Network+ Guide to Networks, Chapter 12, Part 2

Key based encryption system for e-mail that uses a two-step verification process

A practice in which a person attempts to glean access or authentication information by posing as someone who needs that information

Use of certificate authorities to associate public keys with certain users.

Technique in which a client identity is verified by an authentication server before a port, whether physical or logical, is opened for the client's Layers 3 traffic

The process of redirecting traffic from its normally assigned port to a different port, either on the clients or server. In the case of using SSH , it can send data exchanges that are normally insecure through encrypted tunnels.

Monitoring technique in which one port on a switch is configured to send a copy of all its traffic to a second port

Software that searches a server, switch, router, or other device for open ports which can be vulnerable to attack

In Kerberos terminology , a user or client

A type of key encryption in which the sender and receiver use a key to which only they have access. DES which was developed by IBM in the 1970 is a popular example of it. it is also called symmetric encryption

Network host that runs a proxy service. Proxy servers may also be called gateways

Software application on a network host that acts as an intermediary between the external and internal networks, screening all incoming and outgoing traffic and providing one address to the outside world , instead of revealing the addresses of internal LAN devices.

Form of key encryption in which data is encrypted using two keys one is a key known only to a user, and the other is a key associated with the user and that can be obtained from a public source, such as a public key server. examples of public key algorithms include RSA and Diffie-Hellman. it is also known as asymmetric encryption

A publicly available host (such as an Internet host) that provides free access to a list of user's public keys

Protocol that runs over UDP and provides centralized network authentication and accounting for multiple user it is commonly used with dial-up networking, VPNs and wireless connection

Server that offers centralized authentication services to a network access server, VPN server or wireless access point via the RADIUS protocol