Network coding and decoding method and device based on cyclic shift and related components

Abstract

The invention discloses a network coding and decoding method and device based on cyclic shift and related components, and the method comprises the steps: constructing a basis matrix based on a (n, k) parameter and a preset coding criterion; performing cyclic shift construction on the basis matrix to obtain a shift matrix; obtaining original data, and dividing the original data into k source packets; taking the k source packets as system packets, and performing m times of shifting and coding on the k source packets according to the shifting matrix to obtain m verification packets; combining the system packet and the verification packet to obtain n coding packets, n = k + m; wherein the decoding process comprises the following steps: randomly selecting k coding packets from n coding packets, then searching a coding packet with an exposed bit from the k coding packets, obtaining the exposed bit, substituting the exposed bit back into other coding packets, and then eliminating the exposed bit according to a preset operation method, and repeating the operations similarly until all the exposed bits in the k coding packets are eliminated. According to the invention, the coding and decoding overhead can be effectively reduced through increment difference and cyclic shift.

Description

technical field [0001] The present invention relates to the technical field of computer software, in particular to a cyclic shift-based network encoding and decoding method, device and related components. Background technique [0002] The core idea of ​​a distributed system is to obtain (n, k) combination properties (CombinationProperty, CP) through encoding, that is, to encode k original independent tasks into n (n≥k), among the n task results, any K can restore the original k storage or calculation results. Shift-and-Add coding (Shift-and-Add, SA) only includes shift and addition operations, which avoids a large number of multiplication operations in the linear coding stage and reduces computational complexity. Corresponding to SA is Zigzag Decoding (ZD). ZD can avoid a large number of complex operations such as multiplication and division, and only needs a simple back-substitution algorithm, which greatly reduces the computational burden. In addition, a code that has bo...

AI Technical Summary

Problems solved by technology

But this encoding still has some shortcomings. Inc-Diff encoding is asymmetric and when n and k are relatively close, its storage overhead is relatively large, and its storage overhead is m(k-1), where m=n-k

[0004] 2. In 2017, a coding scheme of ZD nature with a small overhead - cyclic shift permutation matrix coding was proposed, and this coding is called Cyc-Shift. This code has low coding and decoding complexity, and its storage overhead is relatively low. Inc-Dif should be small, for However, this code can only be applied to scenarios where n≤2k, and is not general

The Base-Shift code can be applied to any (n, k) scene, however, when the ratio of m / k is larger, the overhead of this code is also very large, which still brings a great burden to the communication cost

[0006] The disadvantage of the existing CP-ZD code is that the overall overhead is relatively large. When the coded packet m is larger, the overhead increases faster, and the communication cost is high, which is not suitable for the application of large-scale distributed systems.

Images