-- About Computer Networking --
A network of computers is when two or more computers are connected to each other and can exchange information. Computer networks range in
size from a small home network to large corporations to the largest network in the world, the Internet. Computers must have
networking capabilities and if more then two computers are being connected then there must be a router or switch used to connect
them together. Networking computers together allows for the exchanging of information between computers and can help people in a work
environment communicate faster and more efficiently. Networking allows for things such as: Electronic Mail, File Sharing, Printer
Sharing, Video Conferencing, Voice over Internet Protocol (VoIP) Telephone Systems, and company web sites.
Computer networking was not something the average person worried about in their home until the Internet because something everybody
wanted in their house. Since the explosion of the Internet people have started to create home networks with many devices in their homes
for easy access to the Internet through laptops, televisions, and game consoles. More and more consumer devices are beginning to become
network capable such as Printers, Mobile Phones, Game Consoles, and Televisions.
Computer networks are diagramed using something called a "topology" to show how computers are connected to one another. Note that the
physical layout of the network does not reflect the diagram. It is simply used as a way to understand the type of the network. The different
Topology's are: Star, Ring, Bus, and Mesh. In a star network all nodes(PC's or devices) are connected to a central piece of equipment. A
star topology is the most used today. In a ring topology each node is connected to it's neighboring node to it's left and right. A bus
topology contains a medium for the nodes to connect to. All nodes connect to this medium in the network. In a mesh topology "each node
is connected to an arbitrary number of neighbors in such a way that there is at least one traversal from any node to any other."
Computers are able to talk to each other on a network through something called a Protocol. Think of a protocol as a language. If both
computers are able to speak the same language then they can communicate. The most popular networking protocals today is is the Internet
Protocol Suite or IP. One of the most commonly used componants of the IP Suite is called Transmission Control Protocol. This is commonly
refered to as TCP/IP. TCP/IP is used by almost everything network in the world and that includes the Internet. Other examples of protocols
that one may run in to are: UDP, FTP, IMAP, SMTP, POP3, SSH, SSL, DHCP, and DNS. Do not worry about what each one does or stands for. Just
know that they all are part of networking and some control your email, how files are transfered at your work, how web sites are found on the
Internet, and how you can connect to the Internet without setting anything up. Without these protocols or languages then computers in a
network would have no way of talking to one another.
There are different scales of computer networks. The different types are: LAN, MAN, and WAN. Most people will only use a Local Area
Network(LAN) in their home and/or office. This means that the network does not extend past the home or office building the network has
been setup in. City's use what is called a Metropolitan Area Network(MAN) to network the city government buildings, schools, library's,
etc. together. MAN networks do not extend past the city limits. The largest of the three, a Wide Area Network(WAN), is what
enterprise level corporations use and what the Internet is based on. A Wide Area Network can connect to any where in the world and
is connected by means of the Internet Service Provider(ISP). The ISP will give the user an IP address that is used to find the
person on the Internet. Special WAN routers are used to control who has access to your network and what they will have access to.
There are other types of specialized networks such as Storage Area Network and Virtual Private Networks that are more advanced
serve a specific purpose. If you are interested in learning about them follow the Wikipedia link at the bottom of the page. Below are
some FYI's about networking.
- An ISP such as Comcast, Verizon, Qwest, or AT&T is needed to connect to the Internet.
- Home networks using more then one electronical device will need a router or switch to connect all devices together.
- Networks can be either Wired or Wireless.
- Wireless networks can be accessed by anyone with a wireless networking card unless secured.
- Wireless security should be set as WPA2 if possible. WEP and WPA are not as strong and can be more easily hacked.
- When bought, networking equipment of the same manufacter and model number share the same default settings and should be
changed to better secure your information.
- Routers and Switches use something called a Network Address Table(NAT) as a guide on where to send information.
- Information being exhanged is cut into small pieces called packets. Each packet along with other information contain
an origin and destination in the form of an IP address so that the information does not get sent to other computers on the same network.
Packets also contain a packet number so the receiving computer knows what order to piece the packets back together in.
- Most Routers, Switches, and PC's contain Firewalls that are used to keep unwanted traffic out of your network.
- Unless configured with strict rules, Firewalls can be bypassed by skilled hackers.
- Devices and Computers connected to the routers and switches use private IP address numbers that are hidden behind
the ISP's IP Address that was assigned to you.
- Computers and other devices being networked are commonly connected with Category 5 Cable
- Long distance connections typically use Coaxial Cable or
Fiber Optic Cable.
- WAN and MAN connections are usually established through the Internet lines that currently exist.
- Networks have ports much like a waterfront community. They number 0-65,535 and some ports are either well-known or registered. Others
are for personal/private use. Firewalls control these ports, and if ports are left open hackers can easily find their way in to your
- Virtual Private Networks can be established by setting up a VPN server that creates a private tunnel through your Internet connection
allowing for data to be exchanged privately and securely between parties.
- A private network with access to the Internet but does not give the Internet access to it's resources is called an Intranet.
- A Intranet that is shared with other select people outside of the network is called an Extranet. This happens when large
corporations need to share information with one another.
was used as a source for this information. Thank you
to all those who contributed to it.