The AirPort Extreme is a residential gateway product from Apple Inc. combining the functionality of a Router, Network switch, Wi-Fi base station and NAS as well as varied other functions. The name AirPort Extreme also refers to Apple's implementation of the (802.11g) protocol and the expansion cards and base stations that employ it. On January 9, 2007, the AirPort Extreme Base Station was updated to support the 802.11a/b/g and Draft-N protocols. This version was renamed to just AirPort Extreme. This revision also adds two LAN ports for a total of three, and removes the built-in modem, external antenna port, and added support for Power over Ethernet which has since been removed. It now more closely resembles the square-shaped 1st generation Apple TV and Mac mini, and is about the same size as the Mini. The AirPort Extreme base station can serve a maximum of 50 wireless clients simultaneously.
- Fully featured 802.11n Wi-Fi base station
- Sleep Proxy Service
- 4 Ethernet ports (3 LAN ports, 1 WAN port) – all ports are gigabit Ethernet on newer versions
- USB interface for disk and printer sharing
- Built-in file server (AFP and SMB)
- Runs VxWorks Operating System by WindRiver
AirPort Disk 
The new AirPort Disk feature allows users to plug a USB hard drive into the AirPort Extreme for use as a network-attached storage (NAS) device for Mac OS X and Microsoft Windows clients. Users may also connect a USB hub and printer. The performance of USB hard drives attached to an AirPort Extreme is slower than if the drive were connected directly to a computer. This is due to the processor speed on the AirPort extreme. Depending on the setup and types of reads and writes, performance ranges from 0.5 to 17.5 MB/s for writing and 1.9 to 25.6 MB/s for reading. Performance for the same disk connected directly to a computer would be 6.6 to 31.6 MB/s for writing and 7.1 to 37.2 MB/s for reading. NTFS formatted drives are not supported.
Apple AirPort Extreme Models by Generation 
Round generation 
The round models were later replaced with updated with square shaped cases.
First generation 
On January 9, 2007 the AirPort Extreme began shipping.
Second generation 
On March 19, 2008, Apple released a firmware update for both models of the AirPort Extreme that according to third party reports
allows AirPort Disks to be used in conjunction with Time Machine, similar to the functionality provided by Time Capsule.
Third generation 
On March 3, 2009, Apple unveiled a new AirPort Extreme with simultaneous dual-band 802.11 Draft-N radios. This allows full 802.11 Draft-N 2x2 communication in both 802.11 Draft-N bands at the same time.
Fourth generation 
On October 20, 2009, Apple unveiled an updated AirPort Extreme base station with antenna improvements.
Fifth generation 
On June 21, 2011, Apple unveiled an updated AirPort Extreme base station, referred to as AirPort Extreme 802.11n (5th Generation).
Frequency range (MHz) Mode AirPort Extreme model Output power (dBm) Output power (mW) Comparison (percents) Difference (percents) 2412–2462 802.11b Previous 24.57 286.42 100 -10.3 Current 24.10 257.04 89.7 802.11g Previous 21.56 143.22 100 +114.8 Current 24.88 307.61 214.8 802.11n HT20 Previous 21.17 130.92 100 +96.8 Current 24.11 257.63 196.8 5745–5825 802.11a Previous 23.07 202.77 100 +61.1 Current 25.14 326.59 161.1 5745–5805 802.11n HT20 Previous 22.17 164.82 100 +104.6 Current 25.28 337.29 204.6 5755–5795 802.11n HT40 Previous 21.44 139.32 100 +181.8 Current 25.94 392.64 281.8
Comparison Chart 
Approx. release date Consumer Nickname AirPort Extreme Model Wireless standard Gigabit ethernet Guest network Radio Type MIMO config IPv6 router mode** Jan 7, 2003 round/original M8799LL/A A1034 802.11b/g No No Single band
?? No Jan 9, 2007 generation 1 MA073LL/A A1143 802.11a/b/g/n* No No Dual band
2.4 GHz OR 5 GHz
3x3:2 No Aug 7, 2007 generation 2 MB053LL/A A1143 802.11a/b/g/n* Yes No Dual band
2.4 GHz OR 5 GHz
3x3:2 No Mar 3, 2009 generation 3 MB763LL/A A1301 802.11a/b/g/n* Yes Yes Dual band (simultaneous)
2.4 GHz AND 5 GHz
2x2:2 (in each band) No Oct 20, 2009 generation 4 MC340LL/A A1354 802.11a/b/g/n Yes Yes Dual band (simultaneous)
2.4 GHz AND 5 GHz
3x3:3 (in each band) Yes (does not work over PPPoE). Jun 21, 2011 generation 5 MD031LL/A A1408 802.11a/b/g/n Yes Yes Dual band (simultaneous)
2.4 GHz AND 5 GHz
3x3:3 (in each band) Yes (does not work over PPPoE).
*802.11n draft-specification support in Generation 1, 2, and 3 models.
**All models support IPv6 tunnel mode.
See also 
- Power over Ethernet kit for Airport Extreme Base Station - TUAW
- "Mac OS X v10.6: About Wake on Demand (Apple Article HT3774)" (in several languages). Apple. August 27, 2009. Retrieved September 15, 2009. "Setting up Wake on Demand", "Setting up a Bonjour Sleep Proxy"
- Apple.com – AirPort Extreme – Sharing, Retrieved on January 17, 2007.
- "Airport Extreme (5th Gen) and Time Capsule (4th Gen) Review – Faster WiFi". Airport Extreme (5th Gen) and Time Capsule (4th Gen) Review. AnandTech. Retrieved October 24, 2011.
- "Time Machine now works with AirPort Extreme's AirDisk feature". Engadget.com. March 19, 2008. Archived from the original on March 20, 2008. Retrieved March 19, 2008.
- "OS X Mountain Lion: Disks you can use with Time Machine". Apple. July 31, 2012. Retrieved October 9,2012.
- "Time Machine doesn't back up to AirPort Extreme AirPort Disks". Apple. April 25, 2012. Retrieved October 9, 2012.
- Test Report – Previous version Federal Communications Commission (FCC)
- Test Report – Current version Federal Communications Commission (FCC)
- About the Guest network feature of AirPort Extreme and Time Capsule