An essential matter for ad hoc networks is routing protocol design which is a major technical challenge due to the mobility of the nodes. Routing problem becomes more complex and challengeable and it probably is the most addressed and studied problem in ad hoc networks. There are several classifications of routing protocols are used to perform routing the information from source to destination. Classification methods help them and designers to understand distinct characteristics of a routing protocol and find its relationship with others. This paper is to explore and to compare the concept of all routing protocol based on update mechanism.