Overheard in the tech blogosphere » Wireless

Overheard – Wireless Distribution System

Margaret Rouse — Tue, 02 Feb 2010 16:53:12 +0000

WDS uses standard 802.11 wireless to forward traffic between access points, as an alternative to Ethernet or another wired distribution network. In effect, WDS turns a pair of APs into a pair of wireless bridges or repeaters…WDS is based on the 802.11 standard, but is not fully specified by that standard, so WDS links often work only between same-vendor APs (or APs using the same chipset).

Lisa Phifer, What’s the expected range on a pair of Belkin 54G routers in wireless bridge mode?

Today’s WhatIs.com Word of the Day is Wireless Distribution System.

Overheard – Single stream 802.11n for the iPhone?

Margaret Rouse — Mon, 06 Apr 2009 17:37:06 +0000

802.11n was developed as a range and speed booster, employing multiple antennas and two or more radios to work over greater distances (sending a stronger signal, having better receiver sensitivity) and at greater speeds (improved encoding, multiple spatial paths, double-wide channels). That’s fine for laptops, desktops, and routers, but it’s hard to cram that much radio technology into a battery-powered mobile device without making the time between charges unusably brief.

Glenn Fleishman, Does the iPhone Need 802.11n?

That’s where single-stream 802.11n comes in. With single-stream 802.11n, only a single radio and single antenna are used…

…802.11n’s single stream encoding is 65 Mbps, where 30 to 50 Mbps of throughput is possible. So you lose wide channels, antenna diversity, and multiple streams, but could gain 50 percent or more in net throughput.

Overheard – 2009, the year of the netbook

Margaret Rouse — Thu, 08 Jan 2009 15:44:43 +0000

Just as General Motors must wean itself off lumbering SUVs, so may Intel, Hewlett-Packard, Sony, Toshiba, et al., be forced, to some extent, to wean themselves off high-profit notebook computers.

Brooke Crothers, Intel warning casts cloud over CES

Netbook is the big buzzword this year at CES. I remember having what vendors are now calling a netbook about ten years ago. I couldn’t load any software on it, but I could access email and the Internet. At this very moment, I can’t remember what it was called — but I remember getting it at Circuit City and using it in the classroom with WinGate as my proxy server. (For several years, WinGate was the bane of my existence.)

On a totally unrelated note, Jeopardy is celebrating its 25th anniversary with host Alex Trebeck by filming 11 episodes at CES. You have to love a show that gives quizzes and penalizes contestants for not using the words “what is….”

Overheard: What’s another name for white space device? Brick

Margaret Rouse — Mon, 24 Nov 2008 15:33:33 +0000

Unfortunately for the companies developing these devices, they’ve yet to demonstrate a device that accurately and consistently senses broadcast and wireless microphone signals. The development of these devices is absolutely crucial to the white space debate. If they can’t sense signals, they are essentially useless bricks.

Shelly Palmer, White Space – A Big White Lie

Thanks to Alex Howard for finding today’s “Overheard” quote!

Overheard: Cognitive radio will change wireless fee structures

Margaret Rouse — Tue, 11 Nov 2008 02:51:07 +0000

The potential for cognitive radio technology to redefine existing wireless services becomes clear when one considers their economics. A monthly cell-phone service bill, for instance, contains charges for leasing radio spectrum, renting cell towers and purchasing the handset, as well as the amortization of the hardware at the cell base site, the cost of interconnections among cell sites, billing expenses and network operator profit. These fees pay for the investments that cellular service providers make to create and operate dedicated RF networks.

Steven Ashley, Cognitive Radio

Overheard: White space, the Dixie Chicks and wireless microphones

Margaret Rouse — Mon, 03 Nov 2008 20:59:31 +0000

As part of an ongoing effort to bar internet devices from the country’s television white spaces, Goosoft-battling government lobbyists have rolled out two pillars of the American heartland: God and Dolly Parton.

Cade Metz, Anti-white-space lobby enlists God, Dolly Parton

What do Dolly Parton, Neil Diamond, the Dixie Chicks, Clay Aiken, Pastor Joel Osteen and Guns N’ Roses have in common? They all use wireless microphones and they’ve all joined together to ask the FCC to delay a vote on a proposal that would open up unused white space in the wireless spectrum.

