Network function virtualization (NFV) has gained prominence in next-generation cloud computing, such as the fog-based radio access network, due to their ability to support better QoS in network service provision. However, most of the current service function chain (SFC) deployment researches do not consider the Security-Service-Level-Agreement (SSLA) in the deployment solution. Therefore, in this work, we introduce the SSLA into SFC deployment to defend attacks. Firstly, we formulate the SSLA guaranteed SFC deployment problem by using linear programming. Then, we propose the Maximal-security SFC deployment algorithm (MS) to maximize the security of the SFC deployment. However, the MS algorithm results in a high deployment cost. To reduce the deployment cost, we propose the Minimal-cost and SSLA-guaranteed SFC deployment algorithm (MCSG) to minimize the deployment while satisfying the SSLA. In order to reduce the blocking ratio caused by MCSG, the Minimal-cost and SSLA-guaranteed SFC deployment algorithm with feedback adjustment (MCSG-FA) is proposed. Finally, we evaluate our proposed algorithms through simulations. The simulation results show that the blocking ratio and the deployment cost of our algorithms are better than that of the existing algorithm when meeting the SSLAs.

由于网络功能虚拟化（NFV）在网络服务提供中支持更好的QoS的能力，因此它们在下一代云计算（例如基于雾的无线电访问网络）中得到了广泛的关注。但是，当前大多数服务功能链（SFC）部署研究都没有考虑部署解决方案中的“安全-服务级别协议”（SSLA）。因此，在这项工作中，我们将SSLA引入SFC部署中以防御攻击。首先，我们通过使用线性编程来制定SSLA保证的SFC部署问题。然后，我们提出最大安全性SFC部署算法（MS），以最大程度地提高SFC部署的安全性。然而，MS算法导致高的部署成本。为了降低部署成本，我们提出了最小成本和SSLA保证的SFC部署算法（MCSG），以在满足SSLA的同时最大程度地减少部署。为了降低由MCSG引起的阻塞率，提出了具有反馈调整的最小成本和SSLA保证的SFC部署算法（MCSG-FA）。最后，我们通过仿真评估我们提出的算法。仿真结果表明，在满足SSLA要求时，我们的算法的阻塞率和部署成本要优于现有算法。