UltraSPARC T2

From Wikipedia, the free encyclopedia

Sun Microsystems' UltraSPARC T2 microprocessor, is a multithreading, multi-core CPU. It is the successor to the UltraSPARC T1. The chip is sometimes referred to by the codename Niagara II. Sun plans to start selling servers with the T2 processor in Q3 2007.



New Features
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The T2 is a commodity derivative of the UltraSPARC series of microprocessors, targeting internet workloads in computers, storage and networking devices. The processor, manufactured in 65 nm, is available with eight CPU cores, and each core is able to handle eight threads concurrently. Thus the processor is capable of processing up to 64 concurrent threads. Other new features include:

-Speed bump for each thread, increased to 1.4 GHz from 1.2 GHz
-one PCI Express port (x8 1.0)
-two 10 Gigabit Ethernet ports with packet classification and filtering
-the L2 cache size increased to 4 MB (8-banks, 16-way associative)
-improved thread scheduling and instruction prefetching to achieve higher single-threaded performance
-two integer ALUs per core instead of one, each one being shared by a group of four threads
-one floating point unit per core, up from just one FPU per CPU
-eight encryption engines (instead of just one in T1), with each supporting DES, 3DES, AES, RC4, SHA1, SHA256, MD5, RSA-2048, ECC, CRC32
-four dual-channel FBDIMM memory controllers
The UltraSPARC T2 is the first major processor whose blueprints are available under a free software license, namely the GPL.

Virtualization
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Like the T1, the T2 also supports the Hyper-Privileged execution mode. The SPARC Hypervisor runs in this mode, and it can partition a T2 system into 64 Logical Domains, each of which can run an operating system instance.

Tape-Out
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On April 12, 2006, Sun announced the tape-out completion of the T2. It also disclosed that under the same power envelope, the T2 will deliver twice the performance of the T1 when running transactional workload.

Announcement webcast Sun announced the UltraSPARC T2 on 7 August 2007. It is now being billed "The world's fastest microprocessor."

Performance Improvement: T2 vs. T1
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-Integer throughput and throughput/watt (>2x improvement)
-Integer single-thread performance (>1.4x improvement)
-Better floating-point throughput (>10x improvement)
-Better floating-point single-thread performance (>5x improvement)

Power consumption
-----------------------------------------------------
Peak power consumption can go as high as 123 watts, but the T2 typically consumes 95 watts during nominal system operation. This is up from 72 watts from the T1, but Sun explains that this is due to a higher degree of system integration onto the chip.

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iPhone

From Wikipedia, the free encyclopedia


The iPhone is a multimedia and Internet-enabled quad-band GSM EDGE-supported mobile phone designed and sold by Apple Inc. The iPhone's functions include those of a camera phone and a multimedia player, in addition to text messaging and visual voicemail. It also offers Internet services including e-mail, web browsing, and local Wi-Fi connectivity. User input is accomplished via a multi-touch screen with virtual keyboard and buttons.

The iPhone has been available since June 29, 2007 in the United States from Apple Retail Stores, the Apple Online Store, and from AT&T Mobility, formerly Cingular Wireless, for a contracted price of US$499 for the 4 GB model and US$599 for the 8 GB model.


Features
---------------------------------
Apple has released a video explaining many of iPhone's features through a series of demonstrations.

Touch screen
The 3.5 in liquid crystal display (320×480 px at 160 ppi) HVGA touch screen topped with optical-quality glass is specifically created for use with a finger, or multiple fingers for multi-touch sensing. Because the screen is a capacitive touch screen, no stylus is needed, nor can one be used. The requirement for bare skin to be used has caused concerns for users in areas with winter climates; gloves worn would then have to be removed to use the touchpad.

For text input, the device implements a virtual keyboard on the touchscreen. It has automatic spell checking, predictive word capabilities, and a dynamic dictionary that learns new words. The predictive word capabilities have been integrated with the dynamic virtual keyboard so that users will not have to be extremely accurate when typing—i.e. touching the edges of the desired letter or nearby letters on the keyboard will be predictively corrected when possible. The keys are somewhat larger and spaced further apart when in landscape mode (currently, only using Safari). Reviewers, writers and analysts have pointed out several areas in which the iPhone falls short. The virtual keyboard has been considered its chief weakness and a risk for Apple. David Pogue of The New York Times and Walt Mossberg of The Wall Street Journal both tested the iPhone for two weeks and found learning to use it initially difficult, although eventually usable. Pogue stated use was "frustrating" and "text entry is not the iPhone’s strong suit" but Mossberg considered the keyboard a "nonissue." Both found that the typo-correcting feature of the iPhone was the key to using the virtual keyboard successfully.


The iPhone varies from common desktop interfaces by using a direct manipulation model of scrolling. Where a typical desktop GUI achieves scrolling by using a scroll-arrow to push a view-window down and thus the content itself up (or the reverse, clicking up to move content down), the iPhone interface enables the user to move the content itself up or down by a touch-drag-lift motion of the finger, much as one would slide a playing card across a table. Additionally, the speed desired for scrolling is computed based on the speed and acceleration with which the drag motion is performed.

Scrolling through a long list works as if the list is pasted on the surface of a wheel: the wheel can be "spun" by sliding a finger over the display. After the finger is lifted from the display the wheel continues to "spin" for a short moment before coasting down. In this way, the iPhone seems to simulate the physics of a real object, which, it is thought, should give a natural feel to the whole process.

The user interface also features other visual effects, such as horizontally sliding sub-selections and co-selections from right and left, vertically sliding system menus from the bottom (e.g. favorites, keyboard), and menus and widgets that turn around to allow settings to be configured on their back sides.

The photo album and web page magnifications are examples of multi-touch sensing. It is possible to zoom in and out of objects such as web pages and photos by respectively "unpinching" and "pinching" them, that is, placing two fingers (usually thumb and forefinger) on the screen and moving them farther apart or closer together as if stretching or squeezing the image. This scaling is done uniformly and proportionally based on the image in question so there is no distortion of the image itself, as would be the case if the image were actually stretched or squeezed.

One disadvantage of multi-touch with regards to AJAX web sites is that there is no mechanism for 'hovering' over a UI element. That is, there is no separate paradigm for indicating interest or focus on a portion of a web control other than clicking on it.

The iPhone's touch interface has been compared by some media to the HTC Touch, which also features a touchscreen designed for fingers, although it can also be used with a stylus and lacks multi-touch.

Other inputs
The display responds to three sensors: a proximity sensor that shuts off the display and touchscreen when the iPhone is brought near the face to save battery power and to prevent spurious inputs from the user's face and ears, an ambient light sensor that adjusts the display brightness which in turn saves battery power, and a 3-axis accelerometer, which senses the orientation of the phone and changes the screen accordingly. Web browsing and music playing support three orientations, while videos play in only one widescreen orientation.

