Mathematics

Computer science

Network packet

Fountain code

Set (abstract data type)

Decoding methods

Transmission (telecommunications)

Telecommunications

Algorithm

Block code

Code (set theory)

Concatenated error correction code

Online codes

Luby transform code

Mathematical analysis

Erasure code

Programming language

Upper and lower bounds

Computer network

IEEE Transactions on Information Theory

Live communication is ubiquitous, and frequently must contend with reliability issues due to packet loss during transmission. The effect of packet losses can be alleviated by using erasure codes, which aid in recovering lost packets. Streaming codes are a class of codes designed for the live communication setting, which encode a stream of message packets arriving sequentially for transmission over a packet-loss channel. The existing study of streaming codes considers settings where the sizes of the message packets to be transmitted are all fixed. However, message packets occur with unpredictable and variable sizes in many applications, such as videoconferencing. In this paper, we present a generalized model for streaming codes that incorporates message packets of variable sizes. We show that the variability in the sizes of message packets induces a new trade-off between the rate and the decoding delay under lossless transmission. Moreover, the variability in the sizes of message packets impacts the optimal ra...

Streaming Codes for Variable-Size Messages