Network security is the protection of the underlying networking infrastructure (1) access, misuse, or theft. It involves creating a secure infrastructure for device and applications to work in a (2) manner.
Network security combines multiple defenses at the edge and in the network. Each network security layer implements（3）controls.Authorized users gain access to network resources. A(4) is a network device that monitors incoming and outgoing network traffic and decides whether block specific traffic based on a defined set of security rules. A virtual （5）encrypts the connection from an endpoint to a network,often over the internet, remote-access VPN uses IP see or Secure Sockets Layer to authenticate the between device and network.