Sunday, March 18, 2007

My first Web-page

I just put my first webpage. Link will show error page. Because I didn't create other web pages yet. ( ^^ )

http://students.mim.iml.uts.edu.au/users/10355042/Project/index.php

Friday, March 9, 2007

Week 2 ( Networks )

A. Network
Following webpage shows good information of network.
http://en.wikipedia.org/wiki/Computer_network
Computer network is two or more computers connected together using a telecommunication system for the purpose of communcating and sharing resources.
There are many types of networks: LAN, CAN, MAN, WAN, Internet, Intranet, Extranet. Especially, Internetwork is two or more networks or network segments connected using devices that operate at layer 3 (the 'network' layer) of the OSI Basic Reference Model, such as router.
B. Protocol
Following webpage shows good information of Protocol.
http://en.wikipedia.org/wiki/Protocol_(computing)
In computing, a protocol is a convention or standard that controls or enables the connection, communication, and data transfer between computing enpoints. In its simplest form, a protocol can be defined as the rules govering the syntax, semantics, and synchronization of communication. Protocols may be implemented by hardware, software, or a combination of the two.
There are many common protocols like HTTP, POP3, SMTP, FTP, IP, DHCP, IMAP...
Especially, HTTP( Hypertext Transfer Protocol ) is a method used to transfer or convey information on the World Wide Web. Its original purpose was to provide a way to publish and retrieve HTML pages.
The Open Systems Interconnection Basic Reference Model(OSI Reference Model or OSI Model for short) is a layered, abstract description for communications and computer network protocol design, developed as part of the Open Systems Interconnection initiative. It is also called the OSI seven layer model.
Layer 1: Physical layer
Layer 2: Data Link layer
Layer 3: Network layer
Layer 4: Transport layer
Layer 5: Session layer
Layer 6: Presentation layer
Layer 7: Application layer
http://en.wikipedia.org/wiki/OSI_model. This is good webpage explains what the OSI model is.
C. Server
In information technology, a server is a computer system that provides services to other computing systems-called clients-over a computer network. The term server can refer to hardware( such as a Sun computer system) or software(such as an RDBMS server).
Servers frequently host resouces that they make available on a controlled and shared basis to client computers, such as printers and file systems. This sharing permits better access control and can reduce costs by reducing duplication of hardware.
Almost the entire structure of the Internet is based upon a client-server model. Many millions of servers are connected to the Internet and run continuously throughout the world.
Among the many services provided by Internet servers are: the Web; the Domain Name System; electronic mail; file transfer; instant messaging; streaming audio and video, online gaming, and countless others. Virtually every action taken by an ordinary Internet user requires one or more interactions with one or more servers.

D. Client
A client is a compouter system that accesses a service on another computer by some kind of network. The term was first applied to devices that were not capable of running their own stand-alone programs, but could interact with remote computers via a network.
The client-server model is still used today on the Internet, where a user may connect to a service operating on a remote system through th einternet protocol suite. Web browsers are clients that connect to web servers and retrieve web pages for display. Most people use e-mail clients to retrieve their e-mail from their internet service provider's mail storage servers.
Types of Client
Fat client, Thin client, Hybrid client
E. The Internet
http://en.wikipedia.org/wiki/Internet
The Internet is the worldwide, publicly accessible network of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol(IP). It is a "network of networks" that consists of milliions of smaller domestic, academic, business, and government networks, which together carry various information and services, such as electronic mail, online chat, file transfer, and interlinked Web pages and other documents of the World Wide Web.

Common uses of the Internet
E-mail, The World Wide Web, Remote access, Collaboration, File sharing, Streaming Media, Voice telephony