Mesh networks also called ad hoc networks communicate with each other through wireless connections. Information “hops” from one node to another without having to go through a router system. The benefits include
Self-healing – the network can route around a dead node.
Anonymous – nodes can join and leave the network at will.
Pervasive –self-healing with ability to grow the network through the addition of nodes provides for a robust network.Lower cost --
an ad hoc network is cheaper than one with a fixed infrastructure.
Some of the early applications for mesh networking will be sensor networks, consumer electronics, and fixed wireless applications. It’s nice to see the consumer electronics world making use of this technology as that segment can drive volume and demand in ways that the industrial world cannot.
City-wide wireless networks are also making use of mesh networking technology. Tropos
makes a system that uses mesh networking as the core architecture of it’s metro-wide WiFi solution which can be used to read utility meters, parking meters, and even monitor areas for crime.
The key advantage to mesh networks is that telecom companies don’t own the networks. Several new startup companies are taking advantage of this. PacketHop
is a startup that turns a set of devices into a mobile ad hoc network using 802.11 technology. With the proliferating number of mobile devices using WiFi, PacketHop hopes to leverage that installed base into an autonomous mesh network which doesn’t require an infrastructure. Another company, Firetide
also makes a play for mesh networking with its Hotspot software. Kiyon
developed a single radio platform that also leverages the installed base of WiFi devices. For those requiring high reliability there is the Strix System
which uses multi-radio, channel, and RF for high performance applications.
If you are interested in building your own mesh network system, there’s a number of Open Source options available. Check out this piece
on the O’Reilly site for options and a short tutorial on how to use one of them.
The two issues holding back the development of mesh networking is first, the unreliability of wireless links. Battery power (or the lack thereof) brings down many nodes, while the spotty coverage of wireless signals makes other nodes unusable. Second, the lack of standards holds back progress. There are efforts under way by those who promote ZigBee, but in talking with many of the adherents, they find the proposed standard full of weaknesses and most only apply portions of the standard (the portions they like) to their products.
If you are working in mesh networks, I would like to hear from you. National Instruments will be holding their annual NI Week conference in Austin next week (August 15-18). During this conference several sessions will focus on wireless sensor networks including mesh networking. If you are interested in wireless sensor technologies, I recommend you join the session on Thursday, August 18, at 1:30.
Hall T. Martin