The Cisco SA 500 Series Security Appliances provide an all-in-one security solution for small businesses with firewall, VPN, and optional email and web security capabilities. The appliances support evolving business needs, control access to resources, and increase employee productivity while improving business resiliency. The appliances are part of Cisco's Small Business Pro Series and include the Cisco SA 520, SA 520W, and SA 540 models, which vary in performance, connections, ports, and included security features.