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Both of them are not in the LAN. &nbsp;So I guess the reason why the Outbound Proxy is used in this instance is for policing purposes. I know for a fact that the number of SIP messages to the Outbound Proxy is being controlled and if there's too many, the IP will be blocked for a good ten minutes.<br />
<br />
Also, one thing I noticed is that this provider gives back an Unauthorised 404 each time the first invite goes. <br />
<br />
Any idea what this is?
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Both of them are not in the LAN.  So I guess the reason why the Outbound Proxy is used in this instance is for policing purposes. I know for a fact that the number of SIP messages to the Outbound Proxy is being controlled and if there's too many, the IP will be blocked for a good ten minutes.

Also, one thing I noticed is that this provider gives back an Unauthorised 404 each time the first invite goes.

Any idea what this is?

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Might be greylisting, other than that no idea.
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Might be greylisting, other than that no idea.

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Hi, what is the difference between an outbound proxy and a proxy server for SIP?<br />
<br />
Why are there 2 fields required for connection sometimes?<br />
<br />
I'm asking because my voip provider has provided me sip trunking 20 lines. They have said the outbound proxy needs to be a certain proxy, then the proxy server to be another one.<br />
<br />
It seems the calls have issues if the outbound proxy is set differently or not set at all. I experienced call drop outs and difficulty in registration.<br />
<br />
Can the provider do that?
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Hi, what is the difference between an outbound proxy and a proxy server for SIP?

Why are there 2 fields required for connection sometimes?

I'm asking because my voip provider has provided me sip trunking 20 lines. They have said the outbound proxy needs to be a certain proxy, then the proxy server to be another one.

It seems the calls have issues if the outbound proxy is set differently or not set at all. I experienced call drop outs and difficulty in registration.

Can the provider do that?

Outbound Proxy and Proxy Server for SIP

Telecommunication occurs when the exchange of information between two or more entities (communication) includes the use of technology. Communication technology uses channels to transmit information (as electrical signals), either over a physical medium (such as signal cables), or in the form of electromagnetic waves. The word is often used in its plural form, telecommunications, because it involves many different technologies.

Telecommunications

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).