Extensive use of computer networks is associated with the development of various effective methods that are suitable for hiding information in the contents transferred over the network. These methods are described as network steganography. Since web applications use HTTP protocol to transmit the requests to the server and send the answers to the final recipient, specifically HTTP protocol is ideal for hiding information. For example, there are several methods that can be used to transmit the additional content in the HTTP header. In this paper, we present authors’ evaluation method for network steganography using HTTP specific properties and evaluate the effectiveness of some techniques, providing experimental results.

Steganography is a technique that allows hidden transfer of data using some media such as Image, Audio, Video, Network Protocol or a Document, without its existence getting noticed. Over the past few years, a lot of research has been done in the field of Image, Video and Audio Steganography but very little work has been done in Network Steganography. A Network Steganography technique hides data in a Network Data Unit, i.e., a Network Protocol Packet. In this paper we present an algorithm ARPNetSteg that implements Network Steganography using the Address resolution protocol. Our technique is a robust technique that can transfer 44 bits of covert data per ARP reply packet.