Tuesday, September 1, 2009

...MESH TOPOLOGY AND TREE TOPOLOGY...


MESH TOPOLOGY

Mesh Network is a network where all the nodes are connected to each other and is a complete network. In a Mesh Network every node is connected to other nodes on the network through hops. Some are connected through single hops and some may be connected with more than one hope.

While the data is traveling on the Mesh Network it is automatically configured to reach the destination by taking the shortest route which means the least number of hops. Data travels by hopping from one node to another and then reaches the destination node in a Mesh Topology Network.

An example of a Mesh Network is the Mobile Adhoc Network or MANet. The entire Mesh Network is continuously connected. Being completely connected does not mean that Mesh Network is dependant on each and every node of the network. Even if one node fails in the Mesh Network the network finds an alternate route to transfer the data. It is called the self healing technology where it receives data one way or the other.

The Mesh Network is based on a very sensible concept and has lesser chances of a network breakdown. There are so many possible combinations of routes and hops a data transfer can take that it will reach the destination one way or the other. It is highly unlikely that all the nodes in a single Mesh Network will break down at any given point of time.

Wireless Mesh Networks

Wireless Mesh Networks work based on the radio frequencies and was originally developed by the army to be able to communicate. The reliability factor is high in any kind of Mesh Network. There are three types of wireless Mesh Topologies.

• Fixed Wireless Connections
Peer to Peer or Adhoc Networks
• Node to Node

Fixed Mesh Networks

The fixed Mesh Networks will work only in the specified location and they are not mobile networks. They are meant to be used in a limited surrounding with boundaries. The location of nodes in affixed Mesh Network is all pre determined and they are not interchangeable.

The fixed Mesh Network does not work on line of sight like the other types of Mesh Networks. The total number of hops in a fixed Mesh Network is usually fixed and also short. There may not be many nodes as this kind of Mesh Networks exist within an office or building. More often than not the data travels ion a specific direction.

Peer to Peer Mobile Networks

In a peer to peer mobile network the individual devices connect to each other using the Mesh Network. The peer does not require connecting to the main node and they can still communicate from one device to another device by taking the shortest possible data transfer route. However many experts believe that in the peer to peer Mesh Networks the problems with scalability in terms of time taken for data transfer is questionable. The device has to know to transmit the dat

a in the most optimal path and the entire data transfer or depends on this single factor. If the device is incapable then the whole purpose of using it in a peer to peer connection is lost.

Node-To-Node Network

A Node-To-Node network is a combination of fixed Mesh Network and the mobile Mesh Network. In the node to node network a network cloud is introduced and all the nodes are configured to use the network cloud to connect to each other. So this feature makes it mobile and also the network is fixed because all the nodes of the same network connect to one single network cloud.


TREE TOPOLOGY

Tree topology is a combination of the bus and the star topology. The

tree like structure allows you to have many servers on the network and you can branch out the network in many ways. This is particularly helpful for colleges, universities and schools so that each of the branches can identify the relevant systems in their own network and yet connect to the big network in some way.

A tree structure suits best when the networks is widely spread and vastly divide into many branches. Like any others topologies, the tree topology has its advantages and disadvantages, A tree network may not suit small networks and it may be a waste of cable to use it for small networks. Tree topology has some limitations and the configuration should suit those limitations.

The tree topology follows a hierarchical pattern where each level is connected to the next higher level in a symmetrical pattern. each level in the hierarchy follows a certain pattern in connecting the nodes. Like the top most level might have only one node or two nodes and the following level in the hierarchy might have few more nodes which work on the point connectivity and the third level also has asymmetrical node to node pattern and each of these levels are connected to the root level in the hierarchy. Think of the tree that branches out in various directions and all these branches need the roots and the tree trunk to survive. A tree structured networks is very similar to this and that is why it is called the tree topology.

No comments:

Post a Comment