A.G. Krylov1, G.V. Nikitin2, A.V. Peredri3, K.V. Semenov4

1–4 Military Space Academy n.a. A.F. Mozhaisky (St. Petersburg, Russia)
1–4 vka@mil.ru

The continuous and dynamic development of satellite communication systems actualizes the issues of the efficiency of using the frequency and channel resource of communication channels. In the conditions of using packet types of transmissions, fragmentation of user data packets is one of the ways to increase the efficiency of using a channel resource. A wide variety of approaches to the formation of the channel layer and their functional ambiguity in the conditions of fragmentation increase the level of uncertainty in the choice of the protocol stack used to build a communication channel, which in turn creates a prerequisite for a decrease in the quality of the use of the channel resource. In view of this, the task of modeling the procedure for forming frames of fragmented user data packets is relevant, taking into account possible variants of non-standardized protocol block headers at the channel level.

Based on the studied non-standardized headers of channel-level protocol blocks, reflecting the features of their formation, to present a model for the formation of frames of fragmented user data packets. This will make it possible to identify the necessary set of informative features, the study of which will make it possible to efficiently and with high probability recognize frames of fragmented packets in a digital data stream with packet switching in channels of satellite communication networks for various purposes.

The article considers the procedure for forming frames of fragmented user data packets with non-standardized headers of protocol blocks at the channel level used in data transmission channels with packet switching of satellite communication systems for various purposes. The structural and structural-linguistic models of frames of a fragmented package of user data in conditions of transmission over a satellite communication channel have been developed. The structure of signals with fragmented packets of user data based on a directed graph is presented and investigated. The service level indicators of the fragmented user data package frame formation model were evaluated according to parameters that allow an objective assessment of the effectiveness and validity of the use of fragmentation in data transmission in satellite communication channels.

The data obtained using the developed model allows us to qualitatively assess the indicators of the level of service of the data transmission channel with fragmentation of user message packets and reasonably prove the effectiveness of the fragmentation described by the model when it is necessary to split the desired message into parts when it is transmitted over the CCC channel.

Krylov A.G., Nikitin G.V., Peredriy A.V., Semenov K.V. A model for the formation of frames of fragmented user data packets with non-standardized protocol block headers at the channel level. Dynamics of complex systems. 2024. V. 18. № 2. P. 11−27. DOI: 10.18127/j19997493-202402-02 (in Russian).

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