TCP Flags – ECN Echo ECN (Explicit Congestion Notification) ECN helps to resolve the congestion between sender & receiver. This is carried out by sending the notification i.e. echo by the receiver stating that there is congestion. This further help to send the notification of network congestion without dropping any packets. Previously this signal congestion is reported by dropping the packets. Once the receiver send the echo of the congestion, the sender will reduce the transmission rate just like it had dropped the packet. Further, ECN is supported by TCP by 3 flags in TCP Header. The first is NS (Nonce Sum) is used against the concealment whether malicious or accidental by the sender. The other two are echo and congestion-echo is received. These are called ECN-Echo & Congestion Window Reduced bits. @vitinstitute www.linkedin.com/company/vivekananda-i-t-institute/ www.facebook.com/vitinstitute 2nd Floor, Nayan Chamber, Parkar Wada, Dandia Bazar, Vadodara – 01 +91 9510911187 / 9974199876 www.vitinstitute.com