AUTHENTICATION: A process that proves that good data traffic truly came from where it says it originated by verifying the sending and receiving users and computers.

DMZ: A firewall configuration for securing local area networks (LANs).

EAP: (Extensible Authentication Protocol) A standard that allows two devices to authenticate.

ENCRYPTION: A method of securing messages by scrambling and encoding each packet as it is sent across an unsecured medium, such as the Internet.

FIREWALL: A part of a computer system or network that is designed to block unauthorized access.

HTTPS: (Hypertext Transfer Protocol Secure) A communications protocol for secure communication over a computer network, with especially wide deployment on the Internet.

ICS: Industrial Control System.

LAYER 2 SWITCH: A device that filters and forwards frames based on the MAC addresses of the sending and receiving machines.

LAYER 3 SWITCH: Filters data packets based on the IP addresses of sending and receiving machines.

NAT: (Network Address Translation or Network Address Translator) The translation of an Internet Protocol (IP) address used within one network to a different IP address known within another network.

PACKETGUARD: Deep packet inspection of industrial communications protocol packets (such as Modbus TCP) to identify and block potentially unsafe packets.

RADIUS: (Remote Authentication Dial-In User Service) A networking protocol that provides centralized Authentication, Authorization, and Accounting (AAA) management for users that connect and use a network service.

ROUTER: A device that forwards data packets to the appropriate parts of a computer network.

REMOTE ACCESS: The capability to access a computer or device from outside a building in which it is housed.

VPN: A network that is constructed by using public wires — usually the Internet — to connect to a private network.

VPN TUNNEL: Secure (usually encrypted) connections between two points in an insecure network environment.

SSH: (Secure Shell) A cryptographic network protocol for secure data communication, remote command-line login, remote command execution, and other secure network services between two networked computers.

SNMP: (Simple Network Management Protocol) An Internet-standard protocol for managing devices on IP networks.

Source: Moxa, a solutions provider for industrial networking, computing, and automation (