## 7 Protocol Comparisons
### Architecture Comparison  
[PERSON] _et al_. presented in [35] a methodology for routing and topology information maintenance in mobile wireless network based on the existence of clusters in random graphs. They divided the graph into a number of overlapping clusters. There are no cluster heads in the proposal. It is an on-demand source routing. The performance of the routing protocol proposed by them is determined by the average cluster size. The effectiveness of their approach lies in the fact that any routing protocol can be directly applied to the network, replacing the nodes by clusters. They designed nine messages, but their approach has to be implemented over another routing protocol. They proposed a standard distance vector routing protocol to apply their proposal. Taking into account that AODV has seven messages. Their implementation needs 16 messages. CBRP (cluster-based Routing protocol) was proposed in [6]. The protocol divides the nodes of the _ad hoc_ network into a number of overlapping or disjoint 2-hop-diameter clusters in a distributed manner. CBRP uses IP Protocol for routing purposes and interoperability with fixed networks. It uses six messages plus the ARP messages, so it needs eight messages to work properly. As a source routing protocol, there is an overhead of bytes per packet. In [36], the authors proposed a Cluster-Based Security Architecture for _ad hoc_ networks. They proposed a division of the network into clusters, with one special head node each, for a distributed public key infrastructure. These cluster head nodes execute administrative functions and hold shares of a network key used for certification. KCLS protocol was proposed in [37]. The paper describes a location-service protocol based on the clustering architecture, which is able to balance the tradeoff between the communication overheads and the accuracy of location information. It has the capability of cluster-level self-route recovery against interlink failures. Taking into account that KCLS is based on the KCMBC protocol and on a Link State protocol, it needs 13 messages plus the protocol needed to acquire their position using GPS. In [9] the authors proposed an adaptive clustering scheme for spatial reuse of the bandwidth (relying on a code division access scheme) for multimedia support in Mobile Wireless Networks. They use only one code within each cluster. The clusters are independently controlled and are dynamically reconFigured as nodes move. Bandwidth can be shared or reserved in a controlled fashion in each cluster. LEACH (Low-Energy Adaptive Clustering Hierarchy) protocol was proposed in [34]. It is a clustering-based protocol that utilizes randomized rotation of local cluster-heads minimizing the global energy usage by evenly distributing the energy load among the sensors in the network. LEACH uses localized coordination and incorporates data fusion into the routing protocol to reduce the amount of information that must be transmitted to the base station. It is completely distributed, requiring no control information from the base station, and the nodes do not require knowledge of the global network in order to operate. Reference [38] presented the \"Base Station Controlled Dynamic Clustering Protocol\" (BCDCP). Their proposal utilizes a high-energy base station to set up clusters and routing paths, perform randomized rotation of cluster heads to avoid cluster head overload, and carry out other energy-intensive tasks. It distributes the energy dissipation evenly among all sensor nodes to improve network lifetime and average energy savings. In [39], authors proposed CLACR (Core Location-Aided Cluster-Based Routing Protocol for Mobile _Ad Hoc_ Networks). CLACR splits the network into square clusters. Cluster heads compute the desired route using Dijkstra algorithm, which reduces the number of nodes participating in routing, the routing traffic and the route setup time. CBLARHM (Cluster Based Location-Aware Routing Protocol for Large Scale Heterogeneous MANET) was proposed in [40].