A single "home" hardware button below the display brings up the main menu. Subselections are made via the touchscreen. The iPhone utilizes a full-paged display, with context-specific submenus at the top and/or bottom of each page, sometimes depending on screen orientation. Detail pages display the equivalent of a "Back" button to go up one menu.

The iPhone has three physical switches on its sides: sleep / wake, volume up / down, ringer on / off. All other multimedia and phone operations are done via the touch screen.

Phone
The iPhone allows conferencing, call holding, call merging, caller ID, and integration with other cellular network features and iPhone functions. For example, a playing song fades out when the user receives a call. Once the call is ended the music fades back in.

The iPhone includes a Visual Voicemail feature in conjunction with AT&T which allows users to view a list of current voicemail messages on-screen, without having to call into their voicemail. Unlike most other systems, messages can be listened to in a non-chronological order, by choosing messages from an on-screen list. AT&T modified their voicemail infrastructure to accommodate this new feature designed by Apple.

SMS messages are presented chronologically in a mailbox format similar to Mail, which places all text from recipients together with replies. Text messages are displayed in speech bubbles (similar to iChat) under each recipient's name.

Camera
The iPhone features a built in 2.0 megapixel camera located on the back for still digital photos, but not video recording. It also includes software that allows the user to upload, view, and e-mail photos. The user zooms in and out of photos by "unpinching" and "pinching" them through the multi-touch interface. The software interacts with iPhoto on the Mac.

Multimedia
The layout of the music library differs from previous iPods, with the sections divided more clearly alphabetically, and with a larger font. Similar to previous iPods, the iPhone can sort its media library by songs, artists, albums, videos, playlists, genres, composers, podcasts, audiobooks, and compilations. The Cover Flow, like that on iTunes, shows the different album covers in a scroll-through photo library. Scrolling is achieved by swiping a finger across the screen.

Like the fifth generation iPods introduced in 2005, the iPhone can play video, allowing users to watch TV shows and films. Unlike other image-related content, video on the iPhone plays only in the landscape orientation, when the phone is turned sideways. A two-fingered tap is used to switch between the video's true wide-screen aspect ratio (with black bars on the top and bottom of the screen) and a zoomed mode (to fill the iPhone's screen).


Web connectivity
The iPhone has built-in Wi-Fi, with which it is able to access the World Wide Web (through a wireless network) via a modified version of the Safari web browser. The iPhone is also able to connect to the web through AT&T's EDGE network, but is not able to utilize AT&T's 3G/HSDPA network; Steve Jobs mentioned at the Keynote presentation that 3G support would be a future feature of a new version. The use of the EDGE network instead of 3G has been criticized by analysts. When the user is not in a Wi-Fi hot spot, the iPhone's network connection will use the older EDGE network, which, before the launch, reviewers found that the EDGE network was "excruciatingly slow," with the iPhone taking as long as 100 seconds to download the Yahoo! home page for the first time. Immediately before the launch the observed speed of the network increased to almost 200 kbit/s. This is probably due to the new "Fine EDGE" upgrades AT&T has been making to their network prior to the launch. There has also been some criticism stemming from the iPhone's inability to download iTunes content wirelessly.

The web browser displays full web pages as opposed to simplified pages as on most non-smartphones. The iPhone does not support Flash or Java technology. Web pages may be viewed in portrait or landscape mode and support automatic zooming by "pinching" or double-tapping images or text. The iPhone also has Bluetooth 2.x+EDR built in. It works with wireless earpieces that use Bluetooth technology.

An agreement between Apple and Google provides for access to a specially modified version of Google Maps—in map, local list, or satellite form, optimized for the iPhone, which also provides optional real-time traffic information. During the product's announcement, Jobs demonstrated this feature by searching for nearby Starbucks locations and then placing a prank call to one with a single tap. Google's ownership of YouTube means that viewing videos on the website can be achieved on the iPhone through a specialised application built into the system.

E-mail
The iPhone also features an HTML e-mail program, which enables the user to embed photos in an e-mail message. PDF, Microsoft Word, and Microsoft Excel attachments to mail messages can be viewed on the phone. Yahoo! is currently the only e-mail provider offering a free Push-IMAP e-mail service similar to that on a BlackBerry for the iPhone; IMAP and POP3 mail standards are also supported, including Microsoft Exchange. The iPhone will sync e-mail account settings over from Apple's own Mail application, Microsoft Outlook and Microsoft Entourage, or can be manually configured using the device's Settings tool. With the correct settings, the e-mail program can check many IMAP or POP3-enabled web based accounts such as Gmail, .Mac mail, and AOL.

OS X
Apple has confirmed that an optimized version of the Mac OS X operating system (without unnecessary components) runs on the iPhone, although differences between the operating system (OS X) running on Macs and the iPhone have not been officially explained. As iPhone's CPU is an ARM processor, the version of OS X that runs on iPhone differs from the desktop version in that code written in high-level programming languages is compiled to, and code written in assembly language is written in, instructions from the ARM instruction set architecture (ISA) instead of the x86 and PowerPC ISAs that the Mac version of OS X uses.

The operating system takes up about 700 MB of the device's total 4 or 8 GB storage. It will be capable of supporting bundled and future applications from Apple.

Apple intends to offer a smooth method for updating the iPhone's operating system, in a similar fashion to the way that Mac OS X and iPods are updated, and touts this as an advantage compared to other cell phones.

Widgets, similar to the ones available in Mac OS X v10.4's Dashboard, are included on the iPhone. They include Stocks and Weather widgets.

The iPhone's version of OS X includes the software component "Core Animation" which is responsible for the smooth animations used in its user interface. Core Animation has not yet been released for Macs, but will be part of Mac OS X v10.5.

The build of OS X on at least one iPhone is "OS X 1.0 (1A543a)", as seen in a crash log for the MobileMail application. The application apparently runs as the superuser.

Applications
There are several applications located on the "Home" screen. The YouTube application streams videos over Wi-Fi and/or EDGE after encoding them using QuickTime's H.264 codec, to which YouTube has converted about 10,000 videos. They are expected to convert the entire catalog by Fall 2007. As a result, the YouTube application on iPhone can currently only view a certain selection of videos from the site. Also, because YouTube displays videos using Flash, the iPhone can only view videos through the YouTube application as opposed to accessing the website using Safari.

