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."

Comments

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...

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).

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."

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 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 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.