Assalamualaikum and have a nice day everyone. This is my first time blogging. First of all let me introduce myself. Hi my name is Syahida Binti Shamsudin and I’m famously known as Sam among my friends. I live in Taman Kota Jaya. I’m school at SMK Tun Habab and now sitting at 6R Al Farabi classes. I hope you all enjoys read my blog. Thank you.
Today I’m going to explain about communication technology. There are many technologies in the era globalization such as computer network, wired and wireless communication media and communication protocols.
TRANSMISSION MEDIA
Transmission media is a pathway that carries the information from sender to receiver.We use different types of cables or waves to transmit data. Data is transmitted normally through electrical or electromagnetic signals.
An electrical signal is in the form of current. An electromagnetic signal is series of electromagnetic energy pulses at various frequencies. These signals can be transmitted through copper wires, optical fibers, atmosphere, water and vacuum Different Medias have different properties like bandwidth, delay, cost and ease of installation and maintenance. Transmission media is also called Communication channel.
Types of Transmission Media
1. Wired or Guided Media or Bound Transmission Media: Bound transmission media are the cables that are tangible or have physical existence and are limited by the physical geography. Popular bound transmission media in use are twisted pair cable, co-axial cable and fiber optical cable. Each of them has its own characteristics like transmission speed, effect of noise, physical appearance, cost etc.
2. Wireless or Unguided Media or Unbound Transmission Media: Unbound transmission media are the ways of transmitting data without using any cables. These media are not bounded by physical geography. This type of transmission is called Wireless communication. Nowadays wireless communication is becoming popular. Wireless LANs are being installed in office and college campuses. This transmission uses Microwave, Radio wave, Infra red are some of popular unbound transmission media.
COMPUTER NETWORK
A computer network or data network is a telecommunications network that allows computers to exchange data. In computer networks, networked computing devices pass data to each other along data connections. The connections (network links) between nodes are established using either cable media or wireless media. The best-known computer network is the Internet.
Network computer devices that originate, route and terminate the data are called network nodes. Nodes can include hosts such as personal computers, phones, servers as well as networking hardware. Two such devices are said to be networked together when one device is able to exchange information with the other device, whether or not they have a direct connection to each other.
Computer networks support applications such as access to the World Wide Web, shared use of application and storage servers, printers, and fax machines, and use of email and instant messaging applications. Computer networks differ in the physical media used to transmit their signals, the communications protocols to organize network traffic, the network's size, topology and organizational intent.
Ø Network architecture
A network architect is responsible for creating, maintaining and modifying an IP network's hardware, software and virtualized components. Network architects are not only required to maintain expert-level knowledge regarding network hardware and software technology, but they must also be able to translate a network's technological requirements into solutions that benefit a given business.
Ø Topology
Network topology is the interconnected pattern of network elements. A network topology may be physical, mapping hardware configuration, or logical, mapping the path that the data must take in order to travel around the network.
Ø Type of network - local-area networks (LANs)
- wide-area networks (WANs)
- campus-area networks (CANs)
- home-area networks (HANs)
Ø Type of communication technology
- Short Message Services (SMS), commonly referred to as texting
- Video conferencing and chat services, like Skype
- Blogs and wikis, like WordPress and Mediawiki
- Microblogging services like TwitterDocument and calendar sharing services like Google Docs
- Postal and shipping services
WIRED
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| Coaxial cable |
COAXIAL CABLE
A coaxial cable is armored cable with a sheathed plastic that contains two concentric conductors or wires. One is typically an inner cooper straight wire covered with a sheathed plastic (insulation) and the second wire is typically a mesh shielding protected with an outer insulation of plastic. It is also known as a co-ax. This design provides the coaxial cable with a special advantage: electrical interference is reduced because the two conductors are shielded and confined separately.
Its main uses are in transmission lines to carry signal or data. Coaxial cables are used primarily for TV standard-definition connection to transfer television signal, and for computer network (internet connection) such as Ethernet to carry data. Because is much less susceptible to interference, it might carry much more data. Also, it is used to carry radio signal, video signal, and measurement signal.
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| Fibre optic |
FIBRE OPTIC
The modern telecommunications use electricity, light or radio to send sounds, images and data. The fiber optic, instead of propagating sound waves, transmits data in form of light pulses with the great advantage which the luminous pulsations are transmitted without interruption. The transportation of information is by light waves not by electricity, this avoid the interefence of electrical noise and degradation of the signal. In conclusion, it is a medium for carrying data in the form of light.
One of the advantages of optical fiber system is that can carry the equivalent of an encyclopedia set (24 volumes, approximately 40 millions words) of information in a single second. Other benefits include long distance transmission of data (more than 100 kilometer), it is dielectric (non-conductivity), easy to install, and long continuous lengths (single-mode cable lengths up to 12 km) among others.
The fiber optic consist of one or several thin fibers of glass or plastic of 50 to 125 micrometers of diameter, we can say that it more or less of the thickness of a hair. The fiber optic cable is made up of a cylindrical region called nucleus, through the light is propagated, the external zone of the coaxial nucleus is called coating. This coating is a plastic cover or made of other materials that protect it against the humidity.
One of the advantages of optical fiber system is that can carry the equivalent of an encyclopedia set (24 volumes, approximately 40 millions words) of information in a single second. Other benefits include long distance transmission of data (more than 100 kilometer), it is dielectric (non-conductivity), easy to install, and long continuous lengths (single-mode cable lengths up to 12 km) among others.
The fiber optic consist of one or several thin fibers of glass or plastic of 50 to 125 micrometers of diameter, we can say that it more or less of the thickness of a hair. The fiber optic cable is made up of a cylindrical region called nucleus, through the light is propagated, the external zone of the coaxial nucleus is called coating. This coating is a plastic cover or made of other materials that protect it against the humidity.
