Network management refers to the actions, techniques, proceedings, and tools that are related to the process, governance, upholding, and stipulating of networked systems. Network management is vital to rule and manage practices and is normally conceded out of a network operations axis. Governance deals with observing the path of resources in the network and how they are allocated. It includes all the maintenance that is needed to keep the network under control. This paper presents a survey of various techniques used in network management and Hidden Markov Model (HMM) that is utilized for IT service management in detail.