This chapter highlighted some of the more important issues involved in performance-tuning your perimeter security. Performance and security often seem at odds with each other, but careful design can help minimize the impact that security has on performance. Remember that almost any security feature you want to implement will come with varying levels of performance impacts. You should be especially careful when implementing encryption in your design. Cryptographic techniques offer tremendous security advantages, but they are expensive from a performance standpoint. Try to identify as early as possible the performance requirements of your network, prior to building or revising your network structure. Performing this initial analysis will help you choose appropriate security measures that permit the security policy to be enforced while still allowing the network users sufficient performance to carry out their work efficiently. Security and performance must be in balance for the ultimate objectives of the network to be met.