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| Twisted pair |
A twisted pair wire is a copper wire that connects your personal computer at home or at work to the telephone line. It is called a twisted wire because two wires that are insulated to prevent wirecrossing are twisted together. Have you ever been on the phone to a friend and all of a sudden you pick up someone elses conversation? Many of you have and this may be due to a snag or untwist of the twisted copper pair wire. The insulation and twist help reduce the telephone lines from crossing (William.B & Sawyer.S, 2007. Using Information Technology. The McGraw-Hill Publishing Inc: New York). Since the twisted pair wire is made of copper it is deemed to be the least expensive media communication tool
WIRELESS
Wireless communication is the transfer of information between two or more points that are not connected by an electrical conductor.
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| Microwave |
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| Satellite |
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| Bluetooth |
The most common wireless technologies use radio. With radio waves distances can be short, such as a few meters for television or as far as thousands or even millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants(PDAs), and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mice, keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones.
Somewhat less common methods of achieving wireless communications includes the use of other electromagnetic wireless technologies, such as light, magnetic, or electric fields or the use of sound.
COMMUNICATION PROTOCOL
In telecommunications, a communications protocol is a system of digital rules for data exchange within or between computers.
Communicating systems use well-defined formats for exchanging messages. Each message has an exact meaning intended to elicit a response from a range of possible responses pre-determined for that particular situation. Thus, a protocol must define the syntax, semantics, and synchronization of communication; the specified behavior is typically independent of how it is to be implemented. A protocol can therefore be implemented as hardware, software, or both. Communications protocols have to be agreed upon by the parties involved. To reach agreement a protocol may be developed into a technical standard. A programming language describes the same for computations, so there is a close analogy between protocols and programming languages: protocols are to communications as programming languages are to computations.
TCP/IP
Transmission Control Protocol/Internet Protocol (TCP/IP) is the language a computer uses to access the Internet. It consists of a suite of protocols designed to establish a network of networks to provide a host with access to the Internet.
TCP/IP is responsible for full-fledged data connectivity and transmitting the data end-to-end by providing other functions, including addressing, mapping and acknowledgment. TCP/IP contains four layers, which differ slightly from the OSI model.
The technology is so common that you would rarely refer to somebody use the full name. In other words, in common usage the acronym is now the term itself.
SMTP
Simple Mail Transfer Protocol (SMTP) is the standard protocol for email services on a TCP/IP network. SMTP provides the ability to send and receive email messages.
SMTP is an application-layer protocol that enables the transmission and delivery of email over the Internet. SMTP is created and maintained by the Internet Engineering Task Force (IETF).
SMTP is one of the most common and popular protocols for email communication over the Internet and it provides intermediary network services between the remote email provider or organizational email server and the local user accessing it.
SMTP is generally integrated within an email client application and is composed of four key components:
Local user or client-end utility known as the mail user agent (MUA)
Server known as mail submission agent (MSA)
Mail transfer agent (MTA)
Mail delivery agent (MDA)
SMTP works by initiating a session between the user and server, whereas MTA and MDA provide domain searching and local delivery services
AppleTalk
AppleTalk is a set of proprietary networking protocols developed by Apple for their computer systems. AppleTalk was included in the original Macintosh released in 1984. In 2009, it became unsupported with the release of Mac OS X v10.6 and was dropped in favor of TCP/IP networking, allowing Apple computers to use the same standard to communicate with other computers.
The design of AppleTalk followed the OSI Model of protocol layering with two protocols aimed at making the system completely self-configuring:
AppleTalk Address Resolution Protocol (AARP): Allowed hosts to automaticaly generate their own network addresses
Name Binding Protocol (NBP): A dynamic system that maps network addresses to user-readable names.
AppleTalk was revolutionary and easy to configure in its day. However, with the rise of Internet-based protocols and their standardization, the need for a proprietary system quickly declined. If Apple had not conformed to other standards, they were in danger of losing the competition. Hence, they finally dropped AppleTalk in favor of TCP/IP. Apple supported AppleTalk for older devices for a while. However, the last Mac OS to support AppleTalk was OS X v10.5.
AppleTalk used a 4-byte address system and used completely self-configuring protocols. The address resolution protocol allowed hosts to generate their own address automatically. The name binding protocol allowed the system to dynamically map the network address to user-readable names of terminals.
An AppleTalk address consisted of a two-byte network number, a one-byte node number, and a one-byte socket number. Only the network number needed configuration, which was obtained from a router. This allowed for a total of 32 devices to be connected to the network and operated at 230.4 KBps with the devices being up to 1000 feet apart.
Netbeui
NetBIOS Extended User Interface (NetBEUI) is a non-routable transport protocol that provides network/network layer support while optimizing small to medium-sized operating systems (OS). NetBEUI works for internal LAN communication.
NetBEUI is the best performance choice for communication within a single LAN. Because, like NetBIOS, it does not support the routing of messages to other networks, its interface must be adapted to other protocols such as Internetwork Packet Exchange or TCP/IP. A recommended method is to install both NetBEUI and TCP/IP in each computer and set the server up to use NetBEUI for communication within the LAN and TCP/IP for communication beyond the LAN.
References:
http://en.wikipedia.org/wiki/Computer_network
http://www.techterms.com/definition/wired
http://en.wikipedia.org/wiki/Communications_protocol
http://en.wikipedia.org/wiki/wireless
http://www.techopedia.com/
http://ecomputernotes.com/computernetworkingnotes/communication-networks/what-is-transmission-media-and-types-of-transmission-media
http://ecomputernotes.com/computernetworkingnotes/communication-networks/what-is-transmission-media-and-types-of-transmission-media
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