611928 ) * <Satanicpuppy.gmail@com> on Friday March 14, 2008 @10:42AM (#22750924) Journal
    Just typical market speak. 400% sounds sexier than "a factor of four".

    The problem that leaps to my mind is that either you're going to have to collect a huge chunk of routing information so your client can figure out which peers are "close" to you, or a third party is going to have to manage the peering...Neither one of those thrills me, especially since an ISP is pushing the technology, which would make them the obvious third party.
  • by Opportunist ( 166417 ) on Friday March 14, 2008 @10:47AM (#22750964)
    And let's face it, people, the next protocol will have to have a few features to be accepted, and having "local peers" isn't on the top of the list.

    What the list includes? Easy:

    1. Encryption
    2. Onion routing

    For very obvious reasons. And neither of them decreases bandwidth used. Quite the opposite.
  • Re:400%? (Score:5, Insightful)

    by ThreeGigs ( 239452 ) on Friday March 14, 2008 @10:58AM (#22751074)
    It gets worse. From RTFA:

    "Using the P4P protocol, those same files took an average of 0.89 hops"

    How do you possibly get an average of LESS than one hop, unless you're getting the file from yourself?
  • Re:So.... (Score:2, Insightful)

    by tech_guru5182 ( 577981 ) on Friday March 14, 2008 @11:10AM (#22751204)
    Protocol. Pirate Bay will be a torrent, their "P4P" client will use a different protocol. Now, I don't see why someone couldn't write a bittorrent client that would do the same thing (seek relatively local ips from a tracker). It is public knowledge (or at least readily available) what ISP an IP belongs to, and what country it is in. In some cases, it can be readily localized even further. (large ISPs typically will have local identifiers for the hostname of their router. For example they may use something like Springrield1.state.bigisp.com.) I don't see that this must be in the protocol to be implemented, it should be able to be done in the client as well. Perhaps it would be best if a client would look to stay first within the same IP block, then the same domain. It won't be quite as effective without knowing all link bandwidths, but would drastically improve the current situation.
  • by Animats ( 122034 ) on Friday March 14, 2008 @12:13PM (#22751960) Homepage

    This has been my main criticism of "p2p" user-level networking for years. The selection of "peers" has no clue about network structure. The routing performance is just awful. Finally, someone is doing something about it.

    One problem is that, from an endpoint perspective, it's tough to extract network topology and bandwidth. Hop count is only moderately useful. But there are a few tricks one can use.

    There are several basic numbers of interest - bandwidth, delay ("lag"), hops,"bottleneck points" and commercial boundary crossings. Each of these can be measured.

    Delay, or lag, is the easiest to measure. A few pings and you've got it.

    With bittorrent, you're not committed to staying with a peer for an entire download. So you can observe the bandwidth of the peers you're talking to and preferentially use the higher bandwidth ones. You really have to transmit for a while to get a solid bandwidth number, especially since Comcast introduced "Boost" quality of service, which increases bandwidth allocation for a few seconds on demand, then reduces it.

    If you do a traceroute, you'll usually observe that many hops show low lag (those are usually hops within a single data center) while others show higher lag. The number of high-lag hops is the number of "bottleneck points" in the path.

    Commercial boundary crossings occur then packets cross from one ISP to another at a peering point. Users don't notice this much, but carriers are very interested in minimizing that traffic. Converting IP addresses to autonomous system numbers, as someone mentioned, can tell you when you're crossing a boundary.

    So it's possible to collect enough data to do intelligent routing without much help from the network provider. What to do with that data is a separate question, but a solveable one.

  • by goombah99 ( 560566 ) on Friday March 14, 2008 @12:22PM (#22752028)
    2P or not 2P that is the question.

    THis may turn out to be a classic economics case of the tragedy of the commons.

    let's say that if I use P4P that the total path length (i.e. measured in router hops, or cable value, not distance) traversed by my data is less thereby not utilizing as much network resources. However suppose that by voluntarily restricting myself to nearby peers that my download time increases by a factor of 50% (just to make something up). Personally it costs me no more if I use P2P while everyone else is volunteering to use p4p. I'll get my downloads 50% faster and the heck with everyone else.

    Of course if everyone did that then, more network resources are consumed than neccessary, the costs of my ISP rise and my downloads are slower.

    But as an individual, if everyone else is obeying p4p I have an incentive to selfishly use p2p.

    Thus the corporate pay-networks that can actively manage peering altruism and force users to obey to resptrict themsleves to local peers over remote peers can pull this off. They can prevent defections and get better netowrk utilization and possibly even better average performance to boot.

    Whereas on voluntary networks p2p may be harder to enforce locality. It would have to be a new bit-torrent protocol in which peers would shun or share less often any nodes with long ping times.
  • 0.89 hops (Score:3, Insightful)

    by chiasmus1 ( 654565 ) on Friday March 14, 2008 @12:39PM (#22752222) Homepage
    How do you possibly get an average of LESS than one hop, unless you're getting the file from yourself?

    Usually when people are talking about hops, they are referring to routers. The only way you would not go through a router is if you and the source were in the same LAN. If you get an IP address from your ISP and it is one of the private ones (ie. then you will likely have to go through a NAT machine before you will be able to see anyone. If your IP address is a publicly route-able address then it will most likely be in a LAN with your neighbors. There are ways to explain why 0.89 would be possible.

    Claiming 0.89 hops is more interesting because they are claiming that others in your network are already downloading or have downloaded the file. It seems unlikely that someone in my own network would be downloading the same file, or would be seeding the file that I wanted. It seems to me that the most likely way that they could get 0.89 hops is by limiting the number of actual files distributed by their P4P software. Maybe they just had 10+ test files that just happened to be all over the network already.
  • by budgenator ( 254554 ) on Friday March 14, 2008 @03:59PM (#22754268) Journal
    This is a wet dream come true for verizon, not only can they advertise unlimited broadband FiOS at 40MB/s, they can deliver it without much expensive out-of-network traffic! Comcast is so screwed, blued and tatooed; even with the next generation DOCSIS 3.0 they'll have to add nodes like there is no tomorrow just to tread water!
  • by twitter ( 104583 ) * on Friday March 14, 2008 @04:12PM (#22754444) Homepage Journal

    No, it's pay for play, the way they want the internet to look. This is, of course, the opposite of net neutrality. Insultinly enough, it makes you use your equipment as part of their service. Only "secure" platforms will be allowed the privilege because it will require DRM. Expect P4P to look just like pay per view TV and P2P to see further interference. Without better regulatory oversight or a liberated spectrum, network freedom and software freedom are doomed.

To write good code is a worthy challenge, and a source of civilized delight. -- stolen and paraphrased from William Safire