HP VCX Software manual Nat

Appendix D. Definitions of terms

Peter and Christy cannot know if all of their postcards will arrive, and Christy doesn’t know what order the postcards were sent in.

For more information about IP addresses, see IP address.

Kerberos

Kerberos is a system to secure connections between several computers over networks. The Kerberos system uses a Kerberos server to manage security. Connections that go through Kerberos are often encrypted.

Masquerading

See NAT.

Name server

See DNS.

NAT

NAT (Network Address Translation), also known as masquerading, is a way to hide a network from outside computers. Used with firewalls to hide the computers on the internal network from the rest of the world.

Netmask

See network mask.

Network mask

A network mask tells what computers can be accessed locally without using a gateway, and what computers can only be reached through a gateway. The bits in the network mask determine what is a network and what is a computer. The total number of bits is 32 and the "one-bits" are for networks. The network mask can be specified as the number of one-bits grouped in the same way as IP addresses. For what formerly was called a class C network, the network mask is 24, which can also be expressed as 255.255.255.0 (i.e., 24 one-bits grouped in octets and then interpreted as binary numbers). If this network is divided into several parts, the network mask is different, depending on how the division is done. For example, the network mask 255.255.255.224 gives a network with 32 IP addresses in it. See also the table of network masks in appendix C, Lists of Reserved Ports, ICMP Types and Codes, and Internet Protocols.

News

News is a distributed, loose conference system, which includes the entire Internet and more. News originated in email, so it has many similarities to email. It can also be called Usenet News and NetNews.

News is a conference system for exchange of ideas, questions and answers, and so on, just like in a BBS or COM system. What is written in News is not stored on a central computer; it is sent out all over the world and stored in several places. Your organization may choose to retrieve News and store all texts locally.

To keep track of everything, News is divided into news groups. A news group focuses on a specific area of interest. Each news group can have divisions and subgroups.

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