Packet validation using watermarks

摘要

Methods and systems are disclosed for providing secure transmissions across a network comprising a transmitting device and a receiving device. At the transmitting device, a stream of watermark bits is generated. Next, a plurality of watermarks is generated, each of the plurality of watermarks comprising an index number and a portion of the stream of watermark bits. The watermarks are inserted, into each header of a plurality of outgoing packets. At the receiving device, the plurality of outgoing packets are received and it is determined if a received packet is valid based on the watermark in the header of the received packet. The stream of watermark bits may be generated using a stream cipher such as RC4, a block cipher such as 3DES in CBC mode, or other equivalent pseudo-random stream generating techniques.

主权项

1. A method for secure transmissions between a client device and a server, comprising:
receiving, at the server, a packet from the client device, wherein the packet includes a watermark comprising a portion of a stream of watermark bits and an index number associated with the portion of the stream of watermark bits, and the stream of watermark bits generated from an authorization and synchronization packet previously exchanged between the client and the server; and determining whether the received packet is valid based on the watermark of the received packet, wherein said determining comprises comparing the watermark to a set of expected watermarks in a first window and a set of expected watermarks in a second window, the set of expected watermarks in the first window generated from the stream of watermark bits based on index numbers preceding a pivotal index number, and the set of expected watermarks in the second window generated from the stream of watermark bits based on index numbers succeeding the pivotal index number.