COMP2 - Internet Flashcards
Internet Definition
The internet is a network of computer networks and computers using unique IP addresses and TCP/IP.
World Wide Web Definition
The WWW is a system of interlinked hypertext documents accessed via the internet.
Role of Packet Switching in the Internet
Packets flow between two end points that control communication.
The message is broken into smaller packets and all contain a source and destination address.
Router Definintion
A router is a speical switch that gets pacets from a host/router and sends it to another host/router.
End-to-End Principle
The two end computers are in control of communication accross the internet.
Open Architechture Principle
Allows the designers to freely design individual networks which are connect through a router-gateway.
Single logical Address Space Principle
Ensures every computer has a unique IP address, numbered using the IPv4 system; IPv4 allows 2^32 different addresses.
Domian Names
The Domain Name (System), Invented in 1983, is a name that identifies 1 or more addresses.
Fully Qualified Domain Names (FQDN)
Consists of a host ID and domain name. It uniquely identifies a host on this network.
Domain Name Sysytem Server Purpose
The DNS server translates FQDNs into IP addresses before connecting to a host.
Top Level Domian Names
Com, edu, org, net, gov.
URL
A Uniform Resource Locator identifies a resource by its network location. It’s a type of URI.
URI
A Uniform Resource Identifier specifies how to access a resource on the internet and identifies them by its name or location.
Server Definition
A software process that provides a service requested by a client.
Client Definition
A software process that requests and uses the services provided by a server.
Protocol Definition
A protocol is a set of pre-agreed rules, codes and signals for data exchange between systems.
Application Layer
Handles the details of a particular networking application.
Transport Layer
Establishes, supervises and maintains connection between 2 communication processes. It splits data into smaller bits to fit packets.
Network Layer
Addresses the packets with the source and destination addresses.
Link Layer
Handles the physical details of interfacing with the cable, including the network interface and device driver.
Port Definition
A port is an address for a software process.
Socket Definition
A socket is a combination of host IP addresses and a port number.
Well-Known Port Numbers
80 - Web Server
23 - Telnet Server
21 - FTP (File Transfer Protocol) Server
25 - SMTP (Simple Mail Transfer Protocol) Server
110 - POP3 (Post Office Protocol version 3) Server
HTTP Definition
The Hypertext Transfer Protocol is where a client machine sends a request message to the server which responds with a response message.
The most popular is textual data formatted using Hypertext Mark-up Language (HTML).
FTP Definition
File Transfer Protocol is an application layer protocol that enables files on 1 host to be copied to another.
POP3 Definition
Post Office Protocol version 3 is an application leyer protocol used to retrieve email from an email box on a remote server over a TCP/IP connection. Mail is held until a user requests it.
SMTP Definition
Simple Mail Transfer Protocol is used by email clients to send email where the message text is transfered to a mail server listening on port 25. The mail server delivers the mail to its destination.
