Patent Document ID: 9137492
Application ID: 13836981
Patent Flag: 1

Claim One:
1. A method for streaming video data in a network including a server node, a plurality of relay nodes and one or more receiver nodes and including a set of security operations and video streaming operations with network coding, the method comprising performing a one-time key distribution between the source node and each of the one or more receiver nodes; dividing the video data into one or more group of pictures (GoP), each of the more than one group of pictures having a predetermined time of duration; for each group of pictures (GoP), generating at the source node and an n×n lower-triangular matrix A, in which l is a number of layers in the GoP wherein there are n j rows in the matrix A for each layer, and n=n l l and wherein matrix A is used for encoding at the source only and each non-zero entry of matrix A is an elemental a ij chosen uniformly at random from all non-zero elements of the field F g {0}; dividing the GoP into a plurality of vectors b (1). .. b (w) , each of the vectors having n symbols b 1 -b n in which positions n l (l j −1)+1 to n l l j of each vector belongs layer l j ; encrypting m l symbols of each layer in vectors b (i) 1≦l≦w, with a stream cypher and random keys k (1) -k (j) where there is one key for each layer; applying the encoding matrix A successively to the information symbols to be sent to provide a payload of one or more packets, comprised of encoded information symbols; encrypting each n l lines of a matrix A with a corresponding layer key, wherein the first matrix A corresponds to a locked coefficients matrix; generating an n×n identity matrix corresponding to the unlocked coefficients wherein each of the packets comprise a header and the payload and wherein the header comprises the locked and unlocked coefficients; encoding the packets in relay nodes in accordance with a random linear network coding (RLNC) protocol wherein algebraic coding is performed on unlocked coefficients, locked coefficients and payload and wherein the relay nodes identify the layer of a packet by looking at the first non-zero position in the unlocked coefficients, and packets are mixed with packets of the same or lower layers only; and sending the first n l lines of matrix A unencrypted so as to make the base layer accessible to all nodes and wherein encryption of the locked coefficients then starts at row n l +1 such that layer 1 is accessible to all nodes in the network.