The TCP performance across the MANETS is reduced because of several factors that are discussed below and these take the complete responsibility of degrading the performance of TCP throughout the MANETs.

  • Bit Error Rates: The estimation of performance of TCP over the Mobile Adhoc Networks is always based on the High Bit Error Rates. Generally, “High Bit Error Rates” are caused commonly in wireless routes because of the inner issues like multipath fading and degradation of signal and therefore at last leads to TCP data segment loses and packet loses. The entire performance of the system gets affected so much by the congestion control mechanism that is invoked unnecessarily by the TCP.
  • Route Failures: Due to the mobility nature of the MANETs, there are several chances for the failures in the routes and therefore the TCP performance is affected by these frequent route failures. Generally, the routing protocol that is utilized throughout the MANET is responsible for the time taken by the MANET for the re-establishment of route and it may take more time in some situations and thus a congestion control mechanism is invoked by the TCP which is in a state of congestion and thus the performance of the system on the whole is affected a lot.
  • Multipath routing: Multipath routing is one among the most significant factors that degrades the performance of TCP over the MANETs and this is considered as the natural behavior of MANETs. Generally in MANETS several routes are maintained between the source and the destination and therefore the situation of packets out of sequence is observed near the receiver. The generation of duplicate ACKs throughout the network is caused because of this situation and this same to the situation of congestion in TCP and therefore the congestion control mechanism is invoked by TCP in order to decrease the duplications and thus the performance of the entire system is affected.

This paper is written and submitted by Sujana Priya V.