Glossary
Multi-Tech Systems, Inc. RF560VPN User Guide
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telephone number. It identifies one address or in this case one computing device. Every computer
or device on the network must have a different IP address.
An IP address consists of four groups of numbers called
octets
, which are separated by periods.
For example, 213 .0.0.1 is an IP address. An IP address consists of a
network portion
and a
host portion
. The network portion identifies the subnet that the computer belongs to. The host
portion identifies the particular computer or node on that network.
IP addresses can either be dynamic (temporary) or static (permanent or fixed). A dynamic IP
address is a temporary IP address that is assigned to you by a server (usually a DHCP server)
when the computer is powered on. A static IP address is a permanent IP address that is set up on
each individual computer. When your RouteFinder dials-up your ISP, your ISP can give it a fixed
or dynamic IP address. Likewise, when you power on your computer, the RF560VPN can give
your computer a dynamic or fixed IP address.
ISDN TA
(Integrated Services Digital Network Terminal Adapter) ISDN is a high speed digital telephone
connection involving the digitization of the telephone network using existing wiring. An ISDN
Terminal Adapter can be thought of as an ISDN Modem.
ISP (Internet Service Provider)
An organization that provides Internet services. An ISP is the company that provides the
connection from your computer to the Internet. An ISP can offer a range of services, such as dial-
up accounts, e-mail, web hosting or News.
L
LAN (Local Area Network
)
A data network intended to serve an area of only a few square kilometers or less. This often
means a small private network in companies.
M
ML-PPP (Also called MP or MPPP)
Stands for Multilink Point to Point Protocol and is an advancement of the PPP protocol that allows
for the bridging or bundling of two ISDN or analog channels for faster connections.
MAC Address
The hardware address of a Device connected to a shared media. To find out the MAC address of
your computer please see
Troubleshooting.
N
NAT Technology
NAT is short for Network Address Translation. NAT is an Internet standard that enables a local-
area network to use one set of IP addresses for internal traffic and a second set of IP addresses
for external traffic. The RF500S provides the necessary IP address translations. NAT is
sometimes referred to as “IP Address Masquerading”. This technology provides a type of firewall
by hiding the internal IP addresses.
How does it work?
Every IP address on the Internet is a Registered or legal IP address. Therefore, no two IP
addresses on the Internet are the same. For you to use your network device to access the Internet
you need a registered IP address from your ISP (Internet Service Provider). Using a registered IP
address on your Intranet or LAN is not necessary. When clients on your network start surfing the
Internet, your RouteFinder will receive all the requests for information. The RouteFinder will dial-
up your ISP and your ISP will give your RouteFinder a registered legal IP address. Your
RouteFinder uses this IP address to request information saying, “send all information back to me
at this IP address”. In essence it appears as though all your clients requests are coming from that
one IP address (hence the name IP masquerading). When all the information comes back through
the RouteFinder, it sorts the data using an Address Translation Table and returns the data to the
computer on your network that requested it.
If someone on the Internet tries to access your network, the firewall function of the RouteFinder
stops the request. The device will not reverse translate network addresses unless you have
specifically allowed this feature using the Virtual Server function (IP Mapping).
