The Juniper Networks Secure Services Gateway 500 Series (SSG) represents a new class of purpose-built security appliance that delivers a perfect mix of high performance, security and LAN / WAN connectivity for regional and branch office deployments. With proven network and application level protection, the SSG 520 can be implemented as standalone security devices to stop worms, Spyware, Trojans, malware and other emerging attacks. In addition, the SSG 500 Series combines security and LAN routing functionality from the market leading firewall appliances running ScreenOS with best-in-class routing hardware and WAN protocols from the Juniper Networks J-series routers and JUNOS. The result is a high performance security platform that can be deployed as a combination firewall and routing device for those customers who wish to consolidate routing and security devices and reduce IT expenses.The SSG 520 Base Memory System features 0 PIM Cards, AC Power.