I. Introduction

II. Security Requirements in Wireless Networks

III. Security Vulnerabilities in Wireless Networks

IV. Security Defense Protocols and Paradigms for Wireless Networks

V. Wireless Physical-Layer Security Against Eavesdropping

VI. Wireless Jamming Attacks and Their Countermeasures

VII. Integration of Physical-Layer Security into Existing Wireless Networks

VIII. Open Challenges and Future Work

IX. Conclusions