MY ASSIGNMENT

1.What is Network Topology?

Network topology is the physical interconnections of the elements (links, nodes, etc.) of a computer network

Defines the way in which computers, printers, and other devices are connected, physically and logically. A network topology describes the layout of the wire and devices as well as the paths used by data transmissions.

2.Examples of Network Topology, their Definition and Post Example Picture.

• Star topology

Also known as a star network, a star topology is one of the most common network setups where each of the devices and computers on a network connect to a central hub. A major disadvantage of this type of network topology is that if the central hub fails, all computers connected to that hub would be disconnected. Below is a visual example of a simple computer setup on a network using the star topology.

• Ring topology

Also known as a ring network, the ring topology is a type of computer network configuration where each network comput er and device are connected to each other forming a large circle (or similar shape). Each packet is sent around the ring until it reaches its final destination. Today, the ring topology is seldom used. Below is a visual example of a simple computer setup on a network using a ring topology.

• Mesh Topology

Mesh Network is a network where all the nodes are connected to each other and is a complete network. In a Mesh Network every node is connected to other nodes on the network through hops. Some are connected through single hops and some may be connected with more than one hope.

• Tree topology

Also known as a star bus topology, tree topology is one of the most common types of network setups that is similar to a bus topology and a star topology. A tree topology connects multiple star networks to other star networks. Below is a visual example of a simple computer setup on a network using the star topology

3. What is OSI Layer?

OSI - Open Systems Interconnection

4. Example of OSI Layer,Their Definition in Oder.

Short for Open System Interconnection, OSI is a network model developed by ISO in 1978 where peer-to-peer communications are divided into seven layers. Each layer performs a specific task or tasks, and builds upon the preceding layer until the communications are complete. Below are the purposesof each of the seven layers.

1 - Physical layer - responsible for the electrical, mechanical and timing across the link.

2 - Data link layer (also knownas the link layer) - responsible for t
ransmitting data across a link.

3 - Network layer - responsible for routing information through the network and allowing systems to communicate.

4 - Transport layer - responsible for transferring information between endpoints on the network and deals with errors such as lost or duplicate packets.

5 - Session layer - responsible for managing a session between two applications.

6 - Presentation layer - responsible for the data formatting and display, allowing for compatibility.

7 - Application layer - responsible for user interaction. An example of an OSI application is the FTAM.· Short for Open-Source Initiative, OSI is a non-profit corporation dedicated to managing and promoting Open Source.

5. What is Networking?

Computer networking is the engineering discipline concerned with communication between computer systems or devices. Networking, routers, routing protocols, and networking over the public Internet have their specifications defined in documents called RFCs.^[1] Computer networking is sometimes considered a sub-discipline of telecommunications, computer science, information technology and/or computer engineering. Computer networks rely heavily upon the theoretical and practical applicatio n of th ese scientific and engineering disciplines

6. Example of Networking,Post at least 5 examples with pictures.

• LAN - Local Area Network
  

Local Area Network " which offer small businesses / univerties computer networks for employees and students. A LAN doesn't have to be connected to the Internet, but the majority do offer Internet facili ties. LAN can run a wide range of network operating systems such as Windows NT, Unix and Novell Netware.

• MAN - Metropolitan Area Network
  

Metropolitan area network (MAN) is a large computer network that usually spans a city or a large campus. A MAN usually interconnects a number of local area networks (LANs) using a high-capacity backbone technology, su ch as fiber-optical links, and provides up-link services to wide area networks and the Inter

net.

• WAN - Wide Area Network

Wide area network (WAN) is a com puter network that covers a broad area (i.e., any network whose communicatio ns links cross metropolitan, regional, or national boundaries ^[1]). This is in contrast with personal area networks (PANs), local area networks (LANs), campus area networks (CANs), or metropolitan area networks (MANs) which are usually limited to a room, building, campus or specific metropolitan area respectively.

• CAN - Controller Area Network

CAN is the leading serial bus system for embedded control. More than two billion CAN nodes have been sold since the protocol's development in the early 1980s. CAN is a mainstream network and was internationally standardized (ISO 11898–1) in 1993.

• PAN - Personal Area Network
  

Personal area network (PAN ) is a computer network used for communication among computer devices (including telephones and personal digital assistants) close to one's person. The devices may or may not belong t o the person in question. The reach of a PAN is typically a few meters. PANs can be used for communication

among the personal devices themselves (intrapers onal communication), or for connecting to a higher level network and the Internet (an uplink).

7. Example of Networking Devices and Their Functions, Post at least 10 w/ picture.

• Router

A hardware device designed to take incoming packets, analyzing the packets and then directing them to the appropriate

locations, moving the packets to another network, converting the packets to be moved across a different type of network interface, dropping the packets, or performing any other number of other types of actions. To the right is a picture of the Linksys BEFSR11 router and is similar to what most home users would use for their home network.

• Hub

1. When referring to a network, a hub is a basic networking device that connects multiple computers and/or other network devices together.

1. In general, a
   hub refers to a hardware device that enables multiple devic es or connections to be connected to a computer. Another example besides the one given above is a USB hub, which allows dozens of USB devices to be connected to one computer, even though that computer may only have a few USB connections. Below is an examp le picture
   of a USB hub.

