1-4 Media and Topologies

1.4 Recognize the following media connectors and describe their uses:

> RJ-11 (Registered Jack)

Standard telephone cable connectors, RJ-11 has 4 wires (and RJ-12 has 6 wires).

Pinout of the 1-Wire plug that connects to the socket on a TINI E20 Revision C board, or a 9097U adapter.	RJ-11 Pin	Signal Name
	1	VCC (5 volts regulated)
	2	Power Ground
	3	One Wire Data
	4	One Wire Ground
	5	No Connect
	6	V+ (unregulated DC)

> RJ-45 (Registered Jack)

RJ-45 The "RJ" stands for Registered Jack. These connectors are used with 10-100BaseT cables, and resemble telephone RJ-11 connectors, but are larger. They are connected to the cable by crimping.

Used for Ethernet cable connectors, where usually 8 pins (4 pairs) are used, e.g., a male-to-male cable to connect a cable or ADSL modem to the computer Ethernet network card. Applications include other networking services such as ISDN and T1.

RJ-45 Wiring (EIA/TIA-568B)

Pin	Pair	Wire	Color	Pins
1	2	1	white/orange
2	2	2	orange
3	3	1	white/green
4	1	2	blue
5	1	1	white/blue
6	3	2	green
7	4	1	white/brown
8	4	2	brown

> F-Type

The F connector is a type of RF connector commonly used for cable and universally for satellite television. They are also used for the cable TV connection in DOCSIS cable modems, usually with RG-6 tri-shield cable. The F connector is inexpensive, yet has good performance up to 1 GHz. One reason for its low cost is that it uses the center wire of the coaxial cable as the pin of the male connector. The male connector body is typically crimped onto the exposed outer braid. Female connectors have a 3/8-32 thread. Most male connectors have a matching threaded connecting ring, though push-on versions are also available.

> ST (Straight Tip) and SC (Subscriber Connector or Standard Connector)

Fiber network segments always require two fiber cables: one for transmitting data, and one for receiving. Each end of a fiber cable is fitted with a plug that can be inserted into a network adapter, hub, or switch. In the North America, most cables use a square SC connector (Subscriber Connector or Standard Connector) that slides and locks into place when inserted into a node or connected to another fiber cable, Europeans use a round ST connector (Straight Tip) instead.

SC connector (Subscriber Connector or Standard Connector)

ST connector (Straight Tip)

Both connectors offer the same features as far as distance and reliability, Connectors of different types can communicate with the use of adapters or couplers, but it is best to choose one type of connector and stick with it over your entire network.

> IEEE 1394 (FireWire)

Is a personal computer (and digital audio/video) serial bus interface standard, offering high-speed communications and isochronous real-time data services. FireWire can be considered a successor technology to the obsolescent SCSI Parallel Interface. Up to 63 devices can be daisy-chained to one FireWire port.

IEEE 1394 connectors are used to connect FireWire devices such as host controllers, adapters, hard drives, hubs, repeaters, and card readers. FireWire, a registered trademark of Apple Computer, is a communications protocol for the transmission of data, video, and audio over a single cable at very high bit rates. IEEE 1394 is an interface standard adopted by the Institute of Electrical and Electronics Engineers (IEEE) for digital data transfers at 400 Mbps. The popularity of IEEE 1394 is due in part to its use of a bus-powered architecture that does not require peripherals to supply their own power. Products that support the IEEE 1394 standard adhere to its specifications, but often use proprietary trade names. For example, Sony uses the term iLink to describe its FireWire products. iLink is a registered trademark of the Sony Corporation.

There are two basic types of IEEE 1394 connectors: four-pin and six-pin. Four-pin or four-position FireWire connectors are used with digital video camcorders and other devices that have a small footprint and do not require external power. By contrast, six-pin or six-position connectors are used with personal computers (PCs), rewritable compact disc rewritable drives (CDRWs), external hard drives, digital audio stations, and other larger, more durable FireWire devices that use external power. Four-pin connectors are rectangular, 1/4” by 1/8” devices in which one of the longer sides is indented. Six-pin connectors are rectangular, 1/2” by 3/16” devices in which one of the smaller sides is rounded. Four-pin and six-pin IEEE 1394 connectors are either straight or right-angled.

> Fiber LC (Local Connector)

These connectors are used for single-mode and multimode fiber-optic cables. FC connectors offer extremely precise positioning of the fiber-optic cable with respect to the transmitter's optical source emitter and the receiver's optical detector. FC connectors feature a position locatable notch and a threaded receptacle.

> MT-RJ (Mechanical Transfer Registered Jack)

MT-RJ connectors are used with single-mode and multimode fiber-optic cables. The MT-RJ connectors are constructed with a plastic housing and provide for accurate alignment via their metal guide pins and plastic ferrules.

Used for Gigabit ethernet. To connect to modules with MT-RJ interfaces, use multimode fiber-optic cables.

> USB (Universal Serial Bus)

Universal Serial Bus, or USB, is a computer standard designed to eliminate the guesswork in connecting peripherals to a PC. It is expected to replace serial and parallel ports. A single USB port can be used to connect up to 127 peripheral devices, such as mice, modems, keyboards, digital camera's, printers, scanners, MP3 players and many more. USB also supports Plug-and-Play installation and hot plugging.

• USB 1.1 standard supports data transfer rates of 12 Mbps.
• USB 2.0 (Also referred to as Hi-Speed USB) specification defines a new High-speed transfer rate of 480 Mb/sec.

USB 2.0 is fully compatible with USB 1.1 and uses the same cables and connectors.

USB has with two connector types. The first is Type A (on the right), This connector connects to the PC's USB port.

The Type B (on the left) connector and is for connecting to the relevant peripheral.

Where as the type A connector is truly standard, the Type B connector could be changed in size etc. with individual peripherals meaning they require there own unique cables.

> Coaxial Connectors

BNC connector for coaxial cables. These are either soldered, or crimped to the end of the cable.

BNC T connector, which joins the network card to the network cable.

BNC barrel connector, used to connect two cables together. It is better to use one continuous length of cable, as these connectors weaken the signal strength.

A thicknet network connection uses a 15 pin attachment unit interface (AUI) to connect the 15 pin DB 15 connector on the back of the network adapter card to an external transceiver (shown left). The transceiver for thicknet Ethernet includes a vampire tap (shown on top of the transceiver) which pierces the thicknet cable to make the network connection. From the transceiver to the network card a drop cable is attached.