Gigaset DE900 IP PRO / en / A31008-M2210-R101-5-7619 / glossary.fm / 17.09.2012
PRO Version 3, 30.05.2012
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Glossary
O
Outbound proxy
Alternative NAT control mechanism to STUN and ALG.
Outbound proxies are implemented by the VoIP provider in firewall/NAT environments as
an alternative to a SIP proxy server. They control data traffic through the firewall.
Outbound proxy and STUN servers should not be used simultaneously.
See also: STUN and NAT.
P
PIN
Personal Identification Number
Protects against unauthorised use. When the PIN is activated, a number combination has
to be entered to access a protected area.
Port
Data is exchanged between two applications in a network across a port.
Port forwarding
The Internet gateway (e.g., your router) forwards data packets from the Internet to the
port that the data is intended for. This allows servers in the LAN to offer services on the
Internet without you needing a public IP address.
Port number
Indicates a specific application of a network subscriber. Depending on the setting in the
LAN, the port number is permanently assigned or else it is newly assigned with each
access.
The combination of IP address/port number identifies the recipient or sender of a data
packet within a network.
Prepare dialling
See Block dialling.
Private IP address
See Public IP address.
Protocol
Describes the agreements for communicating within a network. It contains rules for open-
ing, administering and closing a connection, about data formats, time frames and possible
error handling.
Proxy/Proxy server
Computer program that controls the exchange of data between client and server in com-
puter networks. If the phone sends a query to the VoIP server, the proxy acts as a server
towards the phone and as a client towards the server. A proxy is addressed via the IP
address/domain name and port.
Public IP address
The public IP address is the address for a network component on the Internet. It is assigned
by the Internet service provider. Devices that act as a link from a local network to the Inter-
net (gateway, router) have a public and a local IP address.
See also: IP address, NAT.
