Computer Networking

Computer networks are interconnections of many computers. Computers in a network share resources such as electronic mail, bulletin boards, and access to unique databases. Think of them as information highways for data. Networks are changing the computing paradigm from "number-crunching" to communicating. They have spawned a number of industries and helped organizations provide information and communication services to remote customers. In a computer network the individual stations, called nodes, may be computers, terminals, or communication units of various kinds. Networks that are contained within a building or a small geographical area are called local area networks. The largest network connecting computers spread across the globe, is yes, the Internet. Know all the little things you should, about computer networking.

Just for fun...

Advantages and Disadvantages of Different Network Topologies

Network topologies describe the ways in which the elements of a network are mapped. They describe the physical and logical arrangement of the network nodes. Let us look at the advantages the different network topologies offer and get to know their shortfalls.


Bus Topology

Advantages of Bus Topology
It is easy to handle and implement.
It is best suited for small networks.

Disadvantages of Bus Topology
The cable length is limited. This limits the number of stations that can be connected.
This network topology can perform well only for a limited number of nodes.

Ring Topology

Advantage of Ring Topology
The data being transmitted between two nodes passes through all the intermediate nodes. A central server is not required for the management of this topology.

Disadvantages of Ring Topology
The failure of a single node of the network can cause the entire network to fail.
The movement or changes made to network nodes affects the performance of the entire network.

Mesh Topology

Advantage of Mesh Topology
The arrangement of the network nodes is such that it is possible to transmit data from one node to many other nodes at the same time.

Disadvantage of Mesh Topology
The arrangement wherein every network node is connected to every other node of the network, many of the connections serve no major purpose. This leads to the redundancy of many of the network connections.

Star Topology

Advantages of Star Topology
Due to its centralized nature, the topology offers simplicity of operation.
It also achieves an isolation of each device in the network.

Disadvantage of Star Topology
The network operation depends on the functioning of the central hub. Hence, the failure of the central hub leads to the failure of the entire network.

Topology

What is a network topology? In communication networks, a topology is a usually schematic description of the arrangement of a network, including its nodes and connecting lines. There are two ways of defining network geometry: the physical topology and the logical (or signal) topology.


The Physical Topology...
           The physical layout of devices on a network. Every LAN has a topology, or the way that the devices on a network are arranged and how they communicate with each other. The way that the workstations are connected to the network through the actual cables that transmit data -- the physical structure of the network -- is called the physical topology. The logical topology, in contrast, is the way that the signals act on the network media, or the way that the data passes through the network from one device to the next without regard to the physical interconnection of the devices.

 The Logical Topology...
            Also called signal topology. Every LAN has a topology, or the way that the devices on a network are arranged and how they communicate with each other. The way that the workstations are connected to the network through the actual cables that transmit data -- the physical structure of the network -- is called the physical topology. The logical topology, in contrast, is the way that the signals act on the network media, or the way that the data passes through the network from one device to the next without regard to the physical interconnection of the devices.
Logical topologies are bound to the network protocols that direct how the data moves across a network. The Ethernet protocol is a common logical bus topology protocol. LocalTalk is a common logical bus or star topology protocol. IBM's Token Ring is a common logical ring topology protocol.

     Types of Network Topologies

Bus Topology: In this type of network topology, all
     the nodes of a network are connected to a common transmission medium having two endpoints. All the data that travels over the network is transmitted through a common transmission medium known as
     the bus or the backbone of the network. When the transmission medium has exactly two endpoints, the network topology is known by the name, 'linear bus topology'. In case the transmission medium, also
     called the network backbone, has more than two endpoints, the network is said to have a distributed
     bus topology. Bus topology is easy to handle and implement and is best suited for small networks. But the downside of this topology is that the limited cable length limits the number of stations, thus limiting the performance to a less number of nodes.

Ring Topology: In a ring topology, every node in the network is connected to two other nodes and the first and the last nodes are connected to each other. The data that are transmitted over the network pass through each of the nodes in the ring until they reach the destination node. In a ring network, the data and the signals that pass over the network travel in a single direction. The dual ring topology varies in having two connections between each of the network nodes. The data flow along two directions in the two rings formed thereby. The ring topology does not require a central server to manage connectivity between the nodes and facilitates an orderly network operation. But, the failure of a single station in the network can render the entire network inoperable. Changes and moves in the stations forming the network affect the network operation.

Mesh Topology: In a full mesh network, each network node is connected to every other node in the network. Due to this arrangement of nodes, it becomes possible for a simultaneous transmission of signals from one node to several other nodes. In a partially connected mesh network, only some of the network nodes are connected to more than one node. This is beneficial over a fully connected mesh in terms of redundancy caused by the point-to-point links between all the nodes. The nodes of a mesh network require possessing some kind of routing logic so that the signals and the data traveling over the network take the shortest path during each of the transmissions.

Star Topology: In this type of network topology, each node of the network is connected to a central node, which is known as a hub. The data that is transmitted between the network nodes passes across the central hub. A distributed star is formed by the interconnection of two or more individual star networks. The centralized nature of a star network provides a certain amount of simplicity while also achieving isolation of each device in the network. However, the disadvantage of a star topology is that the network transmission is largely dependent on the central hub. The failure of the central hub results renders the entire network inoperable.

Tree Topology: It is also known as a hierarchical topology and has a central root node that is connected to one or more nodes of a lower hierarchy. In a symmetrical hierarchy, each node in the network has a specific fixed number of nodes connected to those at a lower level.

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Wired vs. Wireless

Wired networks offer many advantages over wireless networks, especially in terms of speed and cost, although if your home or business isn't pre-wired with Ethernet cabling it can often end up being quite expensive to add new wiring.  Wired networks also offer security advantages over wireless networks, but most of the security risks of wireless networks can be mitigated with advanced encryption and other wireless security options.   The main advantage to deploying a wireless network, on the other hand, is simply the lack of needing any wiring at all.
In most cases, a combination of both wired and wireless network connections will serve you best, especially if your facility is already wired.  Assuming you'll be deploying either a wireless-only network or a network that combines wired and wireless technologies, let's take a look at the type of wireless network that will best suit your needs.