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Dear all,
We have an Archer C2600 in our company running the Internet connection. We have now a 3CX VOIP installation, which recommends to disable SIP ALG on the router.
In many models it can be disable with a simple tick, but there is no SIP ALG on the Archer C2600 Web interface.

The official guide to disable SIP ALG ( https://www.tp-link.com/lk/faq-343.html) uses Telnet. I have installed telnet and tried to connect to the router, but the connection fails.
Is there a way to enable Telnet? Is it listening to port 23?

Waiting for some suggestions,
With regards

Nick