For any communication system network latency, also called network lag, is the time it takes for a request to travel from the sender to the receiver and for the receiver to process that request. Networks with smaller communication delays are called low-latency networks. In the case of high latency networks delays are longer affecting the performance of the system. So, to have the best user experience, optimization of the network latency is very much needed. The chapter discusses the Modified dropping-random early detection (MD-RED) algorithm, Minimum transmission delay algorithm for multi-hop nodes, Hybrid Fuzzy-Genetic Algorithm, Congestion avoidance with source location privacy, multi-objective-based deployment of throw boxes, Taxonomy of controller placement problem (CPP) optimization, JOSP: Joint Optimization of Flow Path Scheduling and Virtual Network Function Placement, etc. The chapter also reviews the optimization methods for unstructured, scalable, and 6G networks. In addition, the chapter also analyses some protocols related to WSN viz., energy efficient routing protocols with optimization, Asynchronous Anycast Cross-layer Protocol, Cross-Layer Protocol, and Data Fusion and Cluster-Based Multi-hop Relay-Assisted Routing Protocol.