Hello

Welcome to another issue of RAD at a Glance, the newsletter from RAD Data Communications about developments in the communications industry.

ACCESS TRENDS

Fixed Wireless Finds Ample Airspace in 5 GHz Spectrum

The main motivations for using a wireless link are saving the high cost of leasing lines from a service provider, fast deployment and lack of landline infrastructure. In some cases, wireless is used to back up terrestrial lines in cases where they are not stable.

Most wireless links require a license from the national telecommunications regulatory authority, to transmit at a particular frequency. Due to popular demand, many countries have opened up license-exempt frequencies, which anyone is free to use as long as the vendor's equipment complies with the technical specifications defined by each particular country's regulatory body. The most popular frequency for license-free fixed wireless communications is the 2.4 GHz band, which has enjoyed license exemption in many countries since 1985.

Success breeds its own problems, however, and the 2.4 GHz spectrum is now suffering from overcrowding, adversely affecting the quality of communications for many users in densely populated transmission areas.

To resolve the issue of overcrowding, many countries are in the process of opening up the 5 GHz band for unlicensed broadband wireless transmissions. The band is divided into several ranges. The low bands (5.15-5.35 GHz) are reserved for in-building applications, Band B (5.475-5.72 GHz) for indoor and outdoor applications, including wireless LAN, and the high bands (5.725-5.825 GHz) are intended for outdoor applications.

Diverse Voice and Data Applications
Unlicensed fixed wireless radio is a perfect solution for point-to-point applications that call for rapid deployment or a temporary hookup, especially in areas where wireline links are expensive or scarce. Common applications for license-free fixed wireless include linking rural sites, campus network extension, backup links and disaster recovery. It is also well suited to cellular operators and service providers in rural areas (where interference is not likely) as well as to temporary sites such as army camps, construction sites and mines.

AirMux - The Hybrid Solution
There are two main approaches adopted by vendors in the license-free market: the "wireless bridge" approach and the "hybrid" approach. Wireless bridges are all-Ethernet devices, supporting LAN and VoIP traffic only. Wireless bridges do not support leased line services, which are still very common. Hybrid devices, on the other hand, support both Ethernet and TDM, enabling delivery of LAN and PBX traffic, which are the most common needs of many wireless users.

RAD's new AirMux wireless point-to-point multiplexer is a hybrid device that supports Ethernet as well as TDM circuits, especially voice. It integrates voice and data, combining n x 64 kbps, E1/T1 and Ethernet traffic over a 2.6 Mbps full duplex wireless link, extending data and voice transmissions up to 16 km (10 miles). It thereby provides a complete connectivity solution for PBX and LAN traffic. Unlike many other hybrid solutions that offer a serial data interfaces that can connect to a router, the AirMux features a LAN interface for simple, direct connectivity to the LAN.

AirMux implements time division duplex (TDD) technology, for 2-way transmission (transmit and receive) over a single channel, for a total requirement of 10 MHz channel space. This lets AirMux to provide 12 operating channels (versus 3-4 channels offered by most other vendors), enabling the user to more easily locate a free channel. The narrow channel requirement of AirMux not only helps avoid interference but also greatly simplifies installation. Its integrated radio and antenna also eases installation.

AirMux is suitable for campus and building connectivity, cellular backhaul and backup applications and at temporary sites.
More information about AirMux

GENERAL NEWS

RAD at CeBIT

This year at CeBIT, held March 12-19 in Hannover, Germany, RAD presented innovative, new products in the areas of DSL over fiber, voice compression over IP, TDM over IP (TDMoIP), Ethernet access and wireless technologies. The new products offer a migration path to next generation networks. More details

RAD Participates in 3GSM World Congress

RAD participated in the 3GSM World Congress, the world's biggest event in the GSM arena, held February 18-21 in Cannes, thereby demonstrating our commitment to the cellular market. We presented our cellular backhaul solutions, including reducing cellular transport costs as well as 2G-3G migration and co-location. Our applications generated interest among mobile operators, ranging from incumbent operators and emerging new operators ("greenfields"). Our presence at the event also enabled us to make further inroads in cooperative ventures with mobile vendors.

RAD Data Communications Demonstrates Industry's First Public Showing of E1 Leased Line over MPLS

At the MPLS World Congress 2003 Public Interoperability Event in Paris, held February 5-7, RAD's IPmux TDMoIP gateway participated in the world's first live showing of an emulated end-to-end E1 leased line over an MPLS backbone. The multi-vendor interoperability event, organized by the MPLS Forum and the European Advanced Network Testing Center (EANTC), in cooperation with the ETSI Interoperability Services and hosted by Upper Side, showcased MPLS equipment interoperability, and, in particular, network scalability and fast rerouting (under 50 ms). More than a dozen equipment manufacturers participated. Full story

SUCCESS STORIES

New York Lottery Selects RAD's Miniature Modem Sharing Devices

RAD's MMS modem sharing device enables two lottery machines to send transmissions over the same modem, enabling the Lottery to increase sales while minimizing expenses. Full story

RAD's DXC Backs Up the Wireless Local Loop

Vesper is the largest wireless local loop (WLL) operator in Brazil, providing competitive local and long distance services in Sao Paulo, Rio de Janeiro and other states. To ensure continuous operation, Vesper installed a backup network based on RAD's compact DXC-8R multiservice access node. Full story

NEW PRODUCTS

RAD's VDSL Modem Drives Data Rates up to 10 Mbps

RAD's ASM-60 4-wire, symmetrical VDSL-based modem achieves greater range than other VSDL products on the market. With selective data rates of 4, 6 and 10 Mbps, it meets the demand for increased bandwidth in the Local Loop and the corporate campus environment. Full story

WHAT'S NEW ON-LINE

SHDSL Solutions

RAD has incorporated SHDSL technology into a wide range of products for TDM- and ATM-based networks, allowing you to plan your SHDSL network with greater flexibility. Our diverse solutions are presented in our new SHDSL brochure.

Industry Insights

Don't forget to read this month's column by technology editor John Williamson.

Sincerely,
Shari Ingerman
Senior Editor, RAD Data Communications