Hi
What could be the main reason when linkus does not connect in some networks. do we need Qos on the network for it to work.
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Larry Neblett It may be attributable to a number of things, but given that you have indicated "some networks", implies that it works in others. Understanding that it does seem to work, even if only in others, tends to indicate that it is configured correctly, which then leads us to the question of what "does not connect" really mean? Does the phone register or is it unable to connect in order to do so? Is it registered and you dial, but cannot seem to connect to the person dialed or vice versa?
Usually either is attributable to:
1. Some will purposely block ports in order to prevent VoIP from traversing their firewall.
2. Some may not block, but already utilize the ports for some other application, which effectively does the same as blocking.
3, The router that is handling the LINKUS traffic side may not be handling the SIP messaging correctly as it may have some form of SIP ALG enabled.
4. It is a two-way street in that LINKUS and the PBX must be able to communicate with one another. So, LINKUS may be able to reach the PBX, but not the other way around.
A capture may provide some insight, but when connected to a network that is not under your control, there is always the possibility of something not getting through the NAT correctly.
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Shufflel Hi Larry
Thanks for your response.To shed more light on my problem, my PBX's (S-50) is using public IP:
- When the Firewall on the s-50 is on it block the IP every time when a device is trying to connect from a different network.
- I realized that at home my bandwidth is 124 / 511 kbps/kbps and I never connect when I am there.
I am not sure if I need QoS on the router and what QoS I need to set on the S-50.
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Larry Neblett QoS is not the answer. It will not force a connection. QoS is used to identify and then accelerate those packets to the front of the line (queue) when the router has reached the limits of the WAN connection speed. By doing so, the possibility of the router having to drop packets in order to maintain the flow is minimized, but not eliminated....depending on just how saturated the connection is and how much the router can handle in the queue.
Your connection at home is marginal in my opinion, but this depends on the codec in use. If using anything other than a low rate codec, you may not be able to sustain a reliable voice stream if other data is flowing at the same time. Even then, using low rate codecs may become an issue should the normal data flow be unbridled. In this case QoS will help, but again it can only do so much.
However, getting LINKUS to register should not be an issue provided that the a) your firewall at home is allowing the data to traverse without mangling the headers and the NAT IP is correct. b) that the firewall at the office, which we believe to be configured correctly given that you indicated that it works for some networks, is not programmed to allow only some IPs and not others.
What make and model is the router/firewall at the house?
Looking at the LINKUS settings, what IP or FQDN shows in the SIP server?
Does the LINKUS extension show registered at the S PBX?
When at the house, log in remotely to the S PBX and start a capture and then start-up LINKUS after the capture is running. Submit the capture.
If nothing happens, then turn off the firewall and repeat the above for another capture and submit.
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Shufflel Hi Larry
Thanks you very much for your help. I gave Andrew Weng acces to the BX earlier and he sorted me out. he adjusted QoS settings and turned of the firewall. we seem to be ok.
Thanks again the points you raised will definitely help me in future installations.
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