At WWDC 2007 on June 11, 2007 Apple Inc. announced that the iPhone will support third party "applications" via the Safari web browser that share the look and feel of the iPhone interface. The applications must be created in Ajax or JavaScript to maintain device security. The iPhone cannot officially install full programs from anyone but Apple, although Steve Jobs has hinted that future third party applications are in development. Enthusiasts have demonstrated the possibility of unauthorized native code with a simple "Hello, World" program, as well as a fully functional terminal emulator.

Analysts also claim that iPhone lacks any type of firewall, which some experts claim is posing a data security risk. It is not confirmed by Apple or by independent analysts that used the actual device for tests that it doesn't have a firewall. Daniel Eran writes: "Dulaney doesn't know if the iPhone has a firewall, has no reason to suggest that its installation of OS X wouldn't offer a firewall, and offers no reasons why a mobile device would need a firewall anyway."

Platform support
The iPhone is compatible with Mac OS X version 10.4.10 or later, and 32-bit Windows XP or Vista. For each, the user must download the latest version of iTunes Version 7.3. The iPhone is not compatible with any 64-bit version of Windows such as Windows XP x64 or any 64-bit edition of Windows Vista.


Software updates
Apple has confirmed that software updates can be distributed to the iPhone device via iTunes. Security patches as well as new and improved features, such as a mobile chat client, Flash support, and voice recording, may be released in this fashion. The first iPhone software update was released on July 31, 2007.

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Microformat

From Wikipedia, the free encyclopedia


In web development, a microformat (sometimes abbreviated μF or uF) is a way of adding simple semantic meaning to human-readable content which is otherwise, from a machine's point of view, just plain text. They allow data items such as events, contact details or locations, on HTML (or XHTML) web pages, to be meaningfully detected and the information in them to be extracted by software, and indexed, searched for, saved or cross-referenced, so that it can be reused or combined.

More technically, they are items of semantic mark up, using just standard (X)HTML with a set of common class-names. They are open and available, freely, for anyone to use.

Current microformats allow the encoding and extraction of events, contact information, social relationships, and so on. More are being developed. Version 3 of the Firefox browser, as well as version 8 of Internet Explorer are expected to include native support for microformats.



Principles

(X)HTML standards allow for semantics to be embedded and encoded within them. This is done using specific HTML attributes:

class
rel
rev
For example, 52.48,-1.89 is a pair of numbers which may be understood, from their context, to be a set of geographic coordinates. By wrapping them in spans (or other HTML elements) with specific class names (in this case part of the geo microformat specification):

<span class="geo"><span class="latitude">52.48</span>, <span class="longitude">-1.89</span></span>

machines can be told exactly what each value represents, and can then index it, look it up on a map, export it to a GPS device, etc.


Uses of microformats
-------------------------------------
Using microformats within HTML code provides additional formatting and semantic data that can be used by applications. These could be applications that collect data about on-line resources, such as web crawlers, or desktop applications such as e-mail clients or scheduling software.

Several browser extensions, such as Operator, provide the ability to detect microformats within an HTML document and export them into formats compatible with contact management and calendar utilities, such as Microsoft Outlook.

Microsoft expressed a desire to incorporate Microformats into upcoming projects; as have other software companies.

In Wikipedia - and more generally in MediaWiki - microformats are used as part of templates like {{coord}} for example.

Creation of microformats
----------------------------------------
Most of the existing microformats were created at the microformat wiki and associated mailing list, by a process of gathering examples of web publishing behaviour, then codifying it. Some other microformats (such as rel=nofollow and unAPI have been proposed, or developed, elsewhere.

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Intel Core 2

From Wikipedia, the free encyclopedia


The Core 2 brand refers to a range of Intel's mobile and desktop 64-bit dual-/quad-core x86 CPUs with the Core microarchitecture, which evolved from the 32-bit dual-core Yonah mobile processor. The Yonah comprised two interconnected single cores (the Pentium M branded microprocessor derivatives) coupled as a single die silicon chip (IC). The Core 2 marked a relegation of the Intel's Pentium brand to a lower-end market, and a reunification of Intel's notebook and desktop brand names, previously divided into the Pentium M and Pentium 4 lines.

The Core 2 brand was launched on July 27, 2006, comprising Duo (dual-core), Quad (quad-core), and Extreme (dual- or quad-core CPUs with higher speeds and unlocked multiplier) branches. The brand covers processors based on various cores; "Conroe" and "Allendale" (dual-core for higher- and lower-end desktop use, respectively), "Merom" (dual-core for notebooks), "Kentsfield" (quad-core for desktops), and their variants named "Penryn" (dual-core for notebooks), "Wolfdale" (dual-core for desktops) and "Yorkfield" (quad-core for desktops). Although the "Woodcrest", "Clovertown" and the upcoming "Tigerton" core CPUs for servers and workstations are also based on Core architecture, they are marketed under the Xeon brand. The first Core 2 Duo processors were fabricated on 300 mm wafers using a 65 nm manufacturing process.


Unlike the NetBurst architecture of Pentium 4 or Pentium D branded processors, the Core architecture does not stress extremely high clock speeds, but rather improvements in the processor's usage of both available clock cycles and power. This translated into more efficient decoding stages, execution units, caches, and buses, etc, reducing the Core 2 CPU's power consumption, while enhancing their processing capacity. With a TDP of up to only 65 W, the Core 2 dual-core Conroe consumed only half the power of some of the higher end dual-core Pentium D branded desktop chips with a TDP of up to 130 W (a high TDP requires many noisy cooling fans or a more expensive noiseless cooling system) and was more capable compared to them.


Intel Core 2 processors featured Intel 64 (also known as EM64T), Virtualization Technology (except T5500 or lower end E4x00), Execute Disable Bit, and SSE3. Core 2 also introduced SSSE3, Trusted Execution Technology, Enhanced SpeedStep, and Active Management Technology (iAMT2).

Typically for CPUs, the Core 2 Duo E4000/E6000, Core 2 Quad Q6600, Core 2 Extreme X6800, QX6700 and QX6800 CPUs were affected by bugs, but apparently minor.

Current processor cores
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Conroe
The first Intel Core 2 Duo processor cores, code-named Conroe and given the Intel product code 80557, were launched on July 27, 2006 at Fragapalooza, a yearly gaming event in Edmonton, Alberta, Canada. These processors are built on a 65 nm process and are intended for desktops, replacing the Pentium 4 and Pentium D. Intel has claimed that Conroe provides 40% more performance at 40% less power compared to the Pentium D. All Conroe processors are manufactured with 4 MiB L2 cache; however, for marketing purposes, the E6300 and E6400 versions based on this core have half their cache disabled, leaving them with only 2 MiB of usable L2 cache.

