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Hi<br />
<br />
I'm actually using PRTG to monitor the uptime and jitter at the moment. Over the last 2 hours it has been up 100% and the jitter on average is between 5 and 10 with a couple of small spikes of about 20ish. I read online that if it is around 10 its good for IP phones.
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Hi

I'm actually using PRTG to monitor the uptime and jitter at the moment. Over the last 2 hours it has been up 100% and the jitter on average is between 5 and 10 with a couple of small spikes of about 20ish. I read online that if it is around 10 its good for IP phones.

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Hi<br />
<br />
We have just recently opened up a new office in Spain and one of the services we have made available to them is VOIP via are SIP trunks here in London.<br />
<br />
The requirements of this set-up is that the voice has to come though London to are controller and then out to the Internet. We have got this working great but the connection between the phones in Spain and are controller is intermittent and the phones keep loosing service which is very annoying.<br />
<br />
We have managed to get the latency down over the vpn from 350ms to 137ms. The VPN is always up and we don't lose any pings but it keeps saying on the controller that its occasionally &nbsp;missing heartbeats between the phones and controller. I have prioritized the traffic on both sides. We have got good bandwidth on either side of the link.<br />
<br />
Any ideas as to what could be happening here or how I might improve the situation? Are system is Mitel if that helps.
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Hi

We have just recently opened up a new office in Spain and one of the services we have made available to them is VOIP via are SIP trunks here in London.

The requirements of this set-up is that the voice has to come though London to are controller and then out to the Internet. We have got this working great but the connection between the phones in Spain and are controller is intermittent and the phones keep loosing service which is very annoying.

We have managed to get the latency down over the vpn from 350ms to 137ms. The VPN is always up and we don't lose any pings but it keeps saying on the controller that its occasionally  missing heartbeats between the phones and controller. I have prioritized the traffic on both sides. We have got good bandwidth on either side of the link.

Any ideas as to what could be happening here or how I might improve the situation? Are system is Mitel if that helps.

SIP and VPN`

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

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.

IP Telephony

Cisco PIX is a dedicated hardware firewall appliance; the Cisco Adaptive Security Appliance (ASA) is a firewall and anti-malware security appliance that provides unified threat management and protection the PIX does not. Other Cisco devices and systems include routers, switches, storage networking, wireless and the software and hardware for PIX Firewall Manager (PFM), PIX Device Manager (PDM) and Adaptive Security Device Manager (ASDM).