1 Introduction  
2 Related Computing Paradigms  
3 Challenges in Fog Computing  
4 Taxonomy  
5 Fog Nodes Configuration  
6 Nodal Collaboration  
7 Resource/Service Provisioning Metrics  
8 Service Level Objectives  
9 Applicable Network System  
10 Security Concern  
11 Gap Analysis and Future Directions  
12 Summary and Conclusions