The lower end E6300 (1.86 GHz) and E6400 (2.13 GHz), both with a 1066 MT/s FSB, were released on July 27, 2006. Traditionally, CPUs of the same family with less cache simply have the unavailable cache disabled, since this allows parts that fail quality control to be sold at a lower rating. As yields improve, they may be replaced with versions that only have the cache amount needed on the die, to bring down manufacturing cost. At launch time, Intel's prices for the Core 2 Duo E6300 and E6400 processors were US$183 and US$224 each in quantities of 1000. Conroe CPUs have improved capabilities over previous models with similar processor speeds. According to reviews, the larger 4 MiB L2 cache vs. the smaller 2 MiB L2 cache at the same frequency and FSB can provide a 0–9% performance gain with certain applications and 0–16% performance gain with certain games. The higher end Conroe processors are labeled as the E6600 and E6700 Core 2 Duo models, with the E6600 clocked at 2.4 GHz and the E6700 clocked at 2.67 GHz. The family has a 1066 MT/s front side bus, 4 MiB shared L2 cache, and 65 watts TDP. These processors have been tested against AMD's current top performing processors (Athlon 64 FX Series), which were, until this latest Intel release, the fastest CPUs available. Conroe chips also experience much lower heat output compared to their predecessors — a benefit of the new 65 nm technology. At launch time, Intel's prices for the Core 2 Duo E6600 and E6700 processors were US$316 and US$530, respectively, each in quantities of 1000.

E6320 and E6420 Conroe CPUs at 1.86 and 2.13 GHz respectively were launched on April 22, 2007 featuring a full 4 MiB of cache and are considered Conroes.

Intel released four additional Core 2 Duo Processors on July 22nd, 2007. The release coincided with that of the Intel Bearlake (x3x) chipsets. The new processors are named Core 2 Duo E6540, E6550, E6750, and E6850. Processors with a number ending in "50" have a 1333 MT/s FSB. The processors all have 4 MiB of L2 cache. Their clock frequency is similar to that of the already released processors with the same first two digits (E6600, E6700, X6800). An additional model, the E6540, was launched with specifications similar to the E6550 but lacking Intel Trusted Execution Technology and vPro support. These processors are slated to compete with AMD's Stars processor line and are therefore priced below corresponding processors with a 1066 MT/s FSB.

Conroe XE
The Core 2 Extreme was officially released on July 29, 2006. However some retailers appeared to have released it on July 13, 2006, though at a higher premium. The less powerful E6x00 models of Core 2 Duo were scheduled for simultaneous release with the X6800, which are both available at this time. It is powered by the Conroe XE core and replaces the dual-core Pentium Extreme Edition processors. Core 2 Extreme has a clock speed of 2.93 GHz and a 1066 MT/s FSB, although it was initially expected to be released with a 3.33 GHz and 1333 MT/s. The TDP for this family is 75–80 watts. At full load the X6800 does not exceed 45 °C (113 °F), and with SpeedStep enabled the average temperature of the CPU when idle is essentially that of the ambient atmosphere.

At launch time, Intel's price for the Core 2 Extreme X6800 was US$999 each in quantities of 1000. Like the desktop Core 2 Duo, it has 4 MiB of shared L2 cache available. This means that the only major difference between the regular Core 2 Duo and Core 2 Extreme is the clock speed and unlocked multiplier, usual advantages of the "Extreme Edition." The unlocked upward multiplier is of use to enthusiasts which allow the user to set the clockspeed higher than shipping frequency without modifying the FSB unlike mainstream Core 2 Duo models which are downward unlocked only.

Allendale
There was contention as to whether the previously-available low-end Core 2 Duo desktop processors (E6300, at 1.86 GHz and E6400, at 2.13 GHz, both with 2 MiB L2 cache) are specimens of the Allendale core. Prior to Q1 2007, all E6300 and E6400 processors released were Conroe (4 MiB L2 cache) cores with half their L2 cache disabled. The Allendale core, manufactured with 2 MiB L2 cache in total, offers a smaller die size and therefore greater yields.

Quoted from The Tech Report:

You'll find plenty of sources that will tell you the code name for these 2 MB Core 2 Duo processors is "Allendale," but Intel says otherwise. These CPUs are still code-named "Conroe," which makes sense since they're the same physical chips with half of their L2 cache disabled. Intel may well be cooking up a chip code-named Allendale with 2 MB of L2 cache natively, but this is not that chip.

Another difference between the premium E6000 series (Conroe core) or (Allendale core) and the E4000 series (Allendale core) is the front side bus clock rating. The E4000 series are rated to run on a quad-pumped 200 MHz front side bus ("800 MT/s") while the E6000 series are rated to run on a quad-pumped 266 MHz front side bus ("1066 MT/s"). The E4000 series also lack support for Intel VT-x instructions.

The currently available Core 2 Duo E4300 only uses an Allendale core, released on January 21, 2007. The Allendale processors use a smaller mask with only 2 MiB of cache, thereby increasing the number of chips per wafer. Allendale processors are produced in the LGA775 form factor, on the 65 nm process node. It is unclear and a matter of contention whether the E6300 and E6400 models are still Conroe processors with half their L2 cache disabled or Allendale processors. It is possible that the E6300 and E6400 models can be both Allendale and Conroe, differentiated by the L2 and B2 steppings respectively.

Initial list price per processor in quantities of one thousand for the E4300 was US$163. A standard OEM price was US$175, or US$189 for a retail package. Price cuts were enacted on April 22, 2007, when the E4400 was released at $133 and the E4300 dropped to $113. Allendale processors with half their L2 cache disabled were released in mid-June 2007 under the Pentium Dual-Core brand name.

On July 22nd, 2007, an E4500 Allendale was launched, phasing out the E4300 model. This was accompanied by a price cut for the E4400 model.


Merom
Merom, the first mobile version of the Core 2, was officially released on July 27, 2006 but quietly began shipping to PC manufacturers in mid-July alongside Conroe. Merom is Intel's premier line of mobile processors, with largely the same features as Conroe, but with more emphasis on low power consumption to enhance notebook battery life. Merom-based Core 2 Duo provides 20% more performance yet maintains the same battery life as the Yonah-based Core Duo. Merom is the first Intel mobile processor to feature Intel 64 architecture.

The first version of Merom is "drop-in" compatible with Napa platform for Core Duo, requiring at most a motherboard BIOS update. It has a similar thermal envelope of 34 W and the same 667 MT/s FSB rate. Merom features 4 MiB L2 cache (budget T5xxx models have only 2 MiB L2 cache).

A second wave of Merom processors featuring an 800 MT/s FSB and using the new Socket P was launched on May 9, 2007. These chips are part of Santa Rosa platform. Low voltage versions were also released on May 9, 2007.

Merom (מרום) is the Hebrew word for a higher plane of existence or a level of heaven, BaMerom (במרום) means "in the heavens". The name was chosen by the Intel team in Haifa, Israel, who designed this processor.

