Register a SIP device through Twilio API

I was not able to find a way to register a SIP device using Twilio Client JS SDK ([login to view URL]) for a web application that I am creating in LAMP stack. It makes calls only as a client. I looked for an SDK with Twilio that would register my custom web application as a SIP device. I could not find a way to make this work. The other documentation I found on SIP from Twilio’s documentation, I was able to make calls with SIP but I did not find a way to register the custom web application as a SIP device ([login to view URL]). In other words, I am able to make SIP calls through the browser, but I cannot connect the microphone sound on the computer to hear the call. Currently, I have a SIP registration working through Twilio using programmable voice. This has been tested and the SIP endpoint connects with a third-party softphone I found from this page. [login to view URL] Right now, I am using a third-party API programmed in JavaScript to connect the web application that uses LAMP stack as a registered SIP endpoint. [login to view URL] The issue with this API is that it has poor connectivity. So, I want to use a different API and I need help getting it to work. Also, I would prefer to find an API that registers SIP with JavaScript.