The advanced security features like App-ID, User-ID, Content-ID along with Security profiles, comprising feature like Antivirus, Anti-Spyware, Vulnerability protection, URL Filtering, DoS Protection and Data Filtering makes Palo Alto the leader. Most importantly its malware analysis solution WildFire offers advanced protection from unknown threats.
Palo Alto Networks also offers Virtual Firewalls that are ideal for protecting virtual data centres and "East-West" traffic. With the advent of Software Defined Networking and the growing popularity of VMWare NSX, Palo Alto is offering a dedicated Virtualized Firewall VM-1000-HV. The Palo Alto VM-1000-HV was specifically developed to support VMWare NSX setups along with VMWare ESXI, Citrix Netscaler SDX , KVM and Amazon Web Services (AWS) platforms.
PA-200 and PA-500 Series Firewalls are meant for Small Businesses and come with very limited throughput and do not support Virtual Systems. Virtual Systems, also known as VSYS, is used to create virtual firewall instances in a single-pair of Palo Alto Firewalls, in other words, Virtual Systems can be compared to contexts in Cisco ASA Firewalls or vdom in Fortinet firewalls. The PA-200, PA-500 Series Firewalls offer a very limited number of security policies like security rules, NAT rules, policy based forwarding rules
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