Wireless IP video will take time

Wireless video could be used for mobile videoconferencing and to remotely monitor surveillance equipment.

By Jason Meserve
Network World, 11/06/00

Science fiction movies are full of scenes with characters looking at crystal-clear interactive video on a laptop screen or even a cell phone while driving an automobile. While these scenes may be a common occurrence on the big screen, it's a near impossibility today.

When and if it becomes a reality, wireless video could be used for such applications as mobile videoconferencing, training videos for technicians and salespeople in the field, and remote monitoring of cameras and surveillance equipment.

Wireless video seems to be following the same path as desktop videoconferencing: a lot of hype and expectations, but very little real-world success. Most broadband wire-line networks barely deliver TV-quality video to the desktop in a small window, never mind full screen. It's nearly impossible to get mediocre quality video on a tiny black-and-white cell phone or Palm-like device with a fraction of the computing power of today's big desktop PCs.

"The Palm is a reference point for power consumption, display and processor: It's got nominal memory and imaging, and a terrible network connectivity," says Edward Bronson, president and founder of SolidStreaming, a software company in New York that is working on delivering streaming media to handheld devices. "If God wanted to screw up multimedia, the Palm has the right variables."

What's needed to make wireless video fly?

More powerful handheld devices with more functional operating systems
More high-speed, big-bandwidth delivery services
Better quality of service of existing and future networks.
More advanced technology cell phones.

Palms and similar devices typically have a black-and-white screen - though some units now ship with color displays - that measure 160 pixels by 160 pixels, a low-power 33-MHz processor, up to 8M bytes of RAM and a limited operating system in PalmOS. A cousin device running Microsoft's Windows CE operating system tends to be slightly more powerful, but not enough to support even VHS-quality video. Even lower on the totem pole of power is the cellular phone. Today's most advanced digital phones with Web browsing capability have nearly no memory and imited processing power.

Even if a device is physically capable of displaying high-quality multimedia, getting it there is a completely different problem. Currently, the best connection that can be made is 128K bit/sec on the Metricom Ricochet II wireless modem network, available in nine U.S. cities. But these modems are typically attached to a laptop, not a handheld device.

On the small devices, the average bandwidth available is 9.6K bit/sec to 14.4K bit/sec, with some carriers running 19.2K bit/sec. For video, this measly bandwidth is the equivalent of sucking a grapefruit through a coffee-stir straw. To put it in perspective, good-quality video on a PC requires about 300K bit/sec of continuous bandwidth.

"[Speeds of] 9.6K bit/sec and 19.2K bit/sec are just not fast enough for video," says Becky Diercks, director of wireless research at Cahners In-Stat Group of Scottsdale, Ariz. "Sprint Wireless has a special [service] for business people that goes up to 56K bit/sec, and more carriers will have that next year. But it's still not enough for full-motion video."

Increasing bandwidth is not as easy as opening new spectrum. Many say today's phones could not handle higher bandwidths without dissipating a lot of heat - which could literally burn the user.

In addition, quality of service (QoS) will become a factor. "Quality-of-service provisions need to be built in to the network," says Professor Aura Ganz of the University of Massachusetts at Amherst's Multimedia Network Lab. "The best-effort method used for voice is just not going to cut it with data."

Ganz and her colleagues are working on software for adding QoS to wireless networks. She's testing on a wireless LAN, but says the 70K-byte client application can be adapted easily to just about any type of device.

Despite numerous hurdles, companies such as PacketVideo, SolidStreaming, GEO Interactive and ActiveSky are dedicated to delivering multimedia to handheld devices. Most of the technologies being developed by these companies are still in the early stages.

GEO Interactive takes a hardware approach, putting its Emblaze decoder technology on a chip that is embedded into a cellular phone, which bypasses the phone's weak operating system and processing power, says Sasson Darwish, president of the New York company. The company also markets its own server technology designed to encode video for delivery to Emblaze-capable devices.

"In a wireless network, there is sometimes 30% to 50% packet loss, which voice can recover from because it is not using the whole bandwidth," Darwish says. "But video uses the whole bandwidth, so 30% to 50% is a problem - you need to recover on the device itself on the fly. You can't stop and rebuffer the packets."

Darwish claims the Emblaze technology is designed to alleviate the dropped-packets problem and deliver decent-quality video at 3 to 4 frame/sec. Samsung has licensed the chip design and is planning to implement it in cellular phones due out later this year.

PacketVideo and SolidStreaming use software to encode and decode video. PacketVideo encodes video into MPEG4 and streams out to client software installed on Windows CE devices. Plans for a Palm decoder are in the works as the platform becomes more robust, says Jim Carol, PacketVideo's CEO.

Like PacketVideo, SolidStreaming's contribution uses software on the server and client for the encoding/decoding process. The client is said to be about 3K bytes in size and does not require buffering to play a stream.

From the download and play side, FirePad and ActiveSky have or are developing clients for handheld devices that play locally stored content. The ActiveSky viewer is currently being used on the AtomFilms short film Web site for those who want to download clips to their Palms, says Azita Arvani, vice president of business development and strategy at ActiveSky in Redwood City, Calif.

Some applications vendors mentioned include streamed technical manuals that can be accessed from the field by technicians trying to solve a problem; small video mail clips; and training.

Attempting to tie these technologies together into some sort of standards framework is the Wireless Multimedia Forum. Hosted by Stardust Forums, the group of roughly 40 vendors is working to develop a framework for developing and delivering multimedia applications over a wireless network. The group, which works with the Wireless Application Protocol forum, Internet Engineering Task Force and other standards-setting organizations, is building an Application Requirements Document (ARD) and Recommended Technical Framework Document (RTFD).

The ARD outlines QoS, billing, hosting and other issues surrounding carriers and providers of wireless services. On the more technical front, the RTFD will deal with how applications such as uploading and downloading multimedia, video e-mail and videoconferencing should work. Martin Hall, chief technology officer of Stardust Forums, says RTFD 1.0 should be available by year-end.

What does all this mean for today's corporate user?

"We're not talking about watching 'The Matrix' on a handheld," SolidStreaming's Bronson says. "Short video clips, streaming radio, nanny and traffic cams are some of the substantive applications."

Until networks improve with the coming third- and fourth-generation wireless technology, corporate users can expect jerky video and some fluid animation on their devices.