Techniques for adaptively and selectively protecting control plane of communications network

A method is described that includes receiving at a network element a transmission control protocol ("TCP") packet with TCP options set on a link between a controller and a destination node. If the network element comprises a transit node, the method includes comparing a bandwidth value indicated in a TCP options field of the received TCP packet with an outgoing link bandwidth of the network element. If the bandwidth value indicated in the TCP options field is greater than the outgoing link bandwidth of the network element, the method includes updating the bandwidth value in the TCP options field to be equal to the outgoing link bandwidth of the network element, and forwarding the packet to a next network element. If the bandwidth value indicated in the TCP options field is not greater than the outgoing link bandwidth, the bandwidth value in the TCP options field is not changed.