WHAT IS COMPUTER NETWORKING
The term NETWORKING could have different definitions depending on how
you mean it and what you are talking about. In a social sense networking
could mean the act of getting to know and interact with people
especially when they share a common interest with you. This is no
different in the ICT world, Just put computers where you have people in
the first definition. Networking is a connection of computers and other
telecommunication devices in order to share data and computer hardware
resources example printers, scanners etc.Two devices are not connected
unless they are able to share information with each other.
To mark the beginning of a newly born Advanced Research Projects Agency Network (ARPANET) In 1969, four institutions "Stanford Research Institute at Menlo Park, California(50kb/s), University of California at Santa Barbara, University of Utah and University of California at Los Angeles, were connected using a 50kilobit per seconds) network circuit" APARNET was one of the world's first operational packet switching networks, the first network to implement TCP/IP, and it is a framework that was used to develop a global network now known as the internet.ARPANET was widely used for research projects especially military until it was replaced by National Science Foundation network (NSFNET) in 1990 one of the reasons for this was that NSFNET supported both TCP/IP and OSI protocol which was introduced by ISO to standardize and regulate network development and design due to increasing numbers of conflicting network vendors. The OSI reference model was introduced to help networks to communicate with each other Irrespective of the vendor(network designer) also with the introduction of OSI reference model, it is now possible for network devices manufactured by different vendors, to be used together on a single network. Attached Resource Computer network ARCnet a token passing network that was first used to share storage devices was developed by John Murphy in 1976.
since 1970s significant materials, hand outs and publications about ethernet and other network developements have been written and published by many network researchers and engineers some of these authors include; David Boggs and Robert Metcalfe who published thier first material on Ethernet: "Distributed Packet Switching for Local Computer Networks" Leonard Kleinrock at MIT published the first paper on packet switching theory on May 31, 1961.In December 1968, Elmer Shapiro with SRI released a report "A Study of Computer Network Design Parameters." Based on this work and earlier work done by Paul Baraon
Remember that I mentioned earlier on the second paragraph that arparnet ran on a 50kb/s data speed, which is relatively very low compared to today's 100mb to 1gb network data speed. well things got better in 1995 when Ethernet speed was upgraded from 10Mb/s to 100Mb/s. By 1998, Ethernet could support transmission speeds in Gigabit using twisted pair cables, fiber optics, electromagnetic waves (wirless) as mediums of transmission.
A Brief History
At least every thing originates from somewhere huh? networking came into existence in the late 1940s when the United States air defense felt increasing need to control and communicate with its air crafts from ground and this need was met in the late 1950's when a large scale integrated ground control system used for controlling and signaling of us military air craft "Semi-Automatic Ground Environment (SAGE)" a US military radar was invented by lincoln Laboratories as one of the first communicating computer systems and was operational by 1963. It remained in continuous operation until 1983. since then, subsequent developments such as "Intergalactic Computer Network" a working group developed by J.C.R. Licklider in 1962, In 1964, researchers at Dartmouth developed the Dartmouth Time Sharing System for distributed users of large computer systems, this year was significant because in the same year, at Massachusetts Institute of Technology, a research group supported by General Electric and Bell Labs used a computer to route and manage telephone connections which marks the birth of packet routing and to add to that, network systems which used packets to transfer information between computers over a network(packet switched network) was used and conceptualizes by different individual one of them named Donald Davies a Welsh computer scientist in the 1960s. 1965 marked the birth of wide area network (WAN) by two amazing computer geeks Lawrence G. Roberts and Thomas Marill. The the first fully computerized telephone was developed by Western Electric.To mark the beginning of a newly born Advanced Research Projects Agency Network (ARPANET) In 1969, four institutions "Stanford Research Institute at Menlo Park, California(50kb/s), University of California at Santa Barbara, University of Utah and University of California at Los Angeles, were connected using a 50kilobit per seconds) network circuit" APARNET was one of the world's first operational packet switching networks, the first network to implement TCP/IP, and it is a framework that was used to develop a global network now known as the internet.ARPANET was widely used for research projects especially military until it was replaced by National Science Foundation network (NSFNET) in 1990 one of the reasons for this was that NSFNET supported both TCP/IP and OSI protocol which was introduced by ISO to standardize and regulate network development and design due to increasing numbers of conflicting network vendors. The OSI reference model was introduced to help networks to communicate with each other Irrespective of the vendor(network designer) also with the introduction of OSI reference model, it is now possible for network devices manufactured by different vendors, to be used together on a single network. Attached Resource Computer network ARCnet a token passing network that was first used to share storage devices was developed by John Murphy in 1976.
