MANET is self-independent, self-organized and infrastructure less network with no fixed BS. The immediate mobile nodes between two nodes act as router to deliver the packets between them. So, MANET is a highly dynamic network. Mobile Ad-hoc NETwork (MANET) routing protocols have been divided in several different categories such as reactive and proactive routing protocol. The performances of these categories are evaluated in different scenario with TCP variants. Several different variants have been developed in order to refine congestion control in Mobile Ad-hoc NETworks (MANETs).