Snom ONE IP, Техническое руководство

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GLOSSARY
SIP (Session Initiation Protocol)
Address mask
A bit mask used to identify which bits in an IP address correspond to the network
portion of the Internet address and which ones correspond to the subnet portions
of the address. The address mask is often referred to as the subnet mask because
the network portion of the address can be determined by the class inherent in an
IP address. The mask is 32 bits long: ones are in positions that correspond to the
network and subnet numbers, and zeros are in the host number positions.
Address resolution
The translation of an Internet address into the hardware address or IP of a net-
work interface card (NIC). Because names are easier for people to remember,
they are usually used in place of the numerical machine address to identify a
piece of hardware. However, before instructions can be executed, the name must
be translated into the numerical address of the hardware. This function is done
by Address Resolution Protocol (see “ARP”). The terms “address resolution” and
“name resolution” are synonymous.
ANI (Automatic Number Identification)
The phone number of the calling party. Used for billing and lookup purposes.
ARP (Address Resolution Protocol)
A network protocol used for determining a network host’s link layer or hardware
address when only its Internet layer or network layer address is known. Using
the IP address of the target node, the client station broadcasts an ARP request
onto the network. The node that has that address responds by sending back its
physical address so that packets can be transmitted. Because ARP requests are
broadcast onto the network, every station in the subnet is required to process the
request. ARP returns the layer 2 address for a layer 3 address.
ATA (Analog Telephony Adapter)
A device used to connect one or more standard analog telephones to a digital
and/or non-standard telephone system such as a Voice Over IP based network.