Mon, 5 February 2007
The IEEE 802.11 Working Group on January 19 unanimously approved a new Draft 2.0 802.11n proposed standard. In this podcast we take a look at this new draft standard and also look at earlier standards including 802.11 a, b and g.
Question: Mike – before we get into the technology….. this new draft standard was approved unanimously by a 100 yes, 0 no, 5 abstaining vote, but it is still not a standard yet. What is the rest of the process to get this to be a standard?
The IEEE 802 Plenary committee meeting will be held March 19th in Orlando, Florida and between now and then the IEEE will collect votes and comments with two questions asked.
The first question that will be asked by letter ballot over a 15 day period is "Should 802.11n Draft 1.10 be forwarded to Working Group letter ballot as Draft 2.0?" If this question passes by 75% or more then a second question will be asked by letter ballot "Should 802.11n Draft 2.0 be forwarded to Sponsor Ballot?"
If both of these pass by 75% or more then on the IEEE will start moving the Draft 2.0 towards a standard. It looks like they will move this standard along much more rapidly with approval before the final approval date of October 2008 on the current IEEE timeline found on their website.
Since late 1990s, IEEE has approved four standards for wireless LANs:
• IEEE 802.11
• IEEE 802.11b
• IEEE 802.11a
• IEEE 802.11g
IEEE 802.11n expected to be approved by 2008
Specified that wireless transmission could take place via infrared (IR) or radio signals
• Infrared Transmissions:
– Can send data by the intensity of the infrared light wave
– Light spectrum: All types of light
– Infrared light: Can be used for wireless transmissions
– Emitter: Device that transmits a signal
– Detector: Device that receives a signal
• Does not interfere with other communications signals
• Not affected by other signals
• Does not penetrate walls
• Lack of mobility
• Limited range
• Confined to indoor use
• Slow transmission speed
• Radio Wave Transmissions:
– Radio waves can penetrate through objects
• Provides mobility
– Radio waves travel longer distances
– Can be used indoors and outdoors
– Radio waves can travel at much higher speeds than infrared transmissions
– IEEE 802.11 standard outlining radio wave transmissions has become preferred method for wireless LANs
Question: Can you tell us about the different standards over time? Can you start out with 802.11a?
Release Date Op. Frequency Data Rate (Typ) Data Rate (Max) Range (Indoor) October 1999 5 GHz 25 Mbit/s 54 Mbit/s ~30 meters
• IEEE 802.11a standard specifies maximum rated speed of 54 Mbps
– Also supports 48, 36, 24, 18, 12, 9,and 6 Mbps transmissions using U-NII band
• 802.11a and 802.11b published at same time
– 802.11a came to market later due to technical issues and high production cost
• Range of 802.11a is less than that of 802.11b
How about 802.11b?
Release Date Op. Frequency Data Rate (Typ) Data Rate (Max) Range (Indoor) October 1999 2.4 GHz 6.5 Mbit/s 11 Mbit/s ~30 meters (~98 ft)
• 802.11 standard’s 2 Mbps bandwidth not sufficient for most network applications
• 802.11b amendment added two higher speeds (5.5 Mbps and 11 Mbps) to original 802.11 standard
– Uses ISM band
• Supports wireless devices up to 115 meters (375 feet) apart
– Radio waves decrease in power over distance
– 802.11b standard specifies that, when devices out of range to transmit at 11 Mbps, devices drop transmission speed to 5.5 Mbps
Release Date Op. Frequency Data Rate (Typ) Data Rate (Max) Range (Indoor) June 2003 2.4 GHz 24 Mbit/s 54 Mbit/s ~30 meters (~98 ft)
• Effort to combine best features of 802.11a and 802.11b
– Data transfer rates to 54 Mbps
– Support devices up to 115 meters apart
• 802.11g standard specifies that devices operate entirely in ISM frequency
Now, how about some detail on n?
Release Date Op. Frequency Data Rate (Typ) Data Rate (Max) Range (Indoor) January 2007 2.4 GHz or 5 GHz 200 Mbit/s 540 Mbit/s ~50 meters (~165 ft)
Projected IEEE 802.11n
• Currently in evaluation stage
• Top speed of 802.11n standard will be anywhere from 100 Mbps to 500 Mbps
• Ratification may not occur until 2008
– Devices based on standard may appear prior to that
• 802.11 pre-N
According to TG Daily and posted at Netstumbler.com Intel will announce the release of a new 802.11n WiFi chipset code-named Kedron on today, 1/30/07. According to Netstumbler.com:
The firm originally planned to launch the product along with its new mobile chipset code-named Santa Rosa in the second quarter of 2008. The Kedron 802.11 n draft-capable version will be named "WiFi Link 4965 AGN" while the non-draft n capable variant will go by the name "WiFi Link 4965 AG".
802.11, with its high theoretical data rates of up to 540 Mbit/s, has been bouncing around without a standard since first proposed by the IEEE in 2004. The lack of a standard has not stopped the manufacturers with the first pre-standard or “pre-n? routers made available to consumers in April 2006. I am sure you have seen these products from most of the big manufacturers including D-link, Netgear and Buffalo for sale in the Sunday papers and many of you may have actually purchased pre-n devices.
It looks like we may be getting a little closer to a standard now. On January 19 the IEEE 802.11 Working Group unanimously approved a request by the 802.11n Task Group to issue a new Draft 2.0 of the proposed standard.
With the Apple TV product announcement at Mac World it may be more than just a coincidence that we are seeing movement now. According to Netstumbler.com, AppleInsider and MacFixIt are reporting Apple will charge $1.99 per machine to enable the draft 802.11 standard on:
…. any Mac running Core 2 Duo or Xeon processors, with the exception of the entry-level 17-inch 1.83GHz iMac. These machines have had 802.11n technology built in, but not switched on.
If you do go out and purchase a new $179 Apple AirPort Extreme Base Station, you will not have to pay the $1.99 per Apple machine for the upgrade. It is important for Apple to move quickly here because the Apple TV product shipping in February depends on the higher 802.11 bandwidth for video and audio streaming. The Apple TV box connects to your ED or HD television and content is streamed from a Mac or PC running iTunes. You can get more information on the Apple TV box here: http://store.apple.com
It is important to realize these are local area network bandwidths – this means transfers machine to machine inside your home or business network will be very fast but you will still be limited by your broadband provider bandwidth when accessing the Internet.
Intel To Launch 802.11n Wi-Fi Chipset Next Week: http://www.netstumbler.com/2007/01/25/report-apple-will-charge-for-802.11n-access/
802.11n Devices Are Fully Compatible With .11b/g: http://www.netstumbler.com/2007/01/25/report-apple-will-charge-for-802.11n-access/
Report: Apple Will Charge For 802.11n Access: http://www.netstumbler.com/2007/01/25/report-apple-will-charge-for-802.11n-access/