AirPort
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| AirPort | |
|---|---|
 The AirPort logo as seen in the AirPort Utility icon. |
|
| Type: | Wireless Base Stations and Cards |
| Developer: | Apple Inc. |
| Released: | July 21, 1999 |
| Website: | Apple.com - AirPort Extreme |
AirPort is a local area wireless networking brand from Apple Inc. based on the IEEE 802.11b standard (also known as Wi-Fi) and certified as compatible with other 802.11b devices. A later family of products based on the IEEE 802.11g specification is known as AirPort Extreme. The latest family of products is based on the draft-IEEE 802.11n specification and carries the same name.
AirPort and AirPort Extreme in common usage can refer to the protocol (802.11b and 802.11g, respectively), the expansion card or the base station.
In Japan, the name "AirPort" had already been registered by I-O DATA (I-O DATA page in english translated by www.translate.google.com), causing Apple to sell it under the name "AirMac" there.
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[edit] Overview
AirPort debuted on July 21, 1999 at the Macworld Expo in New York City with Steve Jobs picking up an iBook supposedly to give the cameraman a better shot as he surfed the Web—the applause quickly built as people realized there were no wires. The initial offering included an optional expansion card for Apple's new line of iBook notebooks, plus an AirPort Base Station. The AirPort card (a repackaged Proxim—ORiNOCO Gold Card PC Card adapter) was later added as an option for almost all of Apple's product line, including PowerBooks, eMacs, iMacs, and Power Macs. Only Xserves do not have it as a standard or optional feature. The original AirPort system allowed transfer rates up to 11 Mbit/s and was commonly used to share Internet access and files between multiple computers.
On January 7, 2003, Apple introduced AirPort Extreme, based on the 802.11g specification. AirPort Extreme allows theoretical peak data transfer rates of up to 54 Mbit/s, and is fully backward-compatible with existing 802.11b wireless network cards and base stations. Several of Apple's current desktop computers and portable computers, including the MacBook Pro, MacBook, Mac mini, and iMac ship with an AirPort Extreme card as standard (as of May 2006). All other modern Macs have an expansion slot for the card. AirPort and AirPort Extreme cards are not physically compatible: AirPort Extreme cards cannot be installed in older Macs, and AirPort cards cannot be installed in newer Macs. The original AirPort card was discontinued in June 2004.
On June 7, 2004, Apple released the AirPort Express Base Station as a lower-priced, more mass-market alternative to the AirPort Extreme Base Station.
On January 9, 2007, Apple unveiled a new AirPort Extreme Base Station, now with styling similar to that of the Mac mini and Apple TV.[1]
Although AirPort and AirPort Extreme cards are available only for Macintosh computers, all AirPort base stations and cards work with third-party base stations and wireless cards that conform to the 802.11a, 802.11b or 802.11g networking standards. It is not uncommon to see wireless networks composed of several types of AirPort base station serving old and new Macintosh, Microsoft Windows, and even Linux systems. Apple's software drivers for AirPort Extreme also support some Broadcom and Atheros-based PCI Wireless adapters when fitted to Power Mac computers. Due to the nature of draft-n hardware, there is no assurance that the new model will work with 802.11n routers and access devices from other manufacturers.
[edit] Base stations
An AirPort base station is used to connect AirPort-enabled computers to the Internet, each other, a wired LAN, and/or other devices.
[edit] AirPort
The original base station (known as Graphite) featured a modem and an Ethernet port. It was based on the same Lucent WaveLAN Bronze PC Card as the AirPort Card, and used an embedded 486 processor. It was released July 21, 1999. The Graphite AirPort Base Station is functionally identical to the Lucent RG-1000 wireless base station.
A second generation model (known as Dual Ethernet or Snow) was introduced on November 13, 2001. It added a second Ethernet port, allowing it to share a wired network connection with both wired and wireless clients. Also new was the ability to connect to America Online's dial-up service—a feature unique to Apple base stations. This model was based on Motorola's PowerPC 860 processor.