See the Merom section of "List of Intel Core 2 microprocessors" for a list of Merom processors.

Kentsfield
The Kentsfield was the first Intel desktop quad core CPU branded as Core 2 (and Xeon for lower-end servers and workstations). The top-of-the-line Kentsfields were Core 2 Extreme models numbered QX6xx0, while the mainstream ones branded Core 2 Quad were numbered Q6xx0. All of them featured two 4 MB L2 caches. The mainstream Core 2 Quad Q6600, clocked at 2.4 GHz, was launched on January 8, 2007 at US$851 (reduced to US$530 on April 7, 2007, and to US$266 on July 22, 2007). July 22, 2007 marked the release of the next Core 2: Quad Q6700 and Extreme QX6850 Kentsfields at US$530 and US$999 respectively, and also price reduction of Core 2: Quad Q6600 and Extreme QX6800 Kentsfields to US$266 and US$999 respectively.

Kentsfield, like the Pentium D Presler, comprised two separate silicon dies. Each of Kentsfield's two dies was dual-core with the Core architecture, as did each die constituting alone every Core 2's dual-core only CPU. Hence, the max. power consumption (TDP) of the Kensfield (QX6800 - 130 watts, QX6700 - 130 W,Q6600 - 95 W) was approx. double of its similarly clocked Core 2 Duo counterpart. For example, the QX6700 consisted of two E6700 chips connected together by a 1066 MT/s FSB on one MCM, resulting in lower costs but less bandwidth to the northbridge. The Kentsfield was one socket processor sitting in a LGA775 socket, as well as Core 2 Duo (AMD Quad FX consisted of two dual-core processors in two separate sockets on one motherboard with a 2 x 125 W= 250 W TDP).

A quad-core CPU, like the Kentsfield, processes very well with multi-threaded applications (typical for video editing, ray-tracing, or rendering), where its processing ability may approach double that of each of its halves comprising the equally clocked dual-core CPU. Similarly, Pentium D Presler had two dice in one package. A two-die CPU, however, can rarely double the processing ability of each of its constituent halves (e.g. the Kentsfield rarely doubles the ability of the Conroe), due to a loss of performance resulting from connecting them (i.e. sharing the narrow memory bandwidth, and operating system overhead of handling twice as many cores and threads).

Single or dual-threaded applications alone, including most games, do not benefit from the second pair of cores of a quad-core CPU over an equally clocked dual-core CPU. For example, with no increase in FSB speed and a mild reduction in processor frequency of the quad-core Extreme QX6700 over the older dual-core Extreme X6800, overall performance of the Kentsfield (QX6700) for those applications does not improve. Nevertheless, the simultaneous use of several processor-intensive single/dual-threaded applications on a quad-core CPU will generally lead to a dramatic overall performance increase over an equally clocked dual-core CPU. A quad-core CPU is useful also to run the both client and server processes of a game without noticeable lag in either thread, as each instance (up to four) could be running on a different core.

Kentsfield XE
The first Kentsfield, named Core 2 Extreme QX6700 (product code 80562) and clocked at 2.67 GHz, was released on November 2, 2006 at US$999. It was the first x86 quad-core processor ever, featured the Kentsfield XE core, and complemented the Core 2 Extreme X6800 dual-core processor based on the Conroe XE core. The CPUs with the Kentsfield XE core had the highest and unlocked multipliers like their Extreme predecessors. On April 8, 2007, a new top Kentsfield XE - the Core 2 Extreme QX6800 - was released within the 135 W TDP thermal envelope, and clocked at 2.93 GHz. It went to high end OEM-only systems at US$1,199. On July 22, 2007, the new champ Core 2 Extreme QX6850 arrived, clocked at 3.0 GHz, with a faster 1.33 GHz FSB, and at US$999 - a typical price for a top Kentsfield XE CPU.

The formerly available Core 2 Extreme QX6700 was relaunched on July 22nd, 2007 as the Core 2 Quad Q6700, clocked at 2.66 GHz, but it consumes less power than QX6700. The price of the Q6600 has been dropped to US$266 on July 22nd, 2007.

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RSS

From Wikipedia, the free encyclopedia

RSS (which, in its latest format, stands for "Really Simple Syndication") is a family of web feed formats used to publish frequently updated content such as blog entries, news headlines or podcasts. An RSS document, which is called a "feed", "web feed", or "channel", contains either a summary of content from an associated web site or the full text. RSS makes it possible for people to keep up with their favorite web sites in an automated manner that's easier than checking them manually.

RSS content can be read using software called a "feed reader" or an "aggregator." The user subscribes to a feed by entering the feed's link into the reader or by clicking an RSS icon in a browser that initiates the subscription process. The reader checks the user's subscribed feeds regularly for new content, downloading any updates that it finds.

The initials "RSS" are used to refer to the following formats:

Really Simple Syndication (RSS 2.0)
RDF Site Summary (RSS 1.0 and RSS 0.90)
Rich Site Summary (RSS 0.91)
RSS formats are specified using XML, a generic specification for the creation of data formats.



Incompatibilities
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As noted above, there are several different versions of RSS, falling into two major branches (RDF and 2.*). The RDF, or RSS 1.* branch includes the following versions:

-RSS 0.90 was the original Netscape RSS version. This RSS was called RDF Site Summary, but was based on an early working draft of the RDF standard, and was not compatible with the final RDF Recommendation.
-RSS 1.0 is an open format by the RSS-DEV Working Group, again standing for RDF Site Summary. RSS 1.0 is an RDF format like RSS 0.90, but not fully compatible with it, since 1.0 is based on the final RDF 1.0 Recommendation.
-RSS 1.1 is also an open format and is intended to update and replace RSS 1.0. The specification is an independent draft not supported or endorsed in any way by the RSS-Dev Working Group or any other organization.
The RSS 2.* branch (initially UserLand, now Harvard) includes the following versions:

-RSS 0.91 is the simplified RSS version released by Netscape, and also the version number of the simplified version championed by Dave Winer from Userland Software. The Netscape version was now called Rich Site Summary, this was no longer an RDF format, but was relatively easy to use. It remains the most common RSS variant.
-RSS 0.92 through 0.94 are expansions of the RSS 0.91 format, which are mostly compatible with each other and with Winer's version of RSS 0.91, but are not compatible with RSS 0.90. In all Userland RSS 0.9x specifications, RSS was no longer an acronym.
-RSS 2.0.1 has the internal version number 2.0. RSS 2.0.1 was proclaimed to be "frozen", but still updated shortly after release without changing the version number. RSS now stood for Really Simple Syndication. The major change in this version is an explicit extension mechanism using XML Namespaces.
For the most part, later versions in each branch are backward-compatible with earlier versions (aside from non-conformant RDF syntax in 0.90), and both versions include properly documented extension mechanisms using XML Namespaces, either directly (in the 2.* branch) or through RDF (in the 1.* branch). Most syndication software supports both branches. Mark Pilgrim's article "The Myth of RSS Compatibility" discusses RSS version compatibility in more detail.

