In this paper, we address platforms developed to provide and configure virtual networks according to user's request and needs. User requests are, however, not always accurate and can contain a number of inconsistencies. The requests need to be thoroughly analyzed and verified before being applied to such platforms. We consequently identify some important properties for the verification and classify them into three groups: a) functional or logic issues, b) resource allocation/dependency issues, and c) security issues. For each group, we propose an effective way to check the request consistency. The issues of the first group are checked with the use of scalable Boolean matrix operations. The properties of the second group can be verified through the use of an appropriate system of logic implications. When checking the issues of the third group, the corresponding string analysis can be utilized. All the techniques discussed in the paper are followed by a number of illustrating examples