Introducing 802.11s - Wireless Mesh Networking

ikewillis writes "Intel has introduced a new wireless networking standard called 802.11s. This standard utilizes a mesh topology, allowing for fully self-configuring networks where each node can relay messages on behalf of others, thus increasing the range and available bandwidth with the number of nodes active within the system, versus the point-to-point structure of existing WiFi networks. This will radically transform WiFi hotspots, allowing the geographical area and available bandwidth on the network to scale with the number of participants."

s?

[Oen_Seneg]

where do they get all these letters from? There seems to be 802.11b, 802.11a, 802.11g and now 802.11s, and I have no idea why the letters are what they are. Anyone care to explain?

Wimax is LICENSED, Wifi is NOT licensed

[Cryofan]

once you get licenses in the picture, you disempower the smaller entities and empower the larger entities. And I think that most Americans are starting to see that whenever larger entities gain power over small entities and citizens, then things start to go sour...

FreeMeshWeb?

[Stanistani]

Set up enough of these, and you could do your own neighborhood network...

Could this jump-start the "freeweb" movement, particularly since the telcos are lobbying and pushing to kill the muni wireless attempts?

Let's get the entrepreneurs and the networking hippies on the same "frequency."

Re:It SOUNDS good...

[Anonymous Coward]

To promote notebooks, duh.

Imagine a free and easily accessable metro network. Not neccisarially 'the internet', but a local municipility network that is fairly unregulated and self-healing.

Network on the bus, network on the school, network at work, network everywere. You connect home, watch tv, home file servers, secure services, cpu-heavy crypto. Free VoIP. Stuff like that.

And what does Intel sell a lot of? Notebooks, cpus and chipsets and so on and so forth. What does other people sell a lot of.. Not notebooks.

This is technology that would help Intel market mobile computers in the forms of laptops and miniture devices running xscale proccessors and so forth.

Actually it's REALY FUCKING OBVIOUS what Intel would get from this. Some people.

Re:FreeMeshWeb?

[Anonymous Coward]

Free web? For who? The leaching participants? You know at some point SOMEBODY is paying for the actuall connection to the net!

Free... jeeze...

Speed

[Anonymous Coward]

This network topology is great idea in theory - but think of the possible latency issues. Wi-Fi has a long way to go before it will be able to handle the bandwidth requirements to handle a mesh-style network.
Think about the conventional wired based internet - it would never work in a similar way to this concept. That is why there are dedicated routers that take care of such tasks.

WiFi lower level protocol vs. IP

[sploxx]

There are already many research projects ongoing which try to find good routing algorithms and network topologies for IP based mesh networks.

Most of these projects try to build their mesh networks on the IP level, i.e. hardware and, IMHO even more important, medium independent.

This standard seems to work below the IP level, i.e. invisible for normal routing hardware and only usable with those "s" devices.

I wonder if this is really a good idea. Making such a standard prevents altering and improving the routing algorithms (because in the best case, they reside on some FPGA) or using mesh network topologies with, lets say, a mixed WiFi, free space optical (think house to house laser pointers :) and ethernet network. You'd need upgrades for a new routing algorithm and progress in this area will be much slower.
OTOH, maybe the network will be more stable, but one has to prove that.

Re:This is great but...

[dspisak]

I've yet to see a single piece of WiMAX gear materilaize anywhere. I'll be surprised if any of it is out by years end. WiMAX is geared towards long distance, static location hauls. You might be able to make it work as a mesh network but you would be better served by a dense mesh network so you have redundancy and multiple antennas you can recieve and send to to help with radio contention.

That's why it's a mesh

[mveloso]

The whole idea behind a mesh network is there is no single point of failure.

That does mean you have to design things so there isn't a single point of failure...unless you want a single point of failure, of course.

The spec just addresses the nuts and bolts of devices talking to each other. It doesn't take the place of an intelligent designer.

Re:Sounds great but unreliable?

[Anonymous Coward]

Isn't the idea that there would would be a mesh, rather than a string of nodes? With a mesh, the loss of a node would just result in the data circumventing that node.

Re:WiFi lower level protocol vs. IP

[Wesley Felter]

You could put IP routing in hardware or a mesh MAC protocol in software; people have done both. It's an orthogonal issue. In fact, 802.11 products seem to be moving towards having as much of the work done on the host as possible to reduce cost (think Winmodems).

Re:Wimax is LICENSED, Wifi is NOT licensed

[gid13]

Frankly, I have a certain suspicion that most Americans (perhaps even more than other nationalities) are too busy watching wrestling, praising Jesus, declaring war on abstract nouns, etc., to pay attention to whether the leader of their country is capable of rational discourse, let alone whether a particular wireless protocol is empowering large companies or not.

(Yes, I'm going for an even split between funny and troll).

Re:This is great but...

[teoryn]

I believe the idea is that each node is also hooked to the internet, or at least a good number of them. From there the pressure on any one internet connection could be reduced by distributing it to other nodes. However, even if a mesh was seperated, there would still be an internet connection for each side of the divide.

Agreed! And also...

[PaulBu]

I've read the scenarios for the wireless kind of "mesh" which assume that "all devices are created equal", regardless of if they are routers connected to the wall outlet or a (potentially on its last drops of juice) cellphones/PDAs. If such a thing really takes off you will NEVER get "stand-by" power consumption and battery life from your (constantly transmitting other people's data) cellphone.

Paul B.

Re:This is great but...

[HD Webdev]

What's the point of wireless mesh networking? By its very nature, it'll always be a broadcast network rather than a point-to-point network, so as the number of users goes up, the available bandwidth goes down. I'd think you'd want to get your connection off the air and into wires as fast as possible.

Not to mention, security. This opens up a wide-open area for Bad People to do Bad Things with much more ease.

Re:Wimax is LICENSED, Wifi is NOT licensed

[michaelggreer]

corporations have no power that isn't given to them by choices consumers make

Just a for instance [wikipedia.org]

Re:Whither the Internet?

[mattbelcher]

Theoretically, no. Gupta and Kumar showed that the per-node bandwidth in such a network decreases with O(1/sqrt(n)) where n is the number of nodes. Thus, the more nodes you have, the less bandwidth each will get. As n approaches infinity, this number becomes 0.

University communities

[Anonymous Coward]

Am I the only one that doesn't see the potential to share files across a local community network, not necessarily internet access? This standard would be amazing for University housing neighbourhoods.

This is premature

[mattbelcher]

As someone who does research in this area, I think this announcement is a little premature. There are several fundamental problems that have yet to be solved with this sort of wireless network topology, and I don't see any indication that the 802.11s task force has solved them.

For example, no one has given a MAC protocol that solves the hidden/exposed sender/receiver problems simultaneously. Without such a MAC protocol, it is impossible to resolve the contention fairly. 802.11 DCF solves hidden and exposed sender, but not receiver.

Also, Gupta and Kumar [bell-labs.com] showed that the per-node bandwidth in a wireless mesh with random node placement is O(1/sqrt(n)). This is especially bad news for the sort of nationwide wireless meshes people have been talking about here.

Finally, TCP is especially problematic [ieee-infocom.org] over multiple wireless hops. It causes self-interference which creates massive packet loss due to contention. TCP is built on the assumption that all packet loss is from congestion, but this assumption is not met by wireless contention losses.

In my own simulations, TCP's overaggression causes routing packet losses, creating spurious route breakage and even more TCP timeouts.