The extension mechanisms make it possible for each branch to track innovations in the other. For example, the RSS 2.* branch was the first to support enclosures, making it the current leading choice for podcasting, and as of mid-2005 is the format supported for that use by iTunes and other podcasting software; however, an enclosure extension is now available for the RSS 1.* branch, mod_enclosure. Likewise, the RSS 2.* core specification does not support providing full-text in addition to a synopsis, but the RSS 1.* markup can be (and often is) used as an extension. There are also several common outside extension packages available, including a new proposal from Microsoft for use in Internet Explorer 7.

The most serious compatibility problem is with HTML markup. Userland's RSS reader—generally considered as the reference implementation—did not originally filter out HTML markup from feeds. As a result, publishers began placing HTML markup into the titles and descriptions of items in their RSS feeds. This behavior has become widely expected of readers, to the point of becoming a de facto standard, though there is still some inconsistency in how software handles this markup, particularly in titles. The RSS 2.0 specification was later updated to include examples of entity-encoded HTML, however all prior plain text usages remain valid.

Atom
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In reaction to recognized issues with RSS (and because RSS 2.0 is frozen), a third group began a new syndication specification, Atom, in June 2003. Their work was later adopted by the Internet Engineering Task Force (IETF) leading to the publication of a specification (RFC 4287) for the Atom Format in 2005. Work on the Atom Publishing Protocol, a standards-based protocol for posting to publishing tools is ongoing.

The relative benefits of Atom in comparison to the two RSS branches are a matter of debate within the Web-syndication community. Supporters of Atom claim that it improves on RSS by relying on standard XML features, by specifying a payload container that can handle many different kinds of content unambiguously, and by having a specification maintained by a recognized standards organization. Critics claim that Atom unnecessarily introduces a third branch of syndication specifications, further confusing the marketplace.

Atom aims to define both a syntax and a protocol for updating user blogs and thus goes beyond the simple remit of RSS. While this is appealing to many users, particularly those in the blogging community, it has been met with resistance in the professional community (mainly publishers) due to its lack of extensibility.

For a comparison of Atom 1.0 to RSS 2.0 see Atom Compared to RSS 2.0.

BitTorrent and RSS
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The peer-to-peer application BitTorrent has also announced support for RSS. Such feeds (also known as Torrent/RSS-es or Torrentcasts) will allow client applications to download files automatically from the moment the RSS reader detects them (also known as Broadcatching). Most common BitTorrent clients already offer RSS support

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WiMAX

From Wikipedia, the free encyclopedia


WiMAX, the Worldwide Interoperability for Microwave Access, is a telecommunications technology aimed at providing wireless data over long distances in a variety of ways, from point-to-point links to full mobile cellular type access. It is based on the IEEE 802.16 standard, which is also called WirelessMAN. WiMAX allows a user, for example, to browse the Internet on a laptop computer without physically connecting the laptop to a wall jack. The name WiMAX was created by the WiMAX Forum, which was formed in June 2001 to promote conformance and interoperability of the standard. The forum describes WiMAX as "a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL."



Uses
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The bandwidth and reach of WiMAX make it suitable for the following potential applications:

-Connecting Wi-Fi hotspots with each other and to other parts of the Internet.
-Providing a wireless alternative to cable and DSL for last mile (last km) broadband access.
-Providing high-speed data and telecommunications services.
-Providing a diverse source of Internet connectivity as part of a business continuity plan. That is, if a business has a fixed and a wireless Internet connection, especially from unrelated providers, they are unlikely to be affected by the same service outage.
-Providing nomadic connectivity.

Broadband access
Many companies are closely examining WiMAX for "last mile" connectivity at high data rates. The resulting competition may bring lower pricing for both home and business customers, or bring broadband access to places where it has been economically unavailable. Prior to WiMAX, many operators have been using proprietary fixed wireless technologies for broadband services.

WiMAX access was used to assist with communications in Aceh, Indonesia, after the tsunami in December 2004. All communication infrastructures, other than HAM Radio in the area were destroyed making the survivors unable to communicate with people outside the disaster area and vice versa. WiMAX provided broadband access that helped regenerate communication to and from Aceh.

Subscriber units
WiMAX subscriber units are available in both indoor and outdoor versions from several manufacturers. Self-install indoor units are convenient, but radio losses mean that the subscriber must be significantly closer to the WiMAX base station than with professionally installed external units. As such, indoor installed units require a much higher infrastructure investment as well as operational cost (site lease, backhaul, maintenance) due to the high number of base stations required to cover a given area. Indoor units are comparable in size to a cable modem or DSL modem. Outdoor units are roughly the size of a laptop PC, and their installation is comparable to a residential satellite dish.

With the advent of mobility ("16e"), there is an increasing focus on portable units. This includes handsets (similar to cellular smartphones) and PC peripherals (PC Cards or USB dongles). In addition, there is much emphasis from operators on consumer electronics devices (games terminals, MP3 players and the like); it is notable this is more similar to WiFi than 3G cellular technologies.

Mobile applications
Some cellular companies are evaluating WiMAX as a means of increasing bandwidth for a variety of data-intensive applications; Sprint Nextel announced in mid-2006 that it would invest about US$ 3 billion in a WiMAX technology buildout over the next few years.

In line with these possible applications is the technology's ability to serve as a high bandwidth "backhaul" for Internet or cellular phone traffic from remote areas back to an Internet backbone. Although the cost per user/point of WiMAX in a remote application will be higher, it is not limited to such applications, and may be an answer to reducing the cost of T1/E1 backhaul as well. Given the limited wired infrastructure in some developing countries, the costs to install a WiMAX station in conjunction with an existing cellular tower or even as a solitary hub are likely to be small in comparison to developing a wired solution. Areas of low population density and flat terrain are particularly suited to WiMAX and its range. For countries that have skipped wired infrastructure as a result of prohibitive costs and unsympathetic geography, WiMAX can enhance wireless infrastructure in an inexpensive, decentralized, deployment-friendly and effective manner.

Standards
------------------------------------
The current WiMAX incarnation, Mobile WiMAX, is based upon IEEE Std 802.16e-2005, approved in December 2005. It is an amendment of IEEE Std 802.16-2004 and so the actual standard is 802.16-2004 as amended by 802.16e-2005 - the specifications need to be read together to understand them.

