The Cisco ASA 5520 Adaptive Security Appliance delivers security services with Active/Active high availability and Gigabit Ethernet connectivity for medium-sized enterprise networks in a modular, high-performance appliance. With four Gigabit Ethernet interfaces and support for up to 100 VLANs, businesses can easily deploy the Cisco ASA 5520 into multiple zones within their network. The Cisco ASA 5520 Adaptive Security Appliance scales with businesses as their network security requirements grow, delivering solid investment protection. Businesses can extend their SSL and IPsec VPN capacity to support a larger number of mobile workers, remote sites, and business partners. Businesses can scale up to 750 SSL VPN peers on each Cisco ASA 5520 by installing an SSL VPN upgrade license; 750 IPsec VPN peers are supported on the base platform. VPN capacity and resiliency can be increased by taking advantage of the Cisco ASA 5520's integrated VPN clustering and load-balancing capabilities. The Cisco ASA 5520 supports up to 10 appliances in a cluster, offering a maximum of 7500 SSL VPN peers or 7500 IPsec VPN peers per cluster. For business continuity and event planning, the Cisco ASA 5520 can also benefit from the Cisco VPN FLEX licenses, which enable administrators to react to or plan for short-term bursts of concurrent SSL VPN remote-access users, for up to a 2-month period. The advanced application-layer security and content security defenses provided by the Cisco ASA 5520 can be extended by deploying the high-performance intrusion prevention and worm mitigation capabilities of the AIP SSM, or the comprehensive malware protection of the CSC SSM. Using the optional security context capabilities of the Cisco ASA 5520 Adaptive Security Appliance, businesses can deploy up to 20 virtual firewalls within an appliance to enable compartmentalized control of security policies on a departmental level. This virtualization strengthens security and reduces overall management and support costs while consolidating multiple security devices into a single appliance.