There is an overwhelming dependence on Global Positioning System (GPS) in every sector, ranging from civil to military. The over dependence on GPS and its potential vulnerabilities has raised many concerns among government, scientists and all those who employ GPS for their business and other critical applications. It is due to the fact that GPS receivers can be easily be spoofed and the operations of any system can be disturbed and compromised which may result in a catastrophe. Many techniques have been proposed to meet the challenge of protecting GPS receivers from spoofing threat but none of these techniques are in use. Researchers are trying desperately to find a complete solution to meet this threat. This paper will present an analytical overview of the techniques that have been proposed to protect civilian GPS receiver. This survey analyzes different alternative solutions to prevent spoofing and explore a combination of two or more techniques that can provide most effective spoofing countermeasure technique.