Computer and ICT Networks

Tweets by @markusgattol

Status: Just notes so far

Last changed: Monday 2013-09-30 13:07 UTC

Abstract:

A computer network is an interconnection of a group of computers. Networks may be classified by what is called the network layer at which they operate according to basic reference models considered as standards in the industry such as the four-layer Internet Protocol Suite model. While the seven-layer OSI (Open Systems Interconnection) reference model is better known in academia, the majority of computer networks nowadays use the IP (Internet Protocol) Suite as their network model. The main purpose why this page came to life is to provide theoretical background for the reader in order to understand information onto other pages of the Network context. Those other pages will cover how to deal with DebianGNU/Linux and various high-end home as well as low-end enterprise equipment when it comes to set up, configure and maintain a state of the art computer network.

Table of Contents

OSI Reference Model

Internet Protocol Suite

Computer Networks

The Internet
VLAN (Virtual Local Area Network)
Ethernet
Common Connection Technologies for the Last Mile
Subnetwork
MAC Address

Packet Switching in Computer Networks

Circuit vs. Virtual Circuit vs. Package based Communications
Switching vs. Routing
Switch vs. Hub

DNS (Domain Name System)

DNS Record Types
Miscellaneous

OSI Reference Model

Internet Protocol Suite

Computer Networks

The Internet

Private Network

Go here for more information.

Subnetting, Supernetting and CIDR (Classless Inter-Domain Routing)

Go here for more information.

VLAN (Virtual Local Area Network)

I dedicated a whole single page to the VLAN subject simply because the subject is thus important to deserve one on its own.

Ethernet

Common Connection Technologies for the Last Mile

Wireless

PPPoE (Point-to-Point Protocol over Ethernet)

Subnetwork

MAC Address

Packet Switching in Computer Networks

When talking about packet switching with regards to computer networks, we are then talking about packet switching in TCP/IP based networks.

Circuit vs. Virtual Circuit vs. Package based Communications

Switching vs. Routing

Switch vs. Hub

An Ethernet hub, or repeater, is a fairly unsophisticated broadcast device, and rapidly becoming obsolete. Hubs work on OSI (Open Systems Interconnection) layer 1 also known as physical layer. Hubs do not manage any of the traffic that comes through them. Any packet entering a port is broadcast out or repeated on every other port, save the port of entry. Since every packet is repeated on every other port, packet collisions result, which slows down the network.

Hubs have actually become hard to find, due to the widespread use of switches. There are specialized applications where a hub can be useful, such as copying traffic to multiple network sensors. There is no longer any significant price difference between a hub and a low-end switch.

Hub

I am not going to cover hubs since I consider them (as most do) obsolete.

Network Switch

DNS (Domain Name System)

More information can be found here.

DNS Record Types

Go here for more information.

Miscellaneous

DNSSEC

Canonical Name respectively FQDN (Fully Qualified Domain Name)

Go here.

URL respectively URI (Uniform Resource Identifier)

See here and here.

`dig`, a DNS look up Utility

http://www.madboa.com/geek/dig/

OSI Reference Model

Internet Protocol Suite

Computer Networks

The Internet

Private Network

Subnetting, Supernetting and CIDR (Classless Inter-Domain Routing)

VLAN (Virtual Local Area Network)

Ethernet

Common Connection Technologies for the Last Mile

Wireless

PPPoE (Point-to-Point Protocol over Ethernet)

Subnetwork

MAC Address

Packet Switching in Computer Networks

Circuit vs. Virtual Circuit vs. Package based Communications

Switching vs. Routing

Switch vs. Hub

Hub

Network Switch

DNS (Domain Name System)

DNS Record Types

Miscellaneous

DNSSEC

Canonical Name respectively FQDN (Fully Qualified Domain Name)

URL respectively URI (Uniform Resource Identifier)

dig, a DNS look up Utility

`dig`, a DNS look up Utility