The prosperity of the Internet has made it attractive to hackers and malicious attackers. Internet worms have become one type of major threats to the network infrastructure. Distributed defense collaborating with single-point-deployed security applications over multiple network domains are promising. However, most of the reported collaborative schemes for distributed defense are application-specific. There is not much research that studies the general properties of variant collaborative schemes systematically. In this paper explores properties of general collaborative defense strategies from the perspective of complex system. A three-layered network modeling platform has been developed. Taking advantage of small-world network model, the platform consists of two network layers and one application layer. On top of it, an experimental comparison study of collaborative defense schemes has been conducted. Their performance and effectiveness facing signature-embedded worm attacks have been evaluated.