Networks- Schmetworks

This week has been a pretty extensive learning process for me as I am so utterly unfamiliar with networking and the whys and hows of it. It has, in the past, been a topic I avoided because there is a lot of associated jargon and some abstract ideast that have confused me. My attempt, this week, has been to lock down some jargon and try to get a solid understanding of how it all works. I've listed my 'ramblings' about networks and my discoveries here.

Servers
"A server is just a computer that sits on a network waiting for clients to ask for things." (http://digitalfire.com/dreamsite/whatisaserver.html). Servers are essentially normal computers. There are different types: mail, web, file servers. A file server is like the one I use at work, where we log on and access shared (or private) files. My desktop PC is the client.

A web server is a web host- servers around the world that rent out web space. They all have IP addresses. So does my PC, assigned by my Internet Service Provider (ISP). (http://www.wisegeek.com/what-is-a-web-server.htm). When I type in a URL, it sends a request to the website server's IP address, which in turn sends a response to my IP address. This allows me to download web pages from these servers.

LANs compared to WANs.
A Local Area Network is a series of computers joined together- either peer-to-peer or client-server architecture. A WAN is a series of connected LANs. (http://www.webopedia.com/TERM/L/local_area_network_LAN.html).

An Internetwork
Is simply connected networks (ie. The Internet).

Protocols
"There are rules governing how data is transferred over networks, how they are compressed, how they are presented on the screen and so on. These set of rules are called protocols." (http://voip.about.com/od/voipbasics/g/protocoldef.htm)

IP: Internet Protocol, defines a set of rules governing the way computers use IP packets to send data over the Internet or any other IP-based network. Along with addressing, routing is one of the main functions of the IP protocol.
TCP:Transmission Control Protocol, used for the reliable transmission of data over a network.
HTTP: Hypertext Transfer Protocol, used for transmitting and displaying information in the form of web pages on browsers.
FTP: File Transfer Protocol, used for file transfer (uploading and downloading) over the Internet
SMTP: Simple Mail Transfer Protocol, used for email
Ethernet: Used for data transmission over a LAN.
Wi-Fi: One of the wireless protocols.

TCP adn IP work together to create smooth internet transmissions- TCP ensures reliability- no loss of packets, correct ordering, acceptable delay and non-duplication of packets.

Packets
Data split in to bits for easy transmission. "These packets contain not only the data, but the sender's identification, the destination, and a little error-control information to make sure the data was not damaged." (http://library.thinkquest.org/C007645/english/1-networkcomm.htm)

ISPs
"The client typically connects to the Internet by calling the host computer of the Internet Service Provider (ISP). This computer is directly hooked up to the Internet; thus it is actually the real client." (http://library.thinkquest.org/C007645/english/1-networkcomm-1.htm)

Ports
"A server provides services on separate ports. eg. telnet www.unsw.edu.au 80" (lecture- Viveka). There are standard ports for particular services and a firewall restricts access to ports protocols.