• GBIC

Short for Gigabit Interface Converter, GBIC is a hot-swappable networking component that enables a router, switch, or

other network device to have support for different types of connections. For example, a network router may have a blade that supports several different types of GBICs, meaning the user can use different types of fiber connections, copper connections, or other types of network connections. Below is a graphic illustration of a single 10000BASE-SX NETGEAR GBIC module.

• Switch

A piece of a physical circuitry component that governs signal flow. Having the switch open allows the signal to flow through, while keeping the switch closed stops the flow and breaks the circuit connection.

• Network Interface Card

A network interface card is used to connect a computer to an Ethernet network. The card (shown in the figure below) provides an interface tothe media. This may be either using an external transceiver (as shown) or through an internal integrated transceiver mounted on the network interface card PCB. The card usually also contains the protocol control firmware and Ethernet Controller needed to support the Medium Access Control (MAC) data link protocol used by Ethernet.

• Repeater

Network repeaters regenerate incoming electrical, wireless or optical signals. With physical media like Ethernet or Wi-Fi, data transmissions canonly span alimited distance before the quality of the signal degrades. Repeaters attempt to preserve signal integrity and extendthe distance over which data can safely travel.

• Bridges

Network bridge connects multiple network segments at the data link layer (Layer 2) of the OSI model. In Ethernet networks, the te rm Bridge formally means a device that behaves according to the IEEE 802.1D standard. A bridge and switch are very much alike; a switch being a bridge with numerous ports. Switch or Layer 2 switch is often used interchangeably with Bridge.

• Gateway

Network gateway is an internetworkingsystem capable ofjoining together two networks that use different base protocols. A network gateway can be implemented completely in software, completely in hardware, or as a combination of both. Depending on the types of protocols they support, network gateways can operate at any level of the OSI model.

• Firewall

A firewall is a part of a computer system or network that is designed to block unauthorized access while permitting authorized communications. It is a device or set of devices configured to permit, deny, encrypt, decrypt, or proxy all (in and ut) computer traffic between different security domains based upon a set of rules and other criteria.

• Multilayer Switch
  
  

Multilayer switch (MLS) is a computer networking device that switches on OSI layer 2 like an ordinary network switch and provides extra functions on higher OSI layers.

• Digital Media Receiver
  

Digital media receiver (DMR) or digital media adapter (DMA) is a home entertainment device that can connect to a home network to retrieve digital media files (such as music, pictures, or video) from a personal computer or other media server and play them back on a home theater system or TV.The DLNA organisation refers to these devices as digital media renderers (DMR).

8. Example of Networking Cables and Their Functions. Post at least 10 w/ picture.

• Patch Cable

Is a twisted pair high signal integrity cable type often referred to as Cat5 or Cat-5. Most cables are unshielded, relying on the twisted pair design for noise rejection, and some are shielded. Category 5 hasbeen superseded by the Category 5e specification structured cabling for computer networks such as Ethernet, and is also used to carry many other signals such as basic voice services, token ring, and ATM (at up to 155Mbit/s, over short distances).

• Coaxial Cable

Is an electrical cable with an inner conductor surrounded by a tubular insulating layer typically of a flexible material with a high dielectric constant, all of which are surrounded by a conductive layer called the shield (typically of fine woven wire for flexibility, or of a thin metallic foil), and finally covered with a thin insulating layer on the outside. The term coaxial comes from the inner conductor and the outer shield sharing the same geometric xis. Coaxial cable was invented by English engineer and mathematician Oliver Heaviside, who first patented the design in 1880.

• Optical Fiber Cable

Is a cable containing one or more optical fibers. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed.

• Ethernet Crossover Cable

Is a type of Ethernet cable used to connect computing devices together directlywhere they would normally be connected via a network switch, hub or router, such as directly connecting two personal computers via their network adapters.

• UTP Cable

Unshielded Twisted Pair cable, UTP cable is a popular type of cable used in computer networking that consists of two shielded wires twisted around each other.

• STP Cable

Shielded Twisted-Pair cable, STPis a type of cable originally developed by IBM for Token Ring that consists of two individual wires wrapped in a foil shielding to help provide a more reliabledata communication.

• Power Line

Electric power transmission or "high voltage electric transmission" is the bulk transfer of electrical energy, from generating plants (historically hydroelectric, nuclear or coal fired but now also wind, solar, geothermal and other forms of renewable energy) to substations located near to population centers. This is distinct from the local wiring between high voltage substations and customers, which is typically referred to as electricity distribution.

• Plenum Cable

Plenum cable is cablethat is laid in the plenum spaces of buildings. The plenum (pronounced /ˈplɛnəm/) is the space that can facilitate air circulation for heating and air conditioning systems, by providing pathways for either heated/conditioned or return airflows. Space between the structural ceiling and the dropped ceiling or under a raised floor is typically considered plenum; however, some drop ceiling designs create a tight seal that does not allow for airflow and therefore may not be considered a plenum air-handling space. The plenum space is typically used to house the communication cables for the building's computer and telephone network

• Multi-Core Audio Cable
  

Multi-core audio patch cables, wiring looms and snakes with stage boxes for multi way audio signal transmission. A multicore cable has a stage-box on one end and the cable connectors, usually XLR, on the other end. The stagebox is sited on stage and the microphones and other audio sources are plugged in. These audio signals travel down the multicore cable to the mixer, where the signals are processed and mixed. This mix is then fed back along the multi-core cable return lines and sent to the on-stage amplifiers and monitors.