since 1970s significant materials, hand outs and publications about ethernet and other network developements have been written and published by many network researchers and engineers some of these authors include; David Boggs and Robert Metcalfe who published thier first material on Ethernet: "Distributed Packet Switching for Local Computer Networks" Leonard Kleinrock at MIT published the first paper on packet switching theory on May 31, 1961.In December 1968, Elmer Shapiro with SRI released a report "A Study of Computer Network Design Parameters." Based on this work and earlier work done by Paul Baraon
Remember that I mentioned earlier on the second paragraph that arparnet ran on a 50kb/s data speed, which is relatively very low compared to today's 100mb to 1gb network data speed. well things got better in 1995 when Ethernet speed was upgraded from 10Mb/s to 100Mb/s. By 1998, Ethernet could support transmission speeds in Gigabit using twisted pair cables, fiber optics, electromagnetic waves (wirless) as mediums of transmission.
What is a Network
A connection of two to three devices across a small or large area is a network. It is a described as a collection of connected devices such as computers, printers, scanners servers, and other network applications, aimed at sharing and transferring data and information from one point to another.Physical Components Of A Network
Physical components of a network are those devices which are used to setup the physical parts of the network. All this devices must be setup together and complete before the network can function well. physical devices use mac address as their unique address. These devices are classified into four major groups. End
Devices:
This class includes your personal computers (PCs), network
server machines, printers, mobile devices such as phones and laptops
etc. They serve as end points in the network. They especially contain
user applications/ software which is responsible for initiating
connection with other devices, also sending and receiving data e.g TCP,
UDP and browser applications etc.
Interconnections:
This consist of components (medium) that
physically transmits data (though electric signal) from one device to
another (point to point) in the network. These components includes:
Network Interface Cards: NIC cards which acts as an interface which translates data created by the computer into a format that can be transmitted over the LAN (Local Area Network). They are basically two types of NIC adapters;
Network Interface Cards: NIC cards which acts as an interface which translates data created by the computer into a format that can be transmitted over the LAN (Local Area Network). They are basically two types of NIC adapters;
The Local Area Network cable adopter: This uses etternet cables
for data transmission. The cable is plugged into the computer using the
rj45 or the rj11 connections which is plugged into a female jack on the
host device.
Wireless Network Adapter: This adapter uses wireless medium (air/space) as its medium of data transmission which is in form of electromagnetic wave. Some of the devices have both wired and Ethernet connectors although it is not common among mobile devices since they are mostly carried around so they make use of wireless connections.
Note that Ethernet LAN adapter mac address and the wireless mac address are not the same, each adapter has its physical (MAC) address although you can have both components at the same time on your computer.
Wireless Network Adapter: This adapter uses wireless medium (air/space) as its medium of data transmission which is in form of electromagnetic wave. Some of the devices have both wired and Ethernet connectors although it is not common among mobile devices since they are mostly carried around so they make use of wireless connections.
Note that Ethernet LAN adapter mac address and the wireless mac address are not the same, each adapter has its physical (MAC) address although you can have both components at the same time on your computer.
Network media: such as Ethernet cable fiber optics and wireless medium.
Connections: e.g RJ11 RJ45, CAT4, 5,6 are most common connectors. They act as a sockets and plug which are used to connect host devices.
Connections: e.g RJ11 RJ45, CAT4, 5,6 are most common connectors. They act as a sockets and plug which are used to connect host devices.
Switches:
Are intelligent devices used for switching data
within the LAN. They are devices that provide network attachment
(connections) between end systems. The switch maintains a mac address
table of every system that is on the network, it uses the information to
forward data frames to the right host on the network.
Router:
This is more intelligent than the switch. It contains the
mother board, RAM and CPU (processor). the router has the major
characteristics of a computer.The router has a very important role to
play on a network especially when the host on a particular LAN wants to
send data outside the network to another network. The router uses different routing protocols to update the
routing information on its routing table to determine the best path to
take when routing data from one network to another.