IEEE Std 802.16-2004 addresses only fixed systems. It replaced IEEE Standards 802.16-2001, 802.16c-2002, and 802.16a-2003.

IEEE 802.16e-2005
IEEE 802.16e-2005 improves upon IEEE 802.16-2004 by:

-Scaling of the Fast Fourier Transform (FFT) to the channel bandwidth in order to keep the carrier spacing constant across different channel bandwidths (1.25-20 MHz). Constant carrier spacing results in a higher spectrum efficiency in wide channels, and a cost reduction in narrow channels. Also known as Scalable OFDMA (SOFDMA).
-Improving NLOS coverage by utilizing advanced antenna diversity schemes, and hybrid-Automatic Retransmission Request (hARQ)
-Improving capacity and coverage by introducing Adaptive Antenna Systems (AAS) and Multiple Input Multiple Output (MIMO) technology
-Increasing system gain by use of denser sub-channelization, thereby improving indoor penetration
-Introducing high-performance coding techniques such as Turbo Coding and Low-Density Parity Check (LDPC), enhancing security and NLOS performance
-Introducing downlink sub-channelization, allowing administrators to trade coverage for capacity or vice versa
-Enhanced Fast Fourier Transform algorithm can tolerate larger delay spreads, increasing resistance to multipath interference
-Adding an extra QoS class (enhanced real-time Polling Service) more appropriate for VoIP applications.
-Adding support for mobility (soft and hard handover between base stations). This is seen as one of the most important aspects of 802.16e-2005, and is the very basis of 'Mobile WiMAX'.
802.16d vendors point out that fixed WiMAX offers the benefit of available commercial products and implementations optimized for fixed access. It is a popular standard among alternative service providers and operators in developing areas due to its low cost of deployment and advanced performance in a fixed environment. Fixed WiMAX is also seen as a potential standard for backhaul of wireless base stations such as cellular, WiFi or even Mobile WiMAX.

SOFDMA (used in 802.16e-2005) and OFDM256 (802.16d) are not compatible so most equipment will have to be replaced if an operator wants or needs to move to the later standard. However, some manufacturers are planning to provide a migration path for older equipment to SOFDMA compatibility which would ease the transition for those networks which have already made the OFDM256 investment. This affects a relatively small number users and operators.

WiBro
South Korea's electronics and telecommunication industry spearheaded by Samsung Electronics and ETRI has developed its own standard, WiBro. In late 2004, Intel and LG Electronics have agreed on a merger of mobile WiBro(S-OFDMA modulation) and fixed WiMAX(OFDM modulation) to produce a new standard dubbed Mobile WiMax(802.16e-2005) combining features from both to avoid a future standard war. From this point on WiBro became a specific subset implementation of 802.16e-2005 standard over 8.75 Mhz channels in 2.3 Ghz band, whereas Mobile WiMax represents a full implementation of 802.16e-2005 standard that supports flexible channel size and service band. The side effect of this merger is that Mobile WiMax gears are backward compatible with WiBro gears but not with fixed WiMax gears, reflecting its WiBro originated heritage.

WiBro has South Korean government support with the requirement for each carrier to spend over US$1 billion for deployments. Korea sought to develop WiBro as a regional and potentially international alternative to 3.5G or 4G cellular systems. But given the lack of momentum as a standard, WiBro has joined WiMAX and agreed to harmonize with the similar OFDMA 802.16e version of the standard.

What makes WiBro roll-outs a good "test case" for the overall WiMAX effort is that it is mobile, well thought out for delivery of wireless broadband services, and the fact that the deployment is taking place in a highly sophisticated, broadband-saturated market. WiBro will go up against 3G and very high bandwidth wire-line services rather than as gap-filler or rural under-served market deployments often thought of as "best fit" markets for WiMAX.

As such, WiBRO is now best described as a particular profile within WiMAX with 8.75MHz channel in the 2.3GHz band.

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Wi-Fi

From Wikipedia, the free encyclopedia


Wi-Fi® is a wireless technology brand owned by the Wi-Fi Alliance intended to improve the interoperability of wireless local area network products based on the IEEE 802.11 standards.

Common applications for Wi-Fi® include Internet and VoIP phone access, gaming, and network connectivity for consumer electronics such as televisions, DVD players, and digital cameras.


Uses
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A Wi-Fi enabled device such as a PC, cell phone or PDA can connect to the Internet when within range of a wireless network connected to the Internet. The area covered by one or several interconnected access points is called a hotspot. Hotspots can cover as little as a single room with wireless-opaque walls or as much as many square miles covered by overlapping access points. Wi-Fi can also be used to create a mesh network. Both architectures are used in community networks.

Wi-Fi also allows connectivity in peer-to-peer (wireless ad-hoc network) mode, which enables devices to connect directly with each other. This connectivity mode is useful in consumer electronics and gaming applications.

When the technology was first commercialized there were many problems because consumers could not be sure that products from different vendors would work together. The Wi-Fi Alliance began as a community to solve this issue so as to address the needs of the end user and allow the technology to mature. The Alliance created the branding Wi-Fi CERTIFIED to show consumers that products are interoperable with other products displaying the same branding.

Many consumer devices use Wi-Fi. Amongst others, personal computers can network to each other and connect to the Internet, mobile computers can connect to the Internet from any Wi-Fi hotspot, and digital cameras can transfer images wirelessly.

Routers which incorporate a DSL or cable modem and a Wi-Fi access point are often used in homes and other premises, and provide Internet access and internetworking to all devices connected wirelessly or by cable into them. Devices supporting Wi-Fi can also be connected in ad-hoc mode for client-to-client connections without a router.

Business and industrial Wi-Fi is widespread as of 2007. In business environments, increasing the number of Wi-Fi access points provides redundancy, support for fast roaming and increased overall network capacity by using more channels or creating smaller cells. Wi-Fi enables wireless voice applications (VoWLAN or WVOIP). Over the years, Wi-Fi implementations have moved toward 'thin' access points, with more of the network intelligence housed in a centralized network appliance, relegating individual Access Points to be simply 'dumb' radios. Outdoor applications may utilize true mesh topologies. As of 2007 Wi-Fi installations can provide a secure computer networking gateway, firewall, DHCP server, intrusion detection system, and other functions.

In addition to restricted use in homes and offices, Wi-Fi is publicly available at Wi-Fi hotspots provided either free of charge or to subscribers to various providers. Free hotspots are often provided by businesses such as hotels, restaurants, and airports who offer the service to attract or assist clients. Sometimes free Wi-Fi is provided by enthusiasts, or by organisations or authorities who wish to promote business in their area. Metropolitan-wide WiFi (Mu-Fi) already has more than 300 projects in process.

