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Can you List all Known SIP Responses?

SIP responses are the codes used by Session Initiation Protocol for communication. We have put together a list of all the SIP responses known. 1xx = Informational SIP Responses 100 Trying – Extended search is being perform so a forking proxy must send a 100 trying response. 180 Ringing – The destination user agent has...

12/12/2018 | Read more

What are SIP Phones?

Simply put, a SIP phone is a phone that uses the Open Standard SIP to set up and manage phone calls. The actual voice is carried over an IP-based network using another Open Standard called RTP. Since these protocols are generically termed VoIP (voice over internet protocol), these phones are also sometimes...

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SIP Call Session Between 2 Phones

  A SIP call session between two phones is established as follows: The calling phone sends out an INVITE. The called phone sends an information response 100 – Trying – back. When the called phone starts ringing a response 180 – Ringing – is sent back. When the caller picks up the phone, the called...

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What SIP-Based IP PBX’s are Available?

An IP PBX or VoIP phone system replaces traditional PBX or phone systems, giving employees an extension number, the ability to conference, transfer and dial other colleagues. All calls are sent via data packets over a data network instead of the traditional phone network. With the use of a VoIP gateway, you can connect existing...

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What is a SIP Server?

  A SIP server is the main component of our IP 3CX, and mainly deals with the management of all SIP calls in the network. A SIP server is  also referred to as a SIP proxy or a registrar. Although the SIP server can be considered the most important part of a SIP-based IP-3CX phone system,...

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SIP Phones / VoIP Phones Types

A VoIP phone system requires the use of SIP phones / VoIP phones. SIP phones come in several versions and types: SIP / VoIP Soft Phones – Software-Based SIP Phone   A software-based SIP phone is an application which makes use of your computer’s microphone and speakers or an attached headset to allow you...

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What is SIP?

SIP (Session Initiation Protocol) is a signalling protocol used to establish a session between 2 or more participants, modify that session, and eventually terminate that session. It has found its major use in the world of IP telephony. The fact that SIP is an open standard has sparked enormous interest in the...

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What is SIP Forking?

SIP forking refers to the process of “forking” a single SIP call to multiple SIP endpoints. This is a very powerful feature of SIP. A single call can ring many endpoints at the same time.     With SIP forking you can have your desk phone ring at the same time as your softphone or...

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SIP Methods / Requests and Responses?

SIP Methods / Requests and Responses SIP uses methods / requests and corresponding responses to communicate and establish a call session.     SIP Requests There are fourteen SIP request methods of which the first six are the most basic request / method types: INVITE = Establishes a session. ACK = Confirms an INVITE request....

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What are SIP Trunks?

The trusted old Public Switched Telephone Network (PSTN), with its analogue lines, ISDN BRI, E1 or t1 lines, is to disappear. Telephony is moving from PSTN to much more modern and flexible SIP trunks. The big telecom providers are fast phasing out the old PSTN functionality, and are moving customers to IP....

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