2011/08/29

Airport extreme

AirPort

AirPort
Connectwaves 20070109.png
The AirPort logo as seen in the AirPort Utility icon.
Developer Apple Inc.
Type Wireless Base Stations and Cards
Release date July 21, 1999
Website http://www.apple.com/wifi

AirPort and AirPort Extreme are local area wireless networking products from Apple Inc. based on the IEEE 802.11 standard (also known as Wi-Fi).

AirPort and AirPort Extreme in common usage can refer to the protocol (802.11b, 802.11g and 802.11n, respectively), the expansion card or the base station.

In Japan, the line of products is marketed under the brand AirMac due to previous registration by I-O Data[1].

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 initial offering consisted of an optional expansion card for Apple's new line of iBook notebooks and an AirPort Base Station. The AirPort card (a repackaged Lucent 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 desktop computers and portable computers, including the MacBook Pro, MacBook, Mac mini, and iMac shipped with an AirPort Extreme (802.11g) card as standard. 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 "Swiss Army knife" product. It can be used as a portable travel router, using the same AC connectors as on Apple's AC adapters; as an audio streaming device, with both line-level and optical audio outputs; and as a USB printer sharing device, through its USB host port.

On January 9, 2007, Apple unveiled a new AirPort Extreme (802.11 Draft-N) Base Station, which introduced 802.11 Draft-N to the Apple AirPort product line. This implementation of 802.11 Draft-N can operate in both the 2.4 GHz and 5 GHz ISM bands, and has modes that make it compatible with 802.11b/g and 802.11a. The number of Ethernet ports was increased to four—one nominally for WAN, three for LAN, but all can be used in bridged mode. A USB port was included for printers and other USB devices. The Ethernet ports were later updated to Gigabit Ethernet on all ports. The styling is similar to that of the Mac mini and Apple TV.

On January 15, 2008, Apple introduced Time Capsule, an AirPort Extreme (802.11 Draft-N) with an internal hard drive. The device includes software to allow any computer running a reasonably recent version of Mac OS or Windows to access the disk as a shared volume. Macs running Mac OS X 10.5 and later, which includes the Time Machine feature, can use the Time Capsule as a wireless backup device, allowing automatic, untethered backups of the client computer. As an access point, the unit is otherwise equivalent to an AirPort Extreme (802.11 Draft-N), with four Gigabit Ethernet ports and a USB port for printer and disk sharing.

On March 17, 2008, Apple released an updated AirPort Express Base Station with 802.11 Draft-N 2x2 radio. All other features (analog and digital optical audio out, single Ethernet port, USB port for printer sharing) remained the same. At the time, it was the least expensive ($99) device to handle both frequency bands (2.4 GHz and 5 GHz) in 2x2 802.11 Draft-N.

On March 3, 2009, Apple unveiled AirPort Extreme and Time Capsule products 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.

On October 20, 2009, Apple unveiled the updated AirPort Extreme and Time Capsule products with antenna improvements (the 5.8 GHz model).

On June 21, 2011, Apple unveiled an updated AirPort Extreme base station, referred to as AirPort Extreme 802.11n (5th Generation).

All current AirPort base stations and cards work with third-party base stations and wireless cards that conform to the 802.11a, 802.11b, 802.11g, 802.11 Draft-N and 802.11 Final-N 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 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 802.11 Draft-N routers and access devices from other manufacturers.

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.

AirPort

The original AirPort (known as Graphite) features a modem and an Ethernet port. It employs a Lucent WaveLAN Silver PC Card as the Radio, and uses an embedded processor. It was released July 21, 1999. The Graphite AirPort Base Station is functionally identical to the Lucent RG-1000 wireless base station and can run the same firmware. Due to the original firmware-locked limitations of the Silver card, the unit can only accept 40-bit WEP encryption. Later aftermarket tweaks can enable 128-bit WEP on the Silver card. Aftermarket Linux firmware has been developed for these units to extend their useful service life.

A second generation model (known as Dual Ethernet or Snow) was introduced on November 13, 2001. It features a second Ethernet port when compared to the Graphite design, allowing for a shared Internet 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 is based on Motorola's PowerPC 855 processor and contained a fully functional original AirPort Card, which can be removed and used in any compatible Macintosh computer.

AirPort Extreme Base Station

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 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.

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. 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 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 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.. However, this seems to be contradicted by Apple.

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.

On October 20, 2009, Apple unveiled an updated AirPort Extreme base station with antenna improvements.

On June 21, 2011, Apple unveiled an updated AirPort Extreme base station, referred to as AirPort Extreme 802.11n (5th Generation).

The detailed table of output power comparison between the previous model MC340LL/A and the current model MD031LL/A can be seen below:

AirPort Express

The AirPort Express is a simplified and compact AirPort Extreme base station. It allows up to 10 networked users, and includes a feature called AirTunes (predecessor to AirPlay). The original version (M9470LL/A, model A1084) was introduced by Apple on June 7, 2004, and includes an analog–optical audio mini-jack output, a USB port for remote printing or charging the iPod (iPod Shuffle only), 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, model A1264) featuring the faster 802.11 Draft-N draft specification and operation in either of the 2.4 GHz and 5 GHz bands was introduced by Apple on March 17, 2008 with almost all other features identical. The revised unit includes an 802.11a/n (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. Up to 10 wireless units can connect to this AirPort Express.

