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Wi-Fi, also spelled Wifi or WiFi, is a technology that allows an electronic device to exchange data or connect to the internet wirelessly using 2.4 GHz UHF and 5 GHz SHF radio waves. The name is a trademark name, and was stated to be a play on the audiophile term Hi-Fi. The Wi-Fi Alliance defines Wi-Fi as any "wireless local area network (WLAN) products that are based on the Institute of Electrical and Electronics Engineers' (IEEE) 802.11 standards".[1] However, since most modern WLANs are based on these standards, the term "Wi-Fi" is used in general English as a synonym for "WLAN". Only Wi-Fi products that complete Wi-Fi Alliance interoperability certification testing successfully may use the "Wi-Fi CERTIFIED" trademark. Depiction of a device sending information wirelessly to another device, both connected to the local network, in order to print a document. Wi-Fi can be less secure than wired connections (such as Ethernet) because an intruder does not need a physical connection.

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LG Optimus Black The LG P970 Optimus Black is a smartphone designed and manufactured by LG Electronics and was released in 2011. At 9.2 mm in thickness, it was LG's thinnest smartphone at the time of its release, and is slightly thinner than the iPhone 4. The LG Optimus Black features a WVGA NOVA display which is brighter than competitor displays with brightness officially claimed to be over 700 nits. However, the actual brightness of the screen is measured to be about 749 nits.[4] Furthermore, the NOVA display consumes less energy compared to competitor displays.[5] LG Optimus Black is claimed to be the first smartphone with 2MP front camera.

Firewall (computing) An illustration of where a firewall would be located in a network. In computing, a firewall is a software or hardware-based network security system that controls the incoming and outgoing network traffic by analyzing the data packets and determining whether they should be allowed through or not, based on applied rule set. A firewall establishes a barrier between a trusted, secure internal network and another network (e.g., the Internet) that is not assumed to be secure and trusted.[1] Firewall technology emerged in the late 1980s when the Internet was a fairly new technology in terms of its global use and connectivity. The predecessors to firewalls for network security were the routers used in the late 1980s:[3] The first paper published on firewall technology was in 1988, when engineers from Digital Equipment Corporation (DEC) developed filter systems known as packet filter firewalls.

Wi-Fi Range - Which Wireless Router Has the Best Wi-Fi Signal? Question: Which Wireless Router Offers the Best WiFi Range? Consumer wireless routers vary in the Wi-Fi range they support. Routers with stronger Wi-Fi signals allow devices to connect at higher speeds from a greater distance and stay connected more reliably. Which wireless router then, has the overall best Wi-Fi range? Answer: A wireless router's antenna technology generally determines its Wi-Fi signal strength and hence its range. Generally speaking, 802.11g wireless routers offer better Wi-Fi range than comparable 802.11b units due to improved antennas.

RS-232 A DB-25 connector as described in the RS-232 standard In telecommunications, RS-232 is a standard for serial communication transmission of data. It formally defined the signals connecting between a DTE (data terminal equipment) such as a computer terminal, and a DCE (data circuit-terminating equipment, originally defined as data communication equipment[1]), such as a modem. The RS-232 standard is commonly used in computer serial ports. The standard defines the electrical characteristics and timing of signals, the meaning of signals, and the physical size and pinout of connectors. The current version of the standard is TIA-232-F Interface Between Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange, issued in 1997.

IEEE 802.11n-2009 IEEE 802.11n-2009, commonly shortened to 802.11n, is a wireless networking standard that uses multiple antennas to increase data rates. It is an amendment to the IEEE 802.11-2007 wireless networking standard. Its purpose is to improve network throughput over the two previous standards—802.11a and 802.11g—with a significant increase in the maximum net data rate from 54 Mbit/s to 600 Mbit/s (slightly higher gross bit rate including for example error-correction codes, and slightly lower maximum throughput) with the use of four spatial streams at a channel width of 40 MHz.[1][2] 802.11n standardized support for multiple-input multiple-output and frame aggregation, and security improvements, among other features. It can be used in the 2.4 GHz or 5 GHz frequency bands. 802.11 is a set of IEEE standards that govern wireless networking transmission methods. Description[edit]

Proxy server Communication between two computers (shown in grey) connected through a third computer (shown in red) acting as a proxy. Note that Bob doesn't know whom the information is going to, which is why proxies can be used to protect privacy. Types of proxy[edit] RS-485 TIA-485-A, also known as ANSI/TIA/EIA-485, TIA/EIA-485, EIA-485 or RS-485, is a standard defining the electrical characteristics of drivers and receivers for use in balanced digital multipoint systems. The standard is published by the Telecommunications Industry Association/Electronic Industries Alliance (TIA/EIA). Digital communications networks implementing the EIA-485 standard can be used effectively over long distances and in electrically noisy environments. Multiple receivers may be connected to such a network in a linear, multi-drop configuration.

Arduino Arduino is an open-source computer hardware and software company, project and user community that designs and manufactures kits for building digital devices and interactive objects that can sense and control the physical world.[1] Arduino boards may be purchased preassembled, or as do-it-yourself kits; at the same time, the hardware design information is available for those who would like to assemble an Arduino from scratch. The first Arduino was introduced in 2005. The project leaders sought to provide an inexpensive and easy way for hobbyists, students, and professionals to create devices that interact with their environment using sensors and actuators. Common examples for beginner hobbyists include simple robots, thermostats and motion detectors. Adafruit Industries estimated in mid-2011 that over 300,000 official Arduinos had been commercially produced,[3] and in 2013 that 700,000 official boards were in users' hands.[4] History[edit]

IEEE 802.11 IEEE 802.11 is a set of media access control (MAC) and physical layer (PHY) specifications for implementing wireless local area network (WLAN) computer communication in the 2.4, 3.6, 5 and 60 GHz frequency bands. They are created and maintained by the IEEE LAN/MAN Standards Committee (IEEE 802). The base version of the standard was released in 1997 and has had subsequent amendments. What Is The Difference Between Cat 5, Cat 5e, and Cat 6 Cable? So, let's say you want to play one of those new-fangled gaming console devices I've heard so much about, or you just want to connect to that that all the hip youngsters can't stop gabbing about. Well, you'll need some type of cable, right? (Spoiler alert: Right.) In your magical Quest to Find the Right Cable (soon to be a trilogy directed by Peter Jackson), you'll likely come across Cat 5, Cat 5e, and Cat 6 cables with no clue as to what these designations mean.

Tech Know: CHoosing an e-reader Technology continues to advance day after day to become one of the most important aspects of a person's life. Get tips on tech and learn about choosing better equipment from eHow's Tech Know. Choosing an E-Book Reader Primary Rate Interface The Primary Rate Interface (PRI) is a standardized telecommunications service level within the Integrated Services Digital Network (ISDN) specification for carrying multiple DS0 voice and data transmissions between a network and a user. PRI is the standard for providing telecommunication services to offices. It is based on the T-carrier (T1) line in the US and Canada, and the E-carrier (E1) line in Europe.