  Robustness is an important property of complex networks. Up to now, there are
plentiful researches focusing on the network's robustness containing error and
attack tolerance of network's connectivity and the shortest path. In this
paper, the error and attack tolerance of network's community structure are
studies through randomly and purposely disturbing interaction of networks. Two
purposely perturbation methods are designed, that one methods is based on
cluster coefficient and the other is attacking triangle. Dissimilarity function
D is used to quantify the changes of community structure and modularity Q is
used to quantify the significance of community structure. The numerical results
show that after perturbation, network's community structure is damaged to be
more unclear. It is also discovered that purposely attacking damages more to
the community structure than randomly attacking.
