Retransmission Steganography Applied

TL;DR

This paper experimentally evaluates RSTEG, a network steganography technique that embeds hidden data in retransmitted packets, focusing on its bandwidth and detectability in TCP networks.

Contribution

It demonstrates the practical implementation of RSTEG on TCP and assesses its steganographic bandwidth and detectability through experimental analysis.

Findings

RSTEG can embed hidden data in TCP retransmissions.

The method's detectability depends on retransmission levels.

Experimental results show measurable steganographic bandwidth.

Abstract

This paper presents experimental results of the implementation of network steganography method called RSTEG (Retransmission Steganography). The main idea of RSTEG is to not acknowledge a successfully received packet to intentionally invoke retransmission. The retransmitted packet carries a steganogram instead of user data in the payload field. RSTEG can be applied to many network protocols that utilize retransmissions. We present experimental results for RSTEG applied to TCP (Transmission Control Protocol) as TCP is the most popular network protocol which ensures reliable data transfer. The main aim of the performed experiments was to estimate RSTEG steganographic bandwidth and detectability by observing its influence on the network retransmission level.