Abstract: It has been proved that network coding can provide significant benefits to network protocols, such as increased throughput, reduced network congestion, higher reliability, and lower power consumption. Therefore, this new technology can be wildly used in traditional computer networks, wireless sensor networks and peer-to-peer systems. However, network coding is very vulnerable pollution attacks. In recent years, many schemes have been designed to prevent this attack, but most of these schemes are only suitable for single source network, and they can not satisfy the security requirements of multi-source network coding. This paper gives a depth analysis to pollution attacks in multi-source network coding, and makes a definition of secure signature for multi-source network coding, then proposes a secure and efficient signature scheme to prevent the pollution attacks in multi-source network coding. This scheme can meet all of the secure requirements in multi-source network coding.

Key words: multi-source network coding, discrete logarithm, signature scheme

摘要： 网络编码已被证明在提高网络传输速率、减少网络拥塞、增强网络可靠性以及降低结点能耗等方面有着巨大优势，因此可被广泛用于计算机网络、无线传感器网络以及p2p系统中。但是，网络编码也面临着多方面的安全威胁，其中污染攻击是其最主要的安全威胁之一。目前，绝大部分的签名方案均只能适用于对单源网络编码中的污染攻击，无法满足普遍存在的多源网络编码的安全要求。对多源网络编码中的污染攻击进行了更深入的分析，给出了安全的多源网络编码所需要满足的条件，提出了一个安全高效的多源网络编码签名算法来预防网络中的污染攻击，该算法可以满足多源网络编码的全部安全要求。

关键词: 多源网络编码, 离散对数, 签名算法