# Wi-Fi News > Ειδήσεις - Αναδημοσίευση άρθρων >  Wireless Mesh Networks Gain Traction

## wiresounds

Πηγή: tech web

MANHASSET, N.Y. - Startup Ember Corp. will announced Monday (Nov. 17) an IEEE 802.15.4-based wireless transceiver with mesh-networking software, the third distinct boost for wireless ad hoc mesh networking in a week. Earlier, startup PacketHop Inc. unveiled a routing protocol and Zensys A/S announced a business partnership with Intel Corp.
The separate announcements bring into sharp relief the intense work now under way to achieve an efficient, scalable wireless network that is more robust than the centralized architectures now used for Wi-Fi and cellular local- and wide-area networks. They also bring to the fore a longstanding debate over a Layer 3 protocol's ability to ensure, by itself, robust connectivity for mesh networking in an RF environment. 

Derived from military-funded research into mobile networks, mesh networking eliminates the need for a central controller and its associated reliability and efficiency issues. Instead, mobile ad hoc mesh networks use peers in the network to transmit data from source to destination by means of multiple hops. 

While the Internet-like concept and its advantages are straightforward, a problem arises in deriving an optimum routing protocol to minimize the number of hops while ensuring security and seamless mobility, as well as quality-of-service (QoS). Fewer hops mean lower latency and overall power consumption. 

So far, companies like MeshNetworks Inc. (Maitland, Fla.) have dominated mobile ad hoc networking. The company's mesh-enabled architecture includes an air-interface-agnostic multihopping routing protocol and a proprietary QDMA radio. 

Ember (Boston) similarly uses a proprietary radio, the EM2420, which debuts this week. Chief technology officer Robert Poor said the chip is based on the IEEE 802.15.4 low-power physical layer and is the first device to cater to all three frequencies outlined in that standard-915 MHz, 2.4 GHz and 868 MHz, the last for Europe. This integrated transceiver has a serial interface to a variety of 8-bit host processors; the antenna interface is a simple LC network. Other features of the 0.18-micron CMOS design are hardware encryption and an on-chip Tx/Rx switch in a 7 x 7-mm package. The chip is available now, priced at $3.50 each in volume. It comes with EmberNet software, which includes libraries for mesh, star and hybrid implementations.

----------

