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AirPort is the name given to a series of products by Apple Inc. using the (Wi-Fi) protocols (802.11b, 802.11g, 802.11n and 802.11ac). These products comprise a number of wireless routers and wireless cards. The AirPort Extreme name was originally intended to signify the addition of the 802.11g protocol to these products. In Japan, the line of products is marketed under the brand AirMac〔(【引用サイトリンク】title= アップル – AirMac Express )〕 due to previous registration by I-O Data. ==Overview== AirPort debuted on July 21, 1999 at Macworld New York, 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.〔(Apple Introduces New AirPort Extreme with 802.11 Draft-N ), Apple.com, retrieved 1/9/07.〕 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)''. 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. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「AirPort」の詳細全文を読む スポンサード リンク
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