How to Use Linkus if SIP is Blocked by ISP


In some countries in Middle like UAE, Oman, Saudi Arabia etc, the SIP is blocked by the ISP. Linkus could not be used in that situation. Some countries even block RTP like Pakistan.

So how could we overcome this? Here we have the advice:

  • Change to use the TCP transport 
  • Change SIP port and use the TLS transport
  • Change to use LCS 
  • Use VPN to Connect Linkus Server



1. Change to use the TCP transport

1) enable TCP port on the PBX

2) select transport to TCP for extension


2. Change SIP port and use TLS transport

1) Enable TLS on PBX and change SIP port.



2) Select transport as TLS for extension


3. Change to Use LCS

Now we offer a 90-days free trial for LCS. The LCS data has been encrypted which can prevent being blocked by the ISP.


4. Use VPN to Connect Linkus Server

(If the ISP blocks RTP, you can try this solution)

If your PBX is on-premise type, you can setup VPN access for the PBX and your Linkus client.

Basically, you could ask your IT to deploy the VPN access for you.

Note that you need to manually input the login information and, the PBX VPN IP address to login the Linkus Server.

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