Slashdot Mirror
A New Way to Look at Networking
Van Jacobson gave a Google Tech Talk on some of his ideas of how a modern, global network could work more effectively, and with more trust in the data which changes many hands on its journey to its final destination.
Watch the talk on Google's site
The man is very smart and his ideas are fascinating. He has the experience and knowledge to see the big picture and what can be done to solve some of the new problems we have. He starts with the beginning of the phone networks and then goes on to briefly explain the origins of the ARPAnet and its evolution into the Internet we use today.
He explains the problems that were faced while using the phone networks for data, and how they were solved by realizing that a new problem had risen and needed a new, different solution. He then goes to explain how the Internet has changed significantly from the time it started off in research centres, schools, and government offices into what it is today (lots of identical bytes being redundantly pushed to many consumers, where broadcast would be more appropriate and efficient).
8 months old?! Shame. I guess that most of the information about the history of the telephone network is out-of-date already.
I'll probably be modded down for this...
How is this anything new? Everything in that summary was already covered by Tanenbaum in his excellent book on networks - of course it's easier to hear it from someone if you're too lazy to read :p
I have spoken'eth.
There is no reason you can't multicast across a large segmented network, i.e. the internet, and get good delivery. Radio, television, audio, phone, movies are all latency sensitive but not particularly bit sensitive so you can drop some packets here and there. That also means that some things would need QoS (VoIP) while others would need intelligent caching and buffering (movies, etc.).
[RIAA] says its concern is artists. That's true, in just the sense that a cattle rancher is concerned about its cattle.
"(lots of identical bytes being redundantly pushed to many consumers, where broadcast would be more appropriate and efficient)"
The first part is true, but does not necessarily lead to the conclusion in the second. There is a huge, very important IF that belongs between them. Specifically, "if the recipients are all prepared to receive those bytes at the same time". The problem with the conclusion is that the evaluation of the "if" part is nearly always "they're not". This is yet another case of "if the internet were like television, it'd be more efficient". Yes, but it would then no longer be the internet people like. The great promise of the internet is information on demand. All this bullcrap about broadcast, push, and the like, it's all the efforts of 20th century throwbacks trying to fit the internet into their outdated worldview of "producers" and "consumers". They need to quit it. Broadcast is a square peg and the internet is a round hole. Every time anyone suggests putting the two together, they simply look like a bloody idiot.
If a job's not worth doing, it's not worth doing right.
I 'browsed' some of this video and book marked it for later: Van Jacobson's background is awesome.
A bit off topic, but there are two things that I want to see happen: a complete upgrade to IPv6 and the creation of an alternative 'public Internet' based on emerging long distance wifi and software that lets people volunteer to be part of this new open grid, and optionally share some bandwidth bridging the 'real' Internet.
It may seem pointless to want both higher performance (multi-casting UDP, essentially infinite IP address space) and low performance and ad-hoc systems, but please consider: the UK and USA seem to be going down the wrong path of surveillance and citizen control, the Internet may someday be viewed as something that the public just should not have because it is too free a source of information. I hope that I am wrong about this, but this unpleasant possible repressive future is a possibility.
Based on all the measurements I'm aware of, Linux has the fastest & most complete stack of any OS (source)
So, sending identical packets to everyone is somehow more bandwidth efficient than sending packets to only those who want them? Doesn't that seem backwards to anyone else? Furthermore, couldn't you define broadcasting as precisely the act of sending identical bytes to many consumers?! I'm teh confused.
TLF
I do not respond to cowards. Especially anonymous ones.
- Only people actively downloading or seeding content are available to redistribute it, so there's a built-in time-dependence which makes in unsuitable for small pieces of data.
- It has no knowledge of topology, so it can't take advantage of topology to cache data closer to endpoints.
I wish someone had asked about freenet, since that seems much closer to what he describes."If you look 'round the table and can't tell who the sucker is, it's you." -- Quiz Show
I enjoyed this talk very much. It was more than just a statement of Van Jacobson's thoughts on data dissemination. It showed his analysis of the relationship between infrastructure and application across two generations of networking, and it pointed out very nicely why it's time now for phase 3: we've moved our usage goalposts compared to when the IP network was designed. Great stuff, and I agree completely.
:-)
:-)
The article submitter didn't seem to "get" what Van Jacobson was saying though, as the talk had almost nothing to do with broadcasting or multicasting. Indeed, Van Jacobson actually pointed out why multicasting and broadcasting were inappropriate in most situations in this new world (they carry implicit time sync), so only use them as accelerators on LANs or in other special cases. The slightly wrong article description may have misdirected some of the posts here since not everybody reads TFA, and even fewer sit through an extended talk. It wasn't about broadcast or multicast at all, except in passing.
Maybe it'll help to summarize his thrust briefly.
