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NAT - Network Address Translation - IP Address
NAT is an Internet standard that translates a private IP within one network to a public IP
address, either a static or dynamic one. NAT provides a type of firewall by hiding internal IP
addresses. It also enables a company to use more internal IP addresses.
If the IP addresses given by your ISP are not enough for each PC on the LAN and the
Router, you need to use NAT. With NAT, you make up a private IP network for the LAN and
assign an IP address from that network to each PC. One of some public addresses is
configured and mapped to a private workstation address when accesses are made through
the gateway to a public network.
For example, the Router is assigned with the public IP address of 168.111.2.1. With NAT
enabled, it creates a Virtual LAN. Each PC on the Virtual LAN is assigned with a private IP
address with default value of 192.168.1.2 to 192.168.2.254. These PCs are not accessible
by the outside world but they can communicate with the outside world through the public IP
168.111.2.1.
Network Mask
A number that allows IP networks to be subdivided for security and performance.
Network Provider
The vendor who provides your access to the Internet. Known by different names in different
regions, some examples are: wireless provider, network operator, and service provider.
Network Technology
The technology on which a particular network provider’s system is built; such as, xDSL,
PON, GPON, GSM, HSPA, CDMA, EDGE, and EVDO.
NNTP - Network News Transfer Protocol
An Internet application protocol for reading and posting Usenet (newsgroup) articles.
PDA - Personal Digital Assistant
A handheld device used for organization, notes, address books, etc.
POP - Post Office Protocol
An Internet protocol for retrieving email from a remote server over a TCP/IP connection.
Port.
A virtual data connection used by programs to exchange data. It is the endpoint in a
logical connection. The port is specified by the port number.
Port Forwarding
A process that allows remote devices to connect to a specific computer within a private LAN.
Port Number
A 16-bit number used by the TCP and UDP protocols to direct traffic on a
TCP/IP host. Certain port numbers are standard for common applications.
Private IP Address
Private IP addresses are also LAN IP addresses, but are considered “illegal” IP addresses to
the Internet. They are private to an enterprise while still permitting full network layer
connectivity between all hosts inside an enterprise as well as all public hosts of different
enterprises.
The Router uses private IP addresses by assigning them to the LAN that cannot be directly
accessed by the Internet or remote server. To access the Internet, private network should
have an agent to translate the private IP address to public IP address.
Protocol
A standard that enables connection, communication, and data transfer between computing
endpoints.
PPP - Point to Point Protocol
A method of connecting a computer to the Internet.
PPTP - Point-to-point Tunnelling Protocol
A method for implementing virtual private networks that does not provide confidentiality or
encryption but relies on the tunnelling process for security.
