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1. OSI Physical Layer

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Data over Tellephone Lines

Serial Networks. Optical Transport Network. Ethernet Over Twisted Pair. IEEE 802.3 (Ethernet layer 1&2, MAC of wired Ethernet) Wireless Communication. Wi-fi. IEEE 802.11 ((MAC) and (PHY) spec for WLAN) Bluetooth. IEEE 1394. IEEE 1394 is the High-Definition Audio-Video Network Alliance (HANA) standard connection interface for A/V (audio/visual) component communication and control.[3] FireWire is also available in wireless, fiber optic, and coaxial versions using the isochronous protocols. History and development[edit] The 6-conductor and 4-conductor alpha FireWire 400 connectors A 9-pin FireWire 800 connector 4-conductor (left) and 6-conductor (right) FireWire 400 alpha connectors A pair of 6-conductor alpha connectors on the edge of an expansion card FireWire is Apple's name for the IEEE 1394 High Speed Serial Bus.

It was initiated by Apple (in 1986[4]) and developed by the IEEE P1394 Working Group, largely driven by contributions from Apple, although major contributions were also made by engineers from Texas Instruments, Sony, Digital Equipment Corporation, IBM, and INMOS/SGS Thomson (now STMicroelectronics). Intellectual property considerations[edit] Technical specifications[edit] Encoding scheme[edit] IEEE 802.16.

IEEE 802.16 is a series of wireless broadband standards written by the Institute of Electrical and Electronics Engineers (IEEE). The IEEE Standards Board established a working group in 1999 to develop standards for broadband for wireless metropolitan area networks. The Workgroup is a unit of the IEEE 802 local area network and metropolitan area network standards committee. Although the 802.16 family of standards is officially called WirelessMAN in IEEE, it has been commercialized under the name "WiMAX" (from "Worldwide Interoperability for Microwave Access") by the WiMAX Forum industry alliance.

The Forum promotes and certifies compatibility and interoperability of products based on the IEEE 802.16 standards. The 802.16e-2005 amendment version was announced as being deployed around the world in 2009.[1] The version IEEE 802.16-2009 was amended by IEEE 802.16j-2009. Standards[edit] Projects[edit] 802.16e-2005 Technology[edit] PHY[edit] MAC[edit] QoS[edit] Certification[edit] See also[edit] IEEE 802.15. IEEE 802.15 is a working group of the Institute of Electrical and Electronics Engineers (IEEE) IEEE 802 standards committee which specifies wireless personal area network (WPAN) standards. It includes seven task groups. Task Group 1: WPAN / Bluetooth[edit] Task group one is based on Bluetooth technology. It defines physical layer (PHY) and Media Access Control (MAC) specification for wireless connectivity with fixed, portable and moving devices within or entering personal operating space.

Standards were issued in 2002 and 2005.[1][2] Task Group 2: Coexistence[edit] Task group two addresses the coexistence of wireless personal area networks (WPAN) with other wireless devices operating in unlicensed frequency bands such as wireless local area networks (WLAN). Task Group 3: High Rate WPAN[edit] IEEE 802.15.3-2003 is a MAC and PHY standard for high-rate (11 to 55 Mbit/s) WPANs. IEEE 802.15.3b-2005 amendment was released on May 5, 2006. IEEE 802.15.3c-2009 was published on September 11, 2009. IEEE 802.3. 802.3 is a technology that supports the IEEE 802.1 network architecture. 802.3 also defines LAN access method using CSMA/CD Communication Standards[edit] See also[edit] References[edit] Ethernet: IEEE 802.3 Local Area Network (LAN) protocols External links[edit] Digital subscriber line. Digital subscriber line (DSL; originally digital subscriber loop) is a family of technologies that provide internet access by transmitting digital data using a local telephone network which uses the Public switched telephone network.

In telecommunications marketing, the term DSL is widely understood to mean asymmetric digital subscriber line (ADSL), the most commonly installed DSL technology. DSL service is delivered simultaneously with wired telephone service on the same telephone line. This is possible because DSL uses higher frequency bands for data. On the customer premises, a DSL filter on each non-DSL outlet blocks any high frequency interference, to enable simultaneous use of the voice and DSL services. A 2007 book described DSL as "the most globally prolific broadband access technology, yet it is only available to around 60–75 percent of the population in many developed countries.

History[edit] A DSL circuit provides digital service. Operation[edit] Basic technology[edit] Joseph W. G.hn. G.hn is the common name for a home network technology family of standards developed under the International Telecommunication Union's Telecommunication Standardization sector (the ITU-T) and promoted by the HomeGrid Forum[1] and several other organizations.[2] The G.hn specifications define networking over power lines, phone lines and coaxial cables with data rates up to 1 Gbit/s.[3] ITU-T Recommendation (the ITU's term for standard) G.9960, which received approval on October 9, 2009,[4] specified the physical layers and the architecture of G.hn.