What he said was that the network underneath doesn't actually matter, and that the wires and fibre underneath don't actually matter either -- TCP/IP has abstracted away from them. However, the client-server model on which TCP/IP is based is no longer strictly relevant either, because it is founded on a somewhat obsolete concept, the "conversation". The vast bulk of our Internet traffic is no longer "conversations", but "data dissemination" (the migration of identified data objects from place to place), and actual conversations are just a special case of that.
Data dissemination is utterly different to conversation as a communications paradigm, and that's what he's getting at. Fully identified, self-validating items of data as discrete entities are really where our focus needs to be, and how they get to us is rather immaterial, or abstracted away. *Where* they come from (ie. the actual server to which we connect) is quite immaterial too --- getting it from a passing plane would be as good as from a known server, when you can rely on data identity. Furthermore, if the data items were fully self-descriptive then many of the current problems like spam would go away as well. What's more, the nodes of the network would be able to work more intelligently too (and hence efficiently), if they were aware of data identity rather than just treat everything as a conversation.
That's a very brief summary and can't hope to do the talk justice. Go listen! He's dead right.
"The question of whether machines can think is no more interesting than [] whether submarines can swim" - Dijkstra
You give a pretty good short summary of a long and interesting talk.
One thing I pulled most out of it was the analogy to 60s and 70s networking and how it is only after technology has been adopted that we see what its used for.
When the telephone was invented Bell didn't know what it would be used for, its a strange concept but he really didn't know what a "phone call" was. He just knew he could transmit voice. Not only that but you had to have wires to connect people, so there was this very expensive business of putting wires everywhere. What happened was that people used those wires to make conversations. To establish a conversation you had to have a path between two nodes. This encouraged a monopoly because the best known way to make paths was to have control of all the wires.
When the idea of what TCP/IP was to become was introduced people thought it was lunacy. What they were proposing was adding all this crap onto your data to explicitly name your destination so that it could travel any path to get to its conversation partner. All the networking researchers didn't get it because they already had implicit addresses by way of making the path. Turns out that the supposed innefficiency solved several problems simply by construction. Being able to take any path meant not caring about the underlying topology.
What Van Jacobsen is proposing is another abstraction. Essentially adding another layer of "crap" that will allow us to ignore the underlying network. He mentions how several technologies are working towards these ends to some degree like bittorrent and akami CDN, but I think he is advocating for something like a new protocol. This new protocol would then end up solving some of our current problems simply by construction. Broadcast and one-to-one will become the same thing. Whether you are sending a secure email (pgp signed and named) or downloading the front page of the nytimes you could rely on the nature of the new protocol to deliver you authentic data, no matter where it comes from.
Personally I think its genius, I'd like to follow the progress of such a protocol if it exists. I just got done watching the talk so I'll be googling around for a little I suppose.
"how can they call it a MINE if everything here is THEIRS?!?!" -Straight Jacket
...but the more he talked, the more it reminded me of some halfbreed between akamai and freenet.
Basicly, he's speaking of named resources, that an URL would be key like KSKs in Freenet
Content would self-verify, that's basicly CHKs in Freenet
Then you need add security into it which pretty much amount to SSKs
Only in his case, it wasn't talk about making the end nodes treat information this way but rather the core of internet, and it didn't involve anonymity. But the general idea was the same, to grab content from a persistant swarm of hosts who doesn't need a connection to the original source. Unfortunately, most of the examples he gives are simply false, like the NY Times front page. If I want up-to-the-minute news everybody need to pull fresh copies off the original source all the time, reducing it down to a caching proxy. Any sort of user-specifc content, or interactive content won't work. For example take slashdot. I've got my reading preferences set up, which means my content isn't the same as yours. Also my front page contains a link to my home page, which is not the same as yours. Getting a posting form and making a comment wouldn't be possible. Making any kind of feedback like digg, youtube, article feedback etc. isn't possible. Counters wouldn't be possible. The only thing where it'd work is reasonably static fire-and-forget content, and even then there's the problem of knowing what junk to keep. Notice that when asked about BT he said that only worked for big files, so the idea is that everyone will have some datastore where they keep small files until someone needs them. The only good example is the Olympic broadcast, which is exactly the same content at exactly the same time. Oh wait, that's classic broadcast. Classic broadcast works best in a broadcast model? Who'd think that.
Live today, because you never know what tomorrow brings
I see one problem with his idea of ignoring where data comes from.
Corporations make money by restricting access to information.
It doesn't seem that it will be possible for them to continue to do that with this model, so I don't think any of this will come to pass any time in the near future.
I thought I was going to skim through that video when I first saw it a while ago.
Then I started watching, and at some point noticed I watched the whole thing, without skipping anything.
I think he gives a good talk, and it kept me interested the whole way.
Its a very nice insight he has there, too bad it flies way over Slashdotters head (well, its just that almost all of them probably didn't even read the whole thing).
By the way, I summarized his ideas (as I understood them, which may not be the same as he explained them).
8 months seems pretty new to me. I notice that many of our discussions seem to focus on 1984. Wake up people! A lot has happened since then, and now it's a brave new world.
testing out my trending skills