Patent ID: 7822073

Claim:
A system for embedding a covert side channel communication in an overt communication transmitted over a network using a packet stream, comprising: a. an encoder configured to encode one or more bits of a side channel communication, the encoder including: i. a packet group selection module configured to select at least two groups of related packets from the overt communication being transmitted on a network, each group of packets including a same number of packets; ii. a packet relation module configured to relate a packet of one group to a packet of another group to form a pair of packets; and iii. a packet delay module configured to delay the timing of at least one packet from each pair of packets; and b. a decoder configured to decode the bits from the side channel communication, the decoder including: i. an inter-packet delay determination module configured to determine the difference in timing between the two packets for each pair of packets; ii. a difference determination module configured to determine at least one inter-packet delay difference between two or more determined inter-packet delays; and iii. a bit extraction module configured to convert the at least one interpacket delay differences into a bit.