The Data Link Layer (Recommendation G.9961) was approved on June 11, 2010.[5] The work was done in the ITU Telecommunication Standardization Sector, Study Group 15, Question 4. About 20 companies participated in the work, including telephone, communication equipment, and home networking technology companies. Unified communication[edit] G.hn is a specification for existing-wire home networking. It is a complementary counterpart to Wi-Fi. Plesiochronous digital hierarchy. The plesiochronous digital hierarchy (PDH) is a technology used in telecommunications networks to transport large quantities of data over digital transport equipment such as fibre optic and microwave radio systems.[1] The term plesiochronous is derived from Greek plēsios, meaning near, and chronos, time, and refers to the fact that PDH networks run in a state where different parts of the network are nearly, but not quite perfectly, synchronised. PDH is typically[when?] Being replaced by synchronous digital hierarchy (SDH) or synchronous optical networking (SONET) equipment in most telecommunications networks.

PDH allows transmission of data streams that are nominally running at the same rate, but allowing some variation on the speed around a nominal rate. By analogy, any two watches are nominally running at the same rate, clocking up 60 seconds every minute. Implementation[edit] The data rate is controlled by a clock in the equipment generating the data. See also[edit] References[edit] I.430. I.431. The I.431/430 Networking standards are recommendations produced by the ITU. They are Layer 1 specifications for ISDN networks, using either an E1 or T1 circuit. The I.431 standard is known as the 'PRI Physical Layer' whereas the I.430 is known as the 'BRI Physical Layer'. I.431 : Primary rate user-network interface - Layer 1 specification from the ITU. USB. Overview[edit] In general, there are four basic kinds or sizes related to the USB connectors and types of established connections: the older "standard" size, in its USB 1.1/2.0 and USB 3.0 variants (for example, on USB flash drives)the "mini" size (primarily for the B connector end, such as on many cameras)the "micro" size, in its USB 1.1/2.0 and USB 3.0 variants (for example, on most modern cellphones)the versatile "USB On-The-Go" scheme, in both mini and micro sizes.

Unlike other data cables (Ethernet, HDMI etc.), each end of a USB cable uses a different kind of connector; an A-type or a B-type. This kind of design was chosen to prevent electrical overloads and damaged equipment, as only the A-type socket provides power. Counter-intuitively, the "micro" size is the most durable from the point of designed insertion lifetime, as the result of latching mechanism (parts providing gripping force) being moved into plugs on the cable side.[5] History[edit] The basic USB trident logo[6] List of ITU-T V-series recommendations. The ITU-T V-Series Recommendations on Data communication over the telephone network specify the protocols that govern approved modem communication standards and interfaces.[1] Note: the bis and ter suffixes are ITU-T standard designators of successive iterations of a standard (bis and ter are derived from the Latin for "twice" and "thrice"). General standards[edit] Applies to V.1–V.9 Interfaces and voiceband modems[edit] Applies to V.10–V.34 Ad hoc standards[edit] In order to gain first-mover advantage, many modem companies introduced models based on upcoming V-series standards before they reached final ratification.

V.32terbo, or V.32ter for short, was a 19.2 kbit/s standard introduced by AT&T Paradyne. Wideband modems[edit] Applies to V.35–V.39 V.35 is an ITU-T standard located on layer 1 on the OSI model. Error control and data compression[edit] Applies to V.40–V.49 V.41 is a code-independent error control system. Simultaneous transmission of data and other signals[edit] Applies to V.60–V.99. 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. Scope of the standard[edit] The Electronic Industries Association (EIA) standard RS-232-C[1] as of 1969 defines: History[edit] Limitations of the standard[edit] Role in modern personal computers[edit] Standard details[edit]

RS-449. The RS-449 specification, also known as EIA-449 or TIA-449, defines the functional and mechanical characteristics of the interface between data terminal equipment and data communications equipment. The electrical signaling standards intended for use with RS-449 are RS-422 for balanced signals, and RS-423 for the unbalanced signals, with data rates to 2 Mbit/s. The standard specifies DC-37 and DE-9 for the primary and secondary data circuits. Though never applied on personal computers, this interface is found on some network communication equipment.

The full title of the standard is EIA-449 General Purpose 37-Position and 9-Position Interface for Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange. EIA-449-1 was rescinded in January, 1986. Notes[edit] Jump up ^ "TIA Standards Documents". References[edit] External links[edit]

RS-449. RS-232. 1 & 2. IPS Link Layer (Internet Protocol Suite) Synchronous optical networking. SONET and SDH, which are essentially the same, were originally designed to transport circuit mode communications (e.g., DS1, DS3) from a variety of different sources, but they were primarily designed to support real-time, uncompressed, circuit-switched voice encoded in PCM format.[3] The primary difficulty in doing this prior to SONET/SDH was that the synchronization sources of these various circuits were different. This meant that each circuit was actually operating at a slightly different rate and with different phase. SONET/SDH allowed for the simultaneous transport of many different circuits of differing origin within a single framing protocol.

SONET/SDH is not itself a communications protocol per se, but a transport protocol. Due to SONET/SDH's essential protocol neutrality and transport-oriented features, SONET/SDH was the obvious choice for transporting the fixed length Asynchronous Transfer Mode (ATM) frames also known as cells. Difference from PDH[edit] Protocol overview[edit]