Motorola HH1620, Руководство пользователя

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Examines packet headers on context established by previous packets
that traversed the firewall
Monitors the connection state and saves it in a table
Closes ports until a connection to a specific port is requested
May examine the packet contents up through the application layer to
determine more than just the source and destination
A stateful-inspection firewall is more advanced than a static filter firewall.
Static Filter A type of firewall that examines the source and destination in the packet
header based on administrator-defined rules only.
Static IP address An IP address that is permanently assigned to a host. Normally,
a static IP address must be assigned manually. The opposite of dynamic
IP address.
Subnet Mask A bit mask that is logically ANDed with the destination IP address of a
packet to determine the network address. A router routes packets using
the network address.
Subnetwork A part of a network; commonly abbreviated “subnet.” When subnetting is
used, the host portion of the IP address is divided into a subnet and host
number. Hosts and routers use the subnet mask to identify the bits used
for the network and subnet number.
TCP Transmission Control Protocol provides reliable transport over the network
for data transmitted using IP. It defines rules and procedures for data
exchange.
TCP/IP The Transmission Control Protocol/Internet Protocol is a set of protocols
that provides rules for communication between networks. It is the
worldwide internetworking standard and the basic communications protocol
of the Internet.
TFTP
Trivial File Transfer Protocol is a very simple protocol used to transfer files.
Unicast A point-to-point data transmission sent from one sender to one receiver.
This the normal way you access websites. See also multicast.
UPnP Universal Plug and Play protocol.
UPS A universal power supply provides battery back-up for a specified time
during a power outage.
Upstream In a cable data or DSL network, the direction of data sent from your
computer to the Internet.
USB Universal Serial Bus
Wireless Access
Point (WAP) A device that provides network connectivity to one or more client
computers using radio signals over a wireless connection. One example
you could use with your voice gateway is the
Motorola Wireless Access
Point WA840G .
VoIP Voice over Internet Protocol is a method to exchange voice, fax, and other
information over the Internet. Voice and fax have traditionally been carried
over telephone lines using a dedicated circuit for each line. VoIP enables
calls to travel as discrete data on shared lines.
VoIP provider The company from which you purchase VoIP telephone service.
VPN
A virtual private network is a private network that uses “virtual” connections
(tunnels) routed over a public network (usually the Internet) to provide a
secure and fast connection, usually to users working remotely at home or
in small branch offices. A VPN connection provides security and
performance similar to a dedicated link (for example, a leased line), but at
much lower cost.
WAN
A wide-area network provides a connection over a large geographic area,
such as a country or the whole world. The bandwidth depends on need
and cost, but is usually much lower than for a LAN. For the voice gateway,
“WAN” refers to the VoIP and broadband provider networks.
HH1620 Wireless VoIP Gateway
User’s Guide
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