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Networking Standards Are Advancing

6/11/2001 02:00:00 AM Eastern

Wireless and no-new-wires home network technologies advanced in recent weeks, with the HomeRF Working Group ratifying its speedier 10Mbps 2.0 specification and the HomePlug Powerline Alliance completing field trials of its 10Mbps-14Mbps power line technology.

On top of that, the Wireless Ethernet Compatibility Alliance (WECA) announced that a proposed FCC rule could lead to 54Mbps 802.11g wireless networking products as soon as the first or second quarters of next year (see story, p. 17). WECA also said it expanded certification of 11Mbps 802.11b wireless products to 112 products from 91.

The new HomeRF 2.0 standard increases HomeRF's data rate by more than sixfold to 10Mbps from 1.6Mbps, delivering an effective throughput, or payload, of 4-6Mbps. The higher data rate will make it possible for the 2.4GHz frequency-hopping technology to migrate from home PC networking applications to home A/V networking, the group said.

The first products incorporating HomeRF 2.0 will be out in volume in late summer, said group chairman Ken Haase.

The new HomeRF spec is possible because the FCC last year approved the group's proposal to use frequency-hopping spread-spectrum transmitters to hop around in 5MHz-wide channels, up from 1MHz in the previous spec.

In May, the group publicly demonstrated 2.0 technology for the first time during two trade shows, where the group stressed HomeRF is the only home-network standard (wired or wireless) to support toll-quality cordless-phone service. That's because the standard automatically dedicates 100Kbps of bandwidth to a Home RF cordless phone as soon as the phone is in use. HomeRF incorporates Europe's DECT (Digitally Enhanced Cordless Telephony) standard for cordless phone use.

Other wireless standards implement Quality of Service (QoS) measures to prioritize multimedia streams and voice-over-IP over other data streams to prevent dropouts, Haase said, but even then, voice calls are "prioritized along with other devices, so they are still contending for bandwidth" with other devices, Haase said.

The first 2.0 products will appear at the same prices as products incorporating the lower bandwidth spec. "PC Cards and USB adapters are available today at $99, and we expect the same prices on the second-generation [2.0] products," he said.

The first 2.0 products will include home gateways (as standalone devices or possibly built into DSL and cable modems), PC Cards and USB adapters, Haase said. Sometime this calendar year, he added, Siemens will add HomeRF 2.0 to Gigaset cordless phones.

Other HomeRF features include:

  1. Wireless connections up to 150 feet in typical homes, despite severe interfere, as with the previous spec. The data rate falls back in increments depending on distance and the materials used in the walls.

  2. Interference avoidance from microwave ovens, cordless phones and other household products.

The previous HomeRF version supports wireless PC networking and cordless voice telephony at an effective throughput of 500Kbps-600Kbps — enough to simultaneously surf the Internet through a broadband connection, print files and play MP3 files residing on a second PC's hard drive. The previous version could also support up to three simultaneous streams of 128Kbps MP3 audio.

The 2.0 technology delivers enough bandwidth to distribute multiple streams of uncompressed CD audio (requiring anywhere from 1.2Mbps-1.5Mbps of throughput, various suppliers said), create high-quality wireless speaker systems, or increase the number of simultaneous cordless-voice conversations to eight. Wireless distribution of Dolby Digital 5.1-channel audio from DVD-Video players, satellite receivers, cable boxes and digital TV broadcasts is also possible with less likelihood of interruption caused by limited bandwidth.

The 1.6Mbps standard, Haase noted, will be used in an audio device expected to be available to consumers in the third quarter from an unnamed supplier who will OEM the product from Simple Devices. The product will be an "Internet receiver" that wirelessly streams songs from a PC's hard drive for playback through a home stereo system. Another Simple Devices product, available in the second quarter to consumers through an undisclosed OEM partner, will be a Palm sled that lets Palm users wirelessly browse the Web around the house.

HomePlug: In advancing its spec, the HomePlug alliance completed field tests of prototype equipment in about 500 U.S. and Canadian homes up to 7,000 square feet in size. Testing almost 10,000 different outlet-to-outlet wiring paths, the group concluded that the equipment met or exceeded the spec's minimum performance standards, which mandate 10Mbps Ethernet-class performance, said HomePlug president Alberto Mantovani, director of Conexant's personal computing division.

In the test, HomePlug used 14Mbps Intellon technology available in an Intellon chip that began shipping in quantity in May for use in products expected in the third quarter, Intellon said. The tests produced maximum throughputs up to 8.4Mbps, with 7.6Mbps achieved about half the time and 5Mbps achieved about 80 percent of the time, Mantovani said.

Final spec ratification is expected in late June or July, and Mantovani said products using the Intellon chip are expected to be fully compliant with the 1.0 spec.

Future versions of the spec will accelerate throughput, and Intellon has said it will deliver 100Mbps HomePlug chipsets in two years.

"The first HomePlug products will most likely be PC-networking products," said Mantovani, "but we expected members to deliver audio-related consumer electronics products this year. Broadband modems and gateways will quickly be adapted to include the technology, perhaps by year end."

Earlier this year, Phonex said it planned Ethernet-to-power line adapters at a targeted $90 to $100 each and due in July or August, with a USB version due 90 days later, and an adapter supporting both Ethernet and USB connections due sometime next year.

The spec also includes multimedia and voice-over-Internet QoS and ability to coexist with existing power line network technologies.

802.11b HR: The IEEE direct-sequence spread-spectrum technology, which operates at a data rate up to 11Mbps in the 2.4GHz band, retained its lead in product availability with the announcement that WECA certified another 21 products as interoperable, bringing the number to 112 from 43 companies.

The latest products include wireless access points from 3Com, Cisco and Xircom, a Compaq USB adapter, and PC Card and mini-PCI card from Dell. Certification entitles the products to bear the Wi-Fi logo.

The WECA alliance recently added another six members to bring its roster to 80 manufacturers.