Grandstream Networks GXV-3000

GXV-3000 User Manual Grandstream Networks, Inc.

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The intent of H.264/AVC has been to create a standard that would be capable of providing

good video quality at bit rates that are substantially lower (e.g., half or less) than what previous

standards would need (e.g., relative to MPEG-2, H.263, or MPEG-4 Part 2).

HTTP

Hyper Text Transfer Protocol; the World Wide Web protocol that performs the request and

retrieve functions of a server

Internet Protocol. A packet-based protocol for delivering data across networks.

IP-PBX

IP-based Private Branch Exchange

IP Telephony

(Internet Protocol telephony, also known as Voice over IP Telephony) A general term for the

technologies that use the Internet Protocol's packet-switched connections to exchange voice,

fax, and other forms of information that have traditionally been carried over the dedicated

circuit-switched connections of the public switched telephone network (PSTN). The basic steps

involved in originating an IP Telephony call are conversion of the analog voice signal to digital

format and compression/translation of the signal into Internet protocol (IP) packets for

transmission over the Internet or other packet-switched networks; the process is reversed at the

receiving end. The terms IP Telephony and Internet Telephony are often used to mean the

same; however, they are not 100 per cent interchangeable, since Internet is only a subcase of

packet-switched networks. For users who have free or fixed-price Internet access, IP Telephony

software essentially provides free telephone calls anywhere in the world. However, the

challenge of IP Telephony is maintaining the quality of service expected by subscribers.

Session border controllers resolve this issue by providing quality assurance comparable to

legacy telephone systems.

IVR

IVR is a software application that accepts a combination of voice telephone input and touch-

tone keypad selection and provides appropriate responses in the form of voice, fax, callback, e-

mail and perhaps other media.

MTU

A Maximum Transmission Unit (MTU) is the largest size packet or frame, specified in octets

(eight-bit bytes), that can be sent in a packet- or frame-based network such as the Internet. The

maximum for Ethernet is 1500 byte.

NAT

Network Address Translation

NTP Network Time Protocol, a protocol to exchange and synchronize time over networks

The port used is UDP 123

Grandstream products using NTP to get time from Internet