Both versions allow you to extend the range of a network, or to join as a dedicated printer and audio server.

To use the Airport Express, the user takes an Ethernet network cable which is used to connect the ADSL modem (the internet source) to the Ethernet port on the Airport Express. This causes the Airport Express to become a WiFi signal emitter.

An often overlooked feature of the AirPort Express is that its 3.5mm stereo mini-jack connection also functions as a TOSLINK optical digital connector when used with a Mini-TOSLINK adaptor, allowing connection to an external DAC or amplifier with internal DAC. This allows CDs ripped in iTunes in Apple Lossless format to stream to the AirPort Express which will in turn output a bitstream which is bit-for-bit identical to the original CD (provided volume adjustments, Sound Check and Sound Enhancer are switched off for playback in iTunes). DTS-encoded CDs ripped to Apple Lossless audio files which decode as digital noise in iTunes will play back correctly when the AirPort Express is connected via TOSLINK to a DTS-compatible amplifier–decoder.

AirPlay

AirPlay (previously called 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 or Apple TV. AirPlay uses the Remote Audio Output Protocol RAOP. On the November 22, 2010, Apple released iOS 4.2.1, bringing AirPlay to compatible iOS devices.

Time Capsule

Time Capsule is a version of AirPort Extreme with a built-in hard-drive currently coming in either 2 TB or 3 TB sizes, with a previous version having 1 TB or 500 GB. It features a built-in design that, when used with Time Machine in Mac OS X Leopard, automatically makes incremental data backups. Acting as a wireless file server, Time Capsule can serve to back up multiple Macs. It also includes all AirPort Extreme (802.11 Draft-N) functionality.

On March 3, 2009, the Time Capsule was updated with simultaneous dual-band 802.11 Draft-N capability, remote AirPort Disk accessibility through Back to My Mac, and the ability to broadcast a guest network at the same time as an existing network.

On October 20, 2009, Apple unveiled the updated Time Capsule with antenna improvements resulting in wireless performance gains of both speed and range. Also stated is a resulting performance improvement/time reduction on Time Capsule backups of up to 60%.

During June, 2011, Apple unveiled the updated Time Capsule with a higher capacity 2 TB and 3 TB.

Time Capsules demonstrated to have a ventilation and cooling flaw in their design, resulting in a high failure rate after about 18 months of use. Apple has since replaced faulty units and corrected the problem.

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.

AirPort 802.11b Card

The original model, known as simply AirPort Card, was a re-branded Lucent WaveLAN/Orinoco 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/Orinoco Gold card). An AirPort card adapter is required to use this card in the slot loading iMacs.

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.

The AirPort Extreme (802.11g) card was discontinued in January 2009.

Integrated AirPort Extreme 802.11a/b/g and /n cards

As 802.11g 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. The particular brand and model of card has changed over the years; in early models, it was Atheros brand, while since late 2008 they have been Broadcom cards. This distinction is mostly of concern to those who run other operating systems such as Linux on MacBooks, as different cards require different device drivers.

MacBook Air Mid 2011 13" and MacBook Air Late 2011 (11", A1370 and 13", Model A1369 ) both use Broadcom BCM943224PCIEBT2 wifi card (main chip BCM43224: 2x2 2.4 GHz and 5 GHz).

In early 2007, Apple announced that most Intel Core 2 Duo-based Macs, which had been shipping since November 2006, already included AirPort Extreme cards compatible with the draft-802.11 Draft-N specification. Apple also offered an application to enable 802.11 Draft-N functionality on these Macs for a fee of $1.99, or free with the purchase of an AirPort Extreme base station.

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. The Network Utility application located in Applications → Utilities can be used to identify the model and supported protocols of an installed AirPort card.

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.

AirPort Disk

An AirPort Disk is essentially a hard disk connected to an AirPort Extreme Base Station or Time Capsule (though AirPort Express does not support it). AirPort Disks can be accessed from Windows and Linux as well as Mac OS X. The AirPort Extreme uses the SMB/CIFS protocol for FAT volumes, and both SMB/CIFS and AFP for HFS+ partitions. AirPort Extreme Base Stations do not support NTFS or exFAT volumes.

It should be noted that although Windows does not support the HFS+ (Mac OS Extended) file system when directly connected to an HFS+ volume (unless a third-party filesystem driver or program is used), a HFS+ volume on an AirPort Disk can be easily accessed from Windows. This is because the AirPort Extreme uses the SMB/CIFS protocol to allow access to the disk, and hence access from Windows is filesystem-independent. Therefore HFS+ is a viable option for Windows as well as OS X users, and more flexible than FAT32 as the latter has a 4GiB file size limit.

Recent firmware versions cause the internal disk and any external USB drives to sleep after periods of time as short as 2 minutes.

See also

Notes

External links






Retrieved from : http://en.wikipedia.org/wiki/AirPort

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