Advantages of Wi-Fi
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Wi-Fi allows LANs to be deployed without cabling for client devices, typically reducing the costs of network deployment and expansion. Spaces where cables cannot be run, such as outdoor areas and historical buildings, can host wireless LANs.

As of 2007 wireless network adapters are built into most modern laptops. The price of chipsets for Wi-Fi continues to drop, making it an economical networking option included in ever more devices. Wi-Fi has become widespread in corporate infrastructures, which also helps with the deployment of RFID technology that can piggyback on Wi-Fi.

Different competitive brands of access points and client network interfaces are inter-operable at a basic level of service. Products designated as "Wi-Fi Certified" by the Wi-Fi Alliance are backwards inter-operable. Wi-Fi is a global set of standards. Unlike mobile telephones, any standard Wi-Fi device will work anywhere in the world.

Wi-Fi is widely available in more than 250,000 public hotspots and tens of millions of homes and corporate and university campuses worldwide. WPA is not easily cracked if strong passwords are used and WPA2 encryption has no known weaknesses. New protocols for Quality of Service (WMM) make Wi-Fi more suitable for latency-sensitive applications (such as voice and video), and power saving mechanisms (WMM Power Save) improve battery operation.

Disadvantages of Wi-Fi
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Spectrum assignments and operational limitations are not consistent worldwide. Most of Europe allows for an additional 2 channels beyond those permitted in the US (1-13 vs 1-11); Japan has one more on top of that (1-14), and some countries, like Spain, prohibit use of the lower-numbered channels. Europe, as of 2007, is now essentially homogeneous in this respect. Some countries, such as Italy, formerly required a 'general authorization' for any Wi-Fi used outside an operator's own premises, or require something akin to an operator registration.Equivalent isotropically radiated power (EIRP) in the EU is limited to 20 dBm (0.1 W).
Power consumption is fairly high compared to some other low-bandwidth standards, such as Zigbee and Bluetooth, making battery life a concern.

The most common wireless encryption standard, Wired Equivalent Privacy or WEP, has been shown to be easily breakable even when correctly configured. Wi-Fi Protected Access (WPA and WPA2), which began shipping in 2003, aims to solve this problem and is now available on most products. Wi-Fi Access Points typically default to an open (encryption-free) mode. Novice users benefit from a zero-configuration device that works out of the box, but without security enabled, providing open wireless access to their LAN. To turn security on requires the user to configure the device, usually via a software graphical user interface (GUI). Wi-Fi networks that are open (unencrypted) can be monitored and used to read and copy data (including personal information) transmitted over the network, unless another security method is used to secure the data, such as a VPN or a secure web page. (HTTPS/Secure Socket Layer)

Many 2.4 GHz 802.11b and 802.11g Access points default to the same channel on initial startup, contributing to congestion on certain channels. To change the channel of operation for an access point requires the user to configure the device.

Wi-Fi networks have limited range. A typical Wi-Fi home router using 802.11b or 802.11g with a stock antenna might have a range of 45 m (150 ft) indoors and 90 m (300 ft) outdoors. Range also varies with frequency band. Wi-Fi in the 2.4 GHz frequency block has slightly better range than Wi-Fi in the 5 GHz frequency block. Outdoor range with improved (directional) antennas can be several kilometres or more with line-of-sight.

Wi-Fi pollution, or an excessive number of access points in the area, especially on the same or neighboring channel, can prevent access and interfere with the use of other access points by others, caused by overlapping channels in the 802.11g/b spectrum, as well as with decreased signal-to-noise ratio (SNR) between access points. This can be a problem in high-density areas, such as large apartment complexes or office buildings with many Wi-Fi access points. Additionally, other devices use the 2.4 GHz band: microwave ovens, cordless phones, baby monitors, security cameras, and Bluetooth devices can cause significant additional interference.

It is also an issue when municipalities, or other large entities such as universities, seek to provide large area coverage. Everyone is considered equal for the base standard without 802.11e/WMM when they use the band. This openness is also important to the success and widespread use of 2.4 GHz Wi-Fi, but makes it unsuitable for "must-have" public service functions or where reliability is required.

Interoperability issues between brands or proprietary deviations from the standard can disrupt connections or lower throughput speeds on other user's devices that are within range. Additionally, Wi-Fi devices do not, as of 2007, pick channels to avoid interference.

Standard Devices
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Wireless access points connects a group of wireless devices to an adjacent wired LAN. An access point is similar to an ethernet hub, relaying data between connected wireless devices in addition to a (usually) single connected wired device, most often an ethernet hub or switch, allowing wireless devices to communicate with other wired devices.

Wireless adapters allow devices to connect to a wireless network. These adapters connect to devices using various external or internal interconnects such as PCI, miniPCI, USB, ExpressCard, Cardbus and PC card. Most newer laptop computers are equipped with internal adapters. Internal cards are generally more difficult to install.

Wireless routers integrate WAP, ethernet switch, and internal Router firmware application that provides IP Routing, NAT, and DNS forwarding through an integrated WAN interface. A wireless router allows wired and wireless ethernet LAN devices to connect to a (usually) single WAN device such as cable modem or DSL modem. A wireless router allows all three devices (mainly the access point and router) to be configured through one central utility. This utility is most usually an integrated web server which serves web pages to wired and wireless LAN clients and often optionally to WAN clients. This utility may also be an application that is run on a desktop computer such as Apple's AirPort.

Wireless Ethernet bridges connect a wired network to a wireless network. This is different from an access point in the sense that an access point connects wireless devices to a wired network at the data-link layer. Two wireless bridges may be used to connect two wired networks over a wireless link, useful in situations where a wired connection may be unavailable, such as between two separate homes.

Wireless range extenders or wireless repeaters can extend the range of an existing wireless network. Range extenders can be strategically placed to elongate a signal area or allow for the signal area to reach around barriers such as those created in L-shaped corridors. Wireless devices connected through repeaters will suffer from an increased latency for each hop. Additionally, a wireless device at the end of chain of wireless repeaters will have a throughput that is limited by the weakest link within the repeater chain.

Most commercial devices (routers, access points, bridges, repeaters) designed for home or business environments use either RP-SMA or RP-TNC antenna connectors. PCI wireless adapters also mainly use RP-SMA connectors. Most PC card and USB wireless only have internal antennas etched on their printed circuit board while some have MMCX connector or MC-Card external connections in addition to an internal antenna. A few USB cards have a RP-SMA connector. Most Mini PCI wireless cards utilize Hirose U.FL connectors, but cards found in various wireless appliances contain all of the connectors listed. Many high-gain (and homebuilt antennas) utilize the Type N connector more commonly used by other radio communications methods.

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