CHARACTERISTICS OF A NETWORK
The
following are the characteristics that can be used to describe a network.
Speed: It is mostly known as bandwidth. This is a very common characteristic of a network which describes the rate of data flow per second on a network. It describes how fast data is been transmitted over a network. The data transmission for a common LAN ranges from 10mb/s to 100mb/s.
Cost: Of course, nothing is free ever in “Free Town” cost here as an characteristics of a network indicates how much money, time and labour you have to spent in purchasing the equipment, setting up the network and also maintaining the network.
Security: data integrity and security is a vital issue and should not escape your minds when implementing or taking actions that may affect the network. The level of security on your network will determine how secure your network is from inside or outside attackers. Security also indicates how safe the data in your network is even during data transmission within or outside the network.
Availability: Your network service how available is it to you? Does it go off or timeout more often than it should? Network availability is a characteristic that measures the total time in minutes that a network will be available to you when needed in a year.
Take for an example a network that is meant to be used 24/7 365days in a year, you calculate the availability by dividing the time it is actually available by the total time in minutes in a year and then multiplying by 100 to get the percentage availability.
Let’s say that a network is unavailable for 40 minutes in a
year due to network outages, the percentage availability of the network will
be;
[(a - b)/a ] * 100
Where;
“a” is the total minutes in a year(525600mins), “b” is the total downtime in minutes for the
year(452mins),
Therefor
[(525600-452)/(525600)]*100 = 99.9% available
Types Of A Network
There are basically Three types of Network
Local Area Networks(LAN)
This type
of network covers small geographic areas.
They are sited in small
locations such as Homes, small offices, a particular building or floor.
This type of network is private in nature and owned by small or big
organizations as such host devices on this network carries private IP
addresses most of them unregistered. This network is designed to connect
and share data and other resources within an organization, home or a
small work area.
Wide Area Networks (WAN)
A typical example of this is the internet also known as a public network. This network contains the world wide web (WWW) it covers a very wild geographical area. It is an interconnection of many LANs across a very wide geographic location. several technologies including high tech hardware devices and sophisticated software functioning is needed to implement a well functioning WAN. To connect to a WAN, you have to use the services of ISPs, space satellites, Mobile and telephone companies, or even cable companies. This is so because this companies have devices and equipments that can connect your LAN devices to other network devices that are separated by a wide geographic area. Host devices connected to this network are often referred to as being in a high risk zone since your computer might get infected, or hacked at a cause of trying to get data and information from other unprotected or virus infected networks, Hence the need for firewall on your network devices is important.
Metropolitan Area Network (MAN)
This type of network tlinks LANs and network devices that are geographically separated but are also located within the same metropolitan area. an example of this kind of network is when an organization has many branch offices and a head office within a particular country but in different locations. being fully aware that each offices has its own LAN now communication, data and resources will be shared from the head offices to the branch offices by linking these LANs together. The nettwork established between this offices is known as a MAN.Network Benefits
The benefits of a network cannot be overstated in the world of networking today. Although I am only going to talk about a few and major resource sharing benefits alone on this article. Although the resources sharing benefit of a network host may be regulated by the organisation policies (sometimes regulated using the organisations staff hierachy and positions held by the staff), but as a member of a particular network , you should be able to benefit from atleast one of the following;1. Resources: resources on a network includes printers, scanners, input and output devices and other peripherals or some times helps you gain access to public network and the world wide web(www).
2. Data backup: Some networks includes backup devices such as tapes, CDs and multiple data storage devices which enables you to backup an organizations data for future or emergency reference which ensures business continuity and other file-backup benefits in the organization.
3. Network allows you to share storage devices on your network. There are three different ways which networks share their storage devices; Directly attached storage(DAS) allows you to physically attach the storage device directly to your computer. Network attached storage (NAS) allows you to store data using a special network device that is attached to the network. Storage area networks (SAN) this method provides you with series of interconnected storage devices.
4. Files and applications sharing; with the help of tcp, UDP, FTP, TFTP and others sharing of data and application programes on a network is possible. Now one application program can be shared by many host on a network and files can be transmitted from one host to another, therefore making data more easily available, promoting more efficient collaboration on work projects.
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