Abstract
For reduction of gateway bottleneck effect, data access cost, and response delay, many cooperative caching schemes are available. But in all the existing schemes, whenever any data is newly cached or any data is evicted, the information needs to be broadcast to all the mesh access points (MAPs). As a result, communication cost increases. In this chapter, a cluster and sub-cluster-based cooperative caching scheme is designed to minimize the communication cost. Clusters and sub-clusters are formed by taking advantage of the static position of Mesh routers. Cluster-heads (CHs) are selected using minimum spanning tree and minimum weighted vertex cover algorithm. Then the clusters and sub-clusters are formed. CHs and other Maps keep different cache information tables, and based on those, cache decision is taken. Client mobility is also considered. The performance of the proposed scheme and some other existing schemes have been compared. It has been observed that in the proposed scheme, communication cost in terms of number of messages is reduced.
TopThis section discusses some of the existing schemes.
Key Terms in this Chapter
Mesh Router: Mesh routers are the nodes which perform the routing activities in the WMN.
Wireless Mesh Network: Wireless mesh network is a self-healing and self-organizing wireless network where the mesh nodes can communicate to each other through multiple path.
Mesh Access Point: These are the mesh nodes having access point capability. It can serve the clients as an access point forming a basic service set. At the same time, it can communicates with the WMN. By these nodes, clients can send and receive data packets to and from other nodes.
Cooperative Caching: Cooperative caching is the process of sharing and coordination of data among the nodes without going to the data source.
Mesh Client: Mesh clients are the mobile or static devices which are using the services of WMN.
Cluster Head: Cluster heads are the nodes which act as a leader of a cluster. Different techniques are used to form the cluster and to select the cluster head.
Gateway: Gateways are the nodes which connect the WMN to the external network. All the traffic to and from the external network goes through the gateway.
Mobile Host: These are the nodes which coordinate to cache the data.