This paper provides an extensive survey of the different methods of addressing security issues in the grid computing environment, and specifically contributes to the research environment by developing a comprehensive framework for classification of these research endeavors. The framework presented classifies security literature into System Solutions, Behavioral Solutions, Hybrid Solutions and Related Technologies. Each one of these categories is explained in detail in the paper to provide insight as to their unique methods of accomplishing grid security, the types of grid and security situations they apply best to, and the pros and cons for each type of solution. Further, several areas of research were identified in the course of the literature survey where more study is warranted. These avenues for future research are also discussed in this paper. Several types of grid systems exist currently, and the security needs and solutions to address those needs for each type vary as much as the types of systems themselves. This research framework will aid in future research efforts to define, analyze, and address grid security problems for the many varied types of grid setups, as well as the many security situations that each grid may face.