Since the invention of the connectors that serve as one of the building blocks of software architecture, various researchers have described the characteristics of connectors that they have discovered in given software systems. These characteristics have frequently been revealed by employing a bottom-up approach to different disciplines of software engineering. As a consequence, numerous attributes of connectors have been introduced at a rather technical level, and the vocabulary regarding specific aspects of connectors is highly heterogeneous. This eclectic list of attributes is not an appropriate abstraction level for an architect when developing connectors for application software. Instead, it would be more helpful to have a framework that begins from a conceptual perspective and guides the software architect in identifying the attributes required for a specific connector. To this end, a hierarchical schema for specifying software connectors is proposed in this paper. In contrast to existing schemas in which either the attributes considered are few in number and ungrouped or the attribute specification and grouping was not the main focus of the research, this paper presents a homogenous specification schema at different levels of abstraction and is based on logical perspectives rather than technical features. The schema can support architects in various situations-such as connector selection and documentation-and can aid in implementing or generating concrete software connectors. The application of the schema will be demonstrated by specifying a software connector between Twitter and an application.