In wireless sensor network (WSN) [1], energy efficiency is one of the very important issues. Protocols in WSNs are broadly classified as Hierarchical, Flat and Location Based routing protocols. Hierarchical routing is used to perform efficient routing in WSN. Here we concentrate on Hierarchical Routing protocols, different types of Hierarchical routing protocols, and PEGASIS (Power-Efficient Gathering in Sensor Information Systems) [2, 3] based routing protocols like PDCH (PEGASIS with Double Cluster Head) [4] protocol which makes every nodes load balance and extend the network lifetime. EEPB (Energy-Efficient PEGASIS-Based protocol) [5] which is a chain-based protocol to adopt a threshold when constructing chain to decrease the formation of long link to select the leader. This paper presents the hierarchical routing protocol PEGASIS and a comparative study on various versions of PEGASIS protocols.

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Wsn Pegasis Pdch Eepb Ieepb Mh-pegasis Routing Protocols