The white spaces are empty “buffer” channels scattered throughout the 54- to 698-MHz region of the RF spectrum that were set up when TV was in its infancy to prevent interference. Now that we’re all moving to digital TV and analog is dead, the white space below 700 MHz could be up for grabs. Because the space is currently being used for wireless microphone transmission, the League of American Theatres & Producers and others don’t want the FCC to make the space freely available. They want to keep the status quo because they’re worried about interference issues — despite a lot of testing on the FCC’s part that says it shouldn’t be a problem.

Google seems to be leading the charge to make the unused white space available for a new generation of wireless devices, pretty much saying that current wireless microphones have to use FDMA technology, but if the white space spectrum was opened up, wireless mic vendors could make new microphones that use CDMA-based technologies and that would take care of the problem — as long as nobody minds going out and getting new sound systems.

The FCC will have the final word. As of today, you need a license to operate a wireless mic unless it operates in the 49 MHz, AM/FM | broadcast, 902-928 MHz or 2.4 GHz band.

UPDATE: The FCC voted unanimously yesterday (Election Day) to allow conditional unlicensed use of the “white space” television spectrum.

The FCC says that to prevent white space devices from interfering with each other, the devices should use spectrum sensing (scan for unused channels) and geo-location (a technology that cross-references your location with a database of licensed spectrum users in your area.)

What does this decision mean for those of us who don’t use wireless microphones?

Well, the waves in white space can travel through walls. What it means for us is that someday soon you’ll be able to get broadband Internet in every part of the county and when our kids are talking to our grandchildren, they’ll say things like “When I was your age, people had to go outside to the driveway to talk on their cell phone.” I can’t wait.

Overheard: Municipal wireless and privacy

Margaret Rouse — Tue, 22 Jul 2008 16:22:07 +0000

While some cities have seen their dreams of providing wireless Internet access for all fade, others have forged ahead with wireless networks for an altogether different purpose: surveillance.

Joshua Brockman, Cities Gone Wireless: Safety Or Surveillance?

Today, public safety is the “largest and most successful sector” in the municipal wireless market, according to MuniWireless.com, a Web site devoted to tracking wireless broadband projects and technologies.

Overheard: WiMAX gets a marketing makeover

Margaret Rouse — Mon, 19 May 2008 12:46:07 +0000

It turns out the announcement isn’t a new vaporware wireless technology, it’s my favorite old vaporware wireless technology, WiMax. Sprint finally figured out what to do with it.

The unbelievably frustrating part is that Sprint has pretty much slipped the deployment plan for WiMax by another two years. It’s hard to get excited about a new technology, no matter how great the investors, when I have zero confidence in the companies’ ability to deliver.

Michael Mace, WiMax gets closer and further away at the same time

The involvement of Google means we’re very likely to get a pretty much open ecosystem on a major wireless network, which Silicon Valley has been collectively screaming about for years. The size of the investments mean there is a lot of money available to build out the network. People ought to be dancing in the streets here, but instead most of them appear to be either yawning or throwing spitwads.

I’d be out there dancing myself if it weren’t for the slip in the schedule.

Hat’s off to Michael Mace for explaining the real buzz around WiMAX.

Overheard: WildCharge is the real deal

Margaret Rouse — Thu, 27 Mar 2008 12:44:01 +0000

I set my WildCharge pad up on my nightstand. After a phone chat, I tossed my RAZR cellphone over to the charging pad; four magnetic contact points on the phone’s adapter helped it stick to the pad. A chime indicated my phone made electrical contact and started charging…I really grew fond of not hunting for the correct cord to charge my phone. Instead, I’d finish conversations, reach over and simply drop my phone down as if I was laying it on the table.

Katherine Boehret, A Pad to Easily Power Up Your Phone

I really want one of these.

Overheard: Forget hiding your SSID — pay attention to what you name it

Margaret Rouse — Tue, 25 Mar 2008 13:53:48 +0000

Many people (including myself) have tried to “hide” SSID as a security measure. Unfortunately, efforts to hide SSID ultimately fail and degrade overall WLAN performance.

Lisa Phifer, Configuring service set identifiers

SSIDs are analogous to Windows workgroup names. PCs use those names to browse a network neighborhood and discover others in the same workgroup. When a PC actually tries to access a fileshare, permission is determined by computer name, user name and password. Similarly, stations use SSID to discover APs in the same ESS, but access depends upon other parameters like the station’s address, WEP keys and 802.1X credentials. Access requests must carry the right name, but the workgroup or ESS name is not a password – it identifies the resource to be accessed.