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&gt;&gt; The phones<br />
What kind (brand/type) phones are they?<br />
<br />
Is the time correct on your CentOS machine?
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>> The phones
What kind (brand/type) phones are they?

Is the time correct on your CentOS machine?

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We have a mixer of phones. <br />
<br />
Polycoms Models: IP 301 SIP, IP 335<br />
<br />
Astra 6757i
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We have a mixer of phones.

Polycoms Models: IP 301 SIP, IP 335

Astra 6757i

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OK and what about:<br />
<br />
&gt;&gt;Is the time correct on your CentOS machine?
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OK and what about:

>>Is the time correct on your CentOS machine?

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I have a about 20 IP phones that connect to a TrixBox CentOS box that handles the VOIP. The time and date on the phones is always off and has never worked. The phones should auto update from the web but do not.
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I have a about 20 IP phones that connect to a TrixBox CentOS box that handles the VOIP. The time and date on the phones is always off and has never worked. The phones should auto update from the web but do not.

TrixBox Phone system

Voice over IP (VoIP) is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. Other terms commonly associated with VoIP are IP telephony, Internet telephony, broadband telephony, and broadband phone service. The term specifically refers to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the public Internet, rather than via the public switched telephone network (PSTN).  Examples of the VoIP protocols are H.323, Media Gateway Control Protocol (MGCP), Session Initiation Protocol (SIP), H.248 (also known as Media Gateway Control (Megaco)), Real-time Transport Protocol (RTP), Real-time Transport Control Protocol (RTCP), Secure Real-time Transport Protocol (SRTP), Session Description Protocol (SDP), and Inter-Asterisk eXchange (IAX).

Voice Over IP

Linux is a UNIX-like open source operating system with hundreds of distinct distributions, including: Fedora, openSUSE, Ubuntu, Debian, Slackware, Gentoo, CentOS, and Arch Linux. Linux is generally associated with web and database servers, but has become popular in many niche industries and applications.

Linux

IP telephony (Internet Protocol telephony) is 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). Using the Internet, calls travel as packets of data on shared lines, avoiding the tolls of the PSTN. The challenge in IP telephony is to deliver the voice, fax, or video packets in a dependable flow to the user.