Multitech RouteFinder RF560VPN, Руководство пользователя

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Glossary
Multi-Tech Systems, Inc. RF560VPN User Guide 80
S
Server
A provider of resources (e.g., file servers and name servers). For example, your RouteFinder
provides Internet access and is, therefore, an Internet Access Server.
Static Routing
Involves the selection of a route for data traffic on the basis of routing options preset by the network
administrator.
Subnet
A portion of a network that shares a common address component. On TCP/IP networks, subnets are
all devices whose IP Addresses have the same prefix. For example, all devices with IP addresses
starting with 213.0.0 are part of the same subnet.
SubnetMask /IPAddressMask
Subnet mask is what is used to determine what subnet an IP address belongs to. Subnetting
enables the network administrator to further divide the host part of the address into two or more
subnets.
T
TCP/IP (Transmission Control Protocol/Internet Protocol)
A suite of communication protocols used to connect hosts on the Internet. Every computer that
wants to communicate with another computer on the Internet must use the TCP/IP protocol to
transmit and route data packets. The format of an IP address is a 32-bit numeric address written
as four octets separated by periods. Each number can be zero to 255. Within an isolated network,
you can assign IP addresses at random as long as each one is unique. However, connecting a
private network to the Internet requires using registered IP addresses to avoid duplication.
The four groups of numbers (octets) are used to identify a particular network and host on that
network. The InterNIC assigns Internet addresses as Class A, Class B, or Class C. Class A
supports 16 million hosts on each of 127 networks. Class B supports 65,000 hosts on each of
16,000 networks. Class C supports 254 hosts on each of 2 million networks. Due to the large
increase in access to the Internet, new classless schemes are gradually replacing the system
based on classes.
Triple DES (3DES)
Cipher that applies the DES cipher three times with either two or three different DES keys.
Tunneling
As a n Internet term, tunneling means to provide a secure temporary path over the Internet or other
IP-based network in a VPN (Virtual Private Network) scenario. In this context, tunneling is the
process of encapsulating an encrypted data packet in an IP packet for secure transmission across
an inherently insecure IP network, such as the Internet.
U
UDP (User Datagram Protocol )
An Internet Standard transport layer protocol. It is a connectionless protocol that adds a level of
reliability and multiplexing to IP.
V
Virtual Private Network
A private network built atop a public network. Hosts within the private network use encryption to
talk to other hosts; the encryption excludes hosts from outside the private network even if they are
on the public network.
W
WAN (Wide Area Network)
A network that connects host computers and sites across a wide geographical area.