The merchandise is described in your letter as a Network Gateway Security Device. The actual name of the product is “Symantec Firewall/Virtual Private Network (VPN) Appliance.” This device is a fully integrated computer firewall and rack mountable unit which monitors network traffic to protect the network against several security threats through a combination of firewall, anti-virus, Internet content filtering, intrusion detection and virtual private technologies. Small offices can create a high-speed Local Area Network (LAN) that enables secure access and interaction via the Internet between remote locations, business partners and corporate networks. One of the key points of this device is that it provides secure Internet connectivity, when reaching out to the Wide Area Network (WAN), and protects networks with integrated firewall functionality.
[1] Please importantly note that only the relevant portion of the related is displayed above. You may refer to the said customs ruling for the entire ruling explanation.
[1]. https://rulings.cbp.gov/ruling/I83651