Cybersecurity Glossary

Topology is the geometric arrangement of a computer system. Common topologies include a bus, star, and ring. Two networks have the same topology if the connection configuration is the same, although the networks may differ in physical interconnections, distances between nodes, transmission rates, and/or signal types.

A tunnel is a communication channel that is created in a computer network by encapsulating a communication protocol’s data packets in a second protocol that normally would be carried above, or at the same layer as, the first one. Most often, a tunnel is a logical point-to-point link created by encapsulating the layer 2 protocol in a transport protocol (such as TCP), in a network or inter-network layer protocol (such as IP), or in another link layer protocol. Tunneling can move data between computers that use a protocol not supported by the network connecting them.

Token-based access control is an authentication method that offers additional security. Using this method, each user has a smart card or token that either displays a constantly changing password, passkey, or buttons that calculate a new password based on a challenge phrase. Without this card or token, it is impossible to authenticate yourself to the system. This two-factor authentication provides additional security by requiring an attacker to both guess the user’s password and steal the smart card or token that is used to access the system.

Tamper is defined as deliberately trying to change or alter a system’s logic, data, or control information to cause the system to perform unauthorized functions or services.

A threat model is a process that is used to optimize network security by identifying the key objectives and vulnerabilities, and then defining countermeasures to prevent, or mitigate the effects of, threats to the system or network.

Telnet is a TCP-based, application-layer, internet standard protocol and an essential tcp/ip protocol for accessing remote computers. Through telnet, an administrator or another user can access someone else’s computer remotely.

A trusted certificate is any digital certificate that a certificate user accepts as being valid without testing the certificate to validate it as the final certificate on a certification path; especially a certificate that is used as a trust anchor certificate.

Trust determines which permissions and what actions other systems or users can perform on remote machines.

A TCP full open scan checks each and every port after performing a full three-way handshake on each port to determine if it was open.

Traceroute is a tool that maps the route a packet takes from the local machine to a remote destination. The history of the route is recorded as the round-trip times of the packets received from each successive host (remote node) in the route (path). The sum of the mean times in each hop indicates the total time spent to establish the connection.