The document discusses various network media and hardware components. It describes transmission media like twisted pair cable, coaxial cable, and optical fiber cable. It also discusses network interface cards, connectors like RJ-45 and fiber optic connectors, and network devices like repeaters, hubs, switches, and routers.

1. Unit – III Network Media and Hardware
3.1 Transmission Media: Unguided and Guided media, Wired
and Wireless, UTP, Coaxial and Fiber optical cable
3.2 Types of Connectors: RJ-45, RJ-11, BNC, BNC –T, BNC
Terminator, Fiber optic connectors:- Subscriber Channel(SC),
Straight Tip(ST), Mechanical transfer – registered jack(MT-RJ)Straight Tip(ST), Mechanical transfer – registered jack(MT-RJ)
connectors
3.3 Network Interface Card (NIC), ARCNET, Ethernet.
3.4 Network connecting devices: Repeater, Hub, Bridge,
Switch , Router, Gateway, Access point, Wireless Access points

2. (i) Twisted Pair Cable –
It consists of 2 separately insulated conductor wires wound about each other. Generally,
several such pairs are bundled together in a protective sheath. They are the most widely
used Transmission Media. Twisted Pair is of two types:
Unshielded Twisted Pair (UTP):
This type of cable has the ability to block interference and does not depend on a physical
shield for this purpose. It is used for telephonic applications. Advantages:
Least expensive
Easy to install
High speed capacity
Disadvantages:
Susceptible to external interferenceSusceptible to external interference
Lower capacity and performance in comparison to STP
Short distance transmission due to attenuation
Shielded Twisted Pair (STP):
This type of cable consists of a special jacket to block external interference. It is used in fast-
data-rate Ethernet and in voice and data channels of telephone lines. Advantages:
Better performance at a higher data rate in comparison to UTP
Eliminates crosstalk
Comparatively faster
Disadvantages:
Comparatively difficult to install and manufacture
More expensive
Bulky

3. (ii)CoaxialCable –
It has an outer plastic covering containing 2 parallel conductors each having a separate insulated
protection cover. Coaxial cable transmits information in two modes: Baseband mode(dedicated
cable bandwidth) and Broadband mode(cable bandwidth is split into separate ranges). Cable TVs
and analog television networks widely use Coaxial cables.
Advantages:
High Bandwidth
Better noise Immunity
Easy to install and expand
Inexpensive
Disadvantages:
Single cable failure can disrupt the entire network
(iii)OpticalFibreCable –
It uses the concept of reflection of light through a core made up of glass or plastic. The core is
surrounded by a less dense glass or plastic covering called the cladding. It is used for
transmission of large volumes of data.
Advantages:
Increased capacity and bandwidth, Light weight,Less signal attenuation
Disadvantages:
Difficult to install and maintain
High cost
Fragile

4. 2. Unguided Media:
It is also referred to as Wireless or Unbounded transmission media.No physical medium is
required for the transmission of electromagnetic signals.
Features:
Signal is broadcasted through air
Less Secure
Used for larger distances
There are 3 major types of Unguided Media:
(i) Radio waves –
These are easy to generate and can penetrate through buildings. The sending and receiving
antennas need not be aligned. Frequency Range:3KHz – 1GHz. AM and FM radios andantennas need not be aligned. Frequency Range:3KHz – 1GHz. AM and FM radios and
cordless phones use Radio waves for transmission.
Further Categorized as: (i) Terrestrial and (ii) Satellite.
(ii) Microwaves –
It is a line of sight transmission i.e. the sending and receiving antennas need to be properly
aligned with each other. The distance covered by the signal is directly proportional to the
height of the antenna. Frequency Range:1GHz – 300GHz. These are majorly used for mobile
phone communication and television distribution.
(iii) Infrared –
Infrared waves are used for very short distance communication. They cannot penetrate
through obstacles. This prevents interference between systems. Frequency Range:300GHz
– 400THz. It is used in TV remotes, wireless mouse, keyboard, printer, etc

5. 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 USBtwo 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.

6. RJ-11 (Registered Jack)
Standard telephone cable connectors, RJ-11 has 4 wires (and RJ-12 has 6 wires). RJ-11 is
the acronym for Registered Jack-11, a four- or six-wire connector primarily used to
connect telephone equipment.
RJ-11 PinSignal Name1VCC (5 volts regulated)2Power Ground3One Wire Data4One Wire
Ground
RJ-11 Pin Signal Name
1 VCC (5 volts regulated)
2 Power Ground
3 One Wire Data
4 One Wire Ground

7. RJ-45 (Registered Jack)
The acronym for Registered Jack-45 is RJ-45. The RJ-45 connector is an eight-wire connector
that is commonly used to connect computers to a local area network (LAN), particularly
Ethernet LANs. Although they are slightly larger than the more commonly used RJ-
11 connectors, RJ-45s can be used to connect some types of telephone equipment.
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.connecting ring, though push-on versions are also available.

8. 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
ST connector
Fiber LC (Local Connector)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-RJinterfaces, use multimode
fiber-optic cables.

9. SC & ST connectors

11. •A NIC (Network Interface Card) provides the hardware interface between a computer and a
network. These days, almost all new computer motherboards have in-built NIC (Network
Interface Card).
•Some NIC (Network Interface Card) cards are meant for wired networks while others are for
wireless network. Most widely used wired LAN Technology is Ethernet. Ethernet based NIC
(Network Interface Card) cards are available in every local electronic hardware shops. Normal
speed rating of Ethernet based wired NIC (Network Interface Card) available these days are
10/100/1000 Mbps (Mega bits per second).
•Every computer participating in network must have at least one NIC. Computers can have
more than one NIC card also, if required.
•Every NIC (Network Interface Card) has a 48-bit globally unique identifier called as MAC
Address (Media Access Control Address) burned into its ROM chip. This MAC address is used
to deliver Ethernet Frames (packets) to a computer.to deliver Ethernet Frames (packets) to a computer.
•The NIC driver software passes the data between the Operating System and the NIC. Latest
Operating Systems include different NIC driver software for almost all major NIC vendors. If
your NIC card is not detected or not working, you must find a suitable NIC driver software
from the NIC vendor's website and install it on the computer.

13. •Attached Resource Computer Network (ARCnet) is a type of LAN protocol that provides
network services to 255 nodes at data rates of up to 2.5 Mbps. ARCnet is similar to token ring
and Ethernet network services.
ARCnet was fast, reliable and cheap, and it allowed different transmission systems to be merged
and implemented on same network. ARCnet was the first simple networking based solution that
provided for all kinds of transmission regardless of the transmission medium or the type of
computer. ARCnet was also the first widely available networking system for microcomputers.
Although a new ARCnet specification, ARCnet Plus, has been developed to deliver data transfer
rates of 20 Mbps, ARCnet is still used in the embedded systems market.

14. •An Ethernet card is one kind of network adapter. These adapters support the Ethernet
standard for high-speed network connections using cable connections.
•Although they used to be ubiquitous, wired Ethernet ports are gradually being
supplanted in computers by Wi-Fi networking capability, which offers adequate speed
relative to Ethernet but without the cost of a large port or the hassle of running a cable
from an Ethernet jack to a PC.
•Ethernet cards are part of a category of computing hardware called network interface
cards

15. Repeaters • The number of nodes on a network and the length of cable used – Influence the
quality of communication on the network • Attenuation – The degradation of signal clarity •
Repeaters – Work against attenuation by repeating signals that they receive on a network •
Typically cleaning and regenerating the digital transmission in the process

24. Reference:
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