Standard; Dhcp; Tftp; Nat - Avaya 4600 Series Administrator's Manual

G.729A and G.729B, which describes adaptive code-excited linear-predictive (CELP)
compression that enables voice to be coded into 8 kbps streams.
H.323 Standard
Internal signaling provides connection control and call progress (status) information. The H.323
standard is used for internal signaling for IP packet voice networks. H.323 defines more than
simply voice. It defines a complete multimedia network (voice, video, data), with everything from
devices to protocols. The H.245 standard links all the entities within H.323 by negotiating facilities
among participants and H.323 network elements.
The H.323 standard makes G.711 PCM compression the default form of compression. All other
compression formats are optional.

DHCP

Dynamic Host Configuration Protocol (DHCP) allows a server to assign IP addresses and other
parameters to devices such as the 4600 Series IP Telephones on an as-needed basis. This
eliminates the need to configure each end station with a static IP address. The DHCP also passes
information to the 4600 Series IP Telephone, identifying the IP Addresses of the DEFINITY switch
and the TFTP server and the path to the upgrade script and the application file on the TFTP server.
For further information, refer to ''DHCP and DEFINITY Servers'' on page 2-8 and ''DHCP'' on page
4-3.

TFTP

During the installation and, if necessary, during the reset of the 4600 Series IP Telephones, the
upgrade script and the application file are downloaded from the Trivial File Transfer Protocol
(TFTP) server to each IP Telephone, simplifying the software upgrade process. For further
information, refer to ''TFTP'' on page 4-13.

NAT

A Network Address Translator is an application that can be administered between your network
and the Internet. The NAT translates network layer IP addresses so your local intranet IP
addresses can duplicate global, Internet addresses. A detailed discussion of NAT is beyond the
scope of this document, but it should be noted that use of NAT can lead to problems affecting the
consistency of addressing throughout your network and is not recommended for networks
handling IP-based telephony.

QoS

Quality of Service (QoS) is a term covering several initiatives to maximize the quality of the voice
heard at both ends of a call that originates, terminates, or both, on an IP-based telephone. These
initiatives include various prioritization schemes to offer voice packets a larger or prioritized share
of network resources. These schemes include standards such as IEEE's 802.1D and 802.1Q, the
Internet Engineering Task Force's (IETF's) "Differentiated Services", and port-based priority
Overview of Voice over IP (VoIP)
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Overview of Voice over IP
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