Wireless networks are used to provide remote and mobile users with Data and Voice services. However, the current TCP will not be able to provide the same kind of reliability it provides in a terrestrial network, to a wireless network, due to asymmetries and transmission errors. It has been found that the performance of the TCP suffers terribly over wireless links. This is because of the assumption made by TCP, that drops occur in a network, only because of congestion, is no longer valid in a wireless scenario. This performance degradation, is especially pronounced in the case of satellite networks, where huge RTTs are involved. Hence there is a urgent need in today's networking community to amend this disability of TCP. In this paper we propose a Enhancement to TCP, using the Muliti-level ECN (MECN). MECN is an extension to the standard ECN, which conveys more accurate congestion feedback information to the sources to control the congestion. We use congestion feedback from MECN, to assess the level of congestion in the network and use this information to differentiate a congestion loss from a wireless transmission loss. The sources take advantage of this differentiation and act accordingly to improve the use of network resources and therefore the throughput of TCP over wireless links. Our initial simulations using the ns-2 simulato , confirms our results.

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