[edit] AirPort Extreme (802.11g)
The AirPort Base Station was discontinued after the updated AirPort Extreme was announced on January 7, 2003. In addition to providing wireless connection speeds of up to a maximum of 54 Mbit/s, it adds an external antenna port and a USB port. The antenna port allows the addition of a signal-boosting antenna, and the USB port allows the sharing of a USB printer. A connected printer is made available via Bonjour's "zero configuration" technology and IPP to all wired and wireless clients on the network. A second model (M8930LL/A) lacking the modem and external antenna port was briefly made available, but then discontinued after the launch of AirPort Express (see below). On April 19, 2004, a third version, marketed as the AirPort Extreme Base Station (with Power over Ethernet and UL 2043), was introduced that supports Power over Ethernet and complies to the UL 2043 specifications for safe usage in air handling spaces, such as above suspended ceilings. All three models support the Wireless Distribution System (WDS) standard. The model introduced in January 2007 does not have a corresponding PoE, UL-compliant variant.
An AirPort Extreme base station can serve up to 50 wireless clients at once, and thus is more suitable for a corporate environment than the AirPort Express.
[edit] AirPort Express (802.11g or 802.11n)
The AirPort Express (M9470LL/A) is a simplified and compact AirPort Extreme base station. It allows only up to 10 networked users, and includes a new feature called AirTunes. It did not replace the AirPort Extreme base station. It was introduced by Apple on June 7, 2004 and includes an analog/optical audio mini-jack output, a USB port for remote printing, and a single Ethernet port.
The main processor in the AirPort Express (802.11g version) is a Broadcom BCM4712KFB wireless networking chipset. This has a 200 MHz MIPS processor built in. The audio is handled by a Texas Instruments Burr-Brown PCM2705 16-bit digital-to-analog converter.
The device can be used as an Ethernet-to-wireless bridge under certain wireless configurations.
An updated version (MB321LL/A) featuring the faster 802.11n draft specification and operation in both the 2.4GHz and 5GHz bands was released on March 17, 2008 with almost all other features identical. The revised unit includes an 802.11n Only(5 GHz) mode, which allows adding Draft N to an existing 802.11b/g network without disrupting existing connections, while preserving the increased throughput that Draft N can provide[2]. Up to 10 wireless units can connect to this AirPort Express.
This newer version also allows you to extend the range of your network, rather than simply joining it.
[edit] AirTunes
AirTunes allows an AirPort-enabled computer with the iTunes music player to send a stream of music to multiple (three to six, in typical conditions) stereos connected to an AirPort Express.
The AirPort Express' streaming media capabilities use Apple's Remote Audio Output Protocol (RAOP), a proprietary variant of RTSP/RTP. Using WDS-bridging,[3] the AirPort Express can allow AirTunes functionality (as well as Internet access, file and printer sharing, etc.) across a larger distance and multiple wired and wireless clients.
AirTunes can be controlled by a Keyspan USB-enabled infrared remote control plugged into the USB port, but the Apple Remote's volume buttons cannot control AirTunes. AirTunes will not stream a video's audio.
Several third-party AirPort Express clients can connect an AirPort Express to sources other than iTunes, including Airfoil for Mac OS X and Windows, JustePort for Windows, and raop-play for Linux as well.
[edit] AirPort Extreme (802.11n)
The AirPort Extreme was updated on January 9, 2007, to support the 802.11a/b/g and draft-n protocols. This revision also adds two LAN ports for a total of three.[4] It now more closely resembles the 6.5-inch-square-shaped Apple TV and Mac mini, and is about half the height of the mini.
The new AirPort Disk feature allows users to plug a USB hard drive into the AirPort Extreme for use as a Mac OS X or Windows file server.[5] Users may also connect a USB hub and printer.
The AirPort Extreme has no port for an external antenna.
On August 7, 2007, the AirPort Extreme began shipping with Gigabit Ethernet, matching most other Apple products.
On March 19, 2008, Apple released a firmware update for both models of the AirPort Extreme to allow AirPort Disks to be used in conjunction with Time Machine, similar to the functionality provided by Time Capsule.[6] This feature may work, but is not officially supported by Apple.
[edit] AirPort Cards
An AirPort Card is an Apple-branded wireless card used to connect to wireless networks such as those provided by an AirPort Base Station.
[edit] AirPort 802.11b Card
The original model, known as simply AirPort Card, was a re-branded Lucent WaveLAN Gold PC card, in a modified housing that lacked the integrated antenna. It was designed to be capable of being user-installable. It was also modified in such a way that it could not be used in a regular PCMCIA slot (At the time it was significantly cheaper than the official WaveLAN Gold card). An AirPort card adapter is required to use this card in the slot loading iMacs.
[edit] AirPort Extreme 802.11g cards
Corresponding with the release of the AirPort Extreme Base Station, the AirPort Extreme Card became available as an option on the current models. It is based on a Broadcom 802.11g chipset and is housed in a custom enclosure that is mechanically proprietary, but is electrically compatible with the Mini PCI standard. It was also capable of being user-installed.
Variants of the user installable AirPort Extreme Card are marked A-1010 (early North American spec), A-1026 (current North American spec), A-1027 (Europe/Asia spec (additional channels)) and A-1095 (unknown).
A different 802.11g card was included in the last iteration of the PowerPC-based PowerBooks and iBooks. A major distinction for this card was that it was the first "combo" card that included both 802.11g as well as Bluetooth. It was also the first card that was not user-installable. It was again a custom form factor, but was still electrically a Mini PCI interface for the Broadcom WLAN chip. A separate USB connection was used for the on-board Bluetooth chip.
[edit] Integrated AirPort Extreme 802.11a/b/g and /n cards
As AirPort Extreme began to come standard on all notebook models, Apple phased out the user-installable designs in their notebooks, iMacs and Mac minis by mid 2005, moving to an integrated design. AirPort continued to be an option, either installed at purchase or later, on the Power Mac G5 and the Mac Pro.
With the introduction of the Intel-based MacBook Pro in January 2006, Apple began to use a standard PCI Express mini card. Cards with this form factor are now used in all AirPort-equipped Macintoshes.
In early 2007, Apple announced that most Intel Core 2 Duo-based Macs, which had been shipping since October 2006, already included AirPort Extreme cards compatible with the draft-802.11n specification. 802.11n capability was unlocked by an enabler included with the new draft-802.11n-capable AirPort Extreme Base Station, or by purchasing the enabler separately from the Apple Store online.[7] This card was also a PCI Express mini design, but used three antenna connectors in the notebooks and iMacs, in order to use a 2x3 MIMO antenna configuration. The cards in the Mac Pro and Apple TV have 2 antenna connectors and support a 2x2 configuration. To see which protocols your AirPort card supports, use the Network Utility application located in (Applications -> Utilities) and look at the model. Click here for a screenshot [8].
[edit] Security
AirPort and AirPort Extreme support a variety of security technologies to prevent eavesdropping and unauthorized network access, including several forms of cryptography.
The original graphite AirPort base station used 40-bit Wired Equivalent Privacy (WEP). The second generation model (known as Dual Ethernet or Snow) AirPort base station, like most other Wi-Fi products, used 40-bit or 128-bit Wired Equivalent Privacy (WEP). AirPort Extreme and Express base stations retain this option, but also allow and encourage the use of Wi-Fi Protected Access (WPA) and, as of July 14, 2005, WPA2.
AirPort Extreme cards, using the Broadcom chipset, have the Media Access Control layer in software. The driver is closed source.
[edit] See also
[edit] Notes
- ^ Apple Introduces New AirPort Extreme with 802.11n, Apple.com, retrieved 1/9/07.
- ^ Designing Airport Networks (PDF). Apple, Inc. (2008-03-17). Retrieved on 2008-03-26., p.21
- ^ Apple WDS Setup
- ^ Apple.com - AirPort Extreme
- ^ Apple.com - AirPort Extreme - Sharing, Retrieved on 1/17/07. [Dead Link]
- ^ Time Machine now works with AirPort Extreme's AirDisk feature. Engadget.com (2008-03-19). Retrieved on 2008-03-19.
- ^ Apple Introduces New AirPort Extreme with 802.11n, Apple.com. 2007-01-09. Retrieved on 2007-04-07.
- ^ AirPort Extreme 802.11n* Enabler @ Apple store
[edit] External links
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