Connecting Avaya phone to ringcentral DigitalLine service

[andersoj]

Greetings:

I have for a few years used an SPA-3102 to connect my POTS home telephone system to a ringcentral DigitalLine VOIP connection. This has worked fine, but the phone system is aging and I lack a decent speakerphone. My employer has been investing in a new phone system (but I am a teleworker), and I now have an Avaya 4621SW station to use, if I can make it work. I've managed to get TFTP set up to satisfy the phone, but I'm now at the point where I want to configure it to connect via SIP to the ringcentral servers, and I'm stuck. Apparently the Avaya has limited features for authenticating to a server (likely assuming it will only be used as part of an Avaya media server configuration.) In particular, the "extension" setting only allows for 7 or so characters, when I need an 11-digit number for my ringcentral user ID. (And I have no idea how avaya's extension ID maps to SIP authentication)

Question 1)
Is there a way to configure the Avaya to connect directly to a SIP provider like RingCentral (specifying SIP domain, outbound proxy, user name, password, and authorization ID)? In this case, I am happy no longer using the SPA3102

Question 2)
If (1) is not possible, can I configure the Avaya to register with the SPA3102 and forward calls on to the RingCentral proxy?

Question 3)
If (2) not possible, