Concerns Related to Tunneling Through or Across a Firewall

Hacker tunneling that can be accomplished through or across your firewall deployments are a serious threat to your organization’s network security. Tunneling is the creation of a communication channel similar to the creation of a VPN. In some cases, it uses actual VPN solutions and protocols. Tunneling can create either a covert channel or a known channel that is unfiltered.

Tunneling uses two techniques. One method is to install a server component on an internal system, and then an external client component initiates the connection. This technique requires the firewall to allow inbound initiation connections to internal systems. A second method is to install a server component on ...

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