Discussion on AdHoc wireless network routing protocol (1)

When we analyzed the AdHoc wireless network, we found that its routing protocol is very important. If its routing is under attack, the entire network would not work normally. Therefore, it is necessary to analyze and discuss its routing protocol in depth.

AdHoc wireless network routing protocol design requirements

A key issue in AdHoc Network Design is the development of a routing protocol that can provide high-quality and efficient communication between two nodes. The mobility of network nodes makes the network topology constantly changing, traditional Internet-based routing protocols cannot adapt to these features. Therefore, a dedicated routing protocol is required for AdHoc networks. According to the previous description of the structure and characteristics of AdHoc networks, the designed routing protocol must meet the following conditions:

(1) It is necessary to have the ability to quickly adapt to the dynamic changes of the network topology, and to avoid the occurrence of routing loops as much as possible, providing a convenient and simple network node location method ｡

(2) Use limited bandwidth resources efficiently to reduce unnecessary overhead as much as possible ｡

(3) The number of intermediate transfers for multi-hop communication is also limited. Generally, the number should not exceed 3 ｡

(4) The launch time and data volume must be minimized to save limited work energy ｡

(5) Make the designed Routing Protocol Secure and reduce the possibility of attacks as possible ｡

Analysis of AdHoc Wireless Network Routing Protocol

According to the particularity of AdHoc wireless network routing protocols, a variety of Adhoc Network Routing Protocols have been proposed in recent years. The MANET team of IETF is currently focusing on the research of AdHoc Network Routing Protocols and has proposed many protocol drafts, in addition, professional researchers have published a large number of articles on AdHoc Network Routing Protocols, and proposed many AdHoc Network Routing Protocols, such as DSDV and WRP. According to the routing trigger principle, the current routing protocols can be roughly divided into a prior routing protocol, reactive routing protocol and Hybrid Routing Protocol ｡

Predicate Routing Protocol

The predicate routing protocol is also known as the table-driven routing protocol. Each node maintains a route table containing route information arriving at the node, and updates the route table at any time based on changes in the network topology, therefore, the route table can accurately reflect the network topology. Once the source node sends a message, it can immediately obtain the route to the target node, this type of routing protocol is usually used to adapt to AdHoc wireless network requirements by modifying the existing wired routing protocol, such as the destination node sequence distance vector protocol (DSDV) obtained by modifying the routing information protocol (RIP) therefore, the delay of this routing protocol is small, but the Protocol requires a large number of routing control packet routing, the Protocol overhead is large. Common prior routing protocols include DSDV, HSR, GSR, WRP ｡

DSDV avoids the generation of routing loops by setting serial numbers for each route. It uses time-driven and event-driven technologies to control the transmission of Route tables, that is, each mobile node retains a route table locally, the information includes all valid sink points, route hops, and serial numbers of the destination route, the serial number of the destination route is used to distinguish between the new and old routes to avoid loop generation. Each node periodically transmits the local route table to the neighboring nodes, or when the route table changes, the route information is also sent to the neighboring points. When no node moves, large data packets (including multiple data units) with long intervals are used for Route updates; after the neighboring node receives information about the route table that contains the modification, it first compares the size of the serial number of the source K sink route, however, routes with a small serial number are eliminated. If they are the same, the optimal standard routing (such as the shortest path) is used )｡

HSR (HierarchicalStateRouting) is a routing protocol used for hierarchical networks. An advanced node stores the location information of all its child nodes, the logical sequence address is allocated to the node along the path from the highest-level root node to the lowest-level leaf node. You can use the sequence address for node addressing ｡

GSR is a global state routing protocol. It works in a similar way as DSDV. It uses a link state routing algorithm, but avoids the flooding of routing packets, it includes a nearby node table, network topology table, next hop route table, and distance table ｡

WRP is a distance-vector routing protocol. Each node maintains a distance table, route table, link overhead table, and message retransmission table, generate your own SST using the Shortest Path of the neighboring node, and then pass the update information to the neighboring node. When the network route table does not change, the receiving node needs to return an idle message to indicate the connection. Otherwise, the distance table is modified to find a better path. This algorithm is characteristic when any adjacent node changes, check the robustness of all adjacent nodes to eliminate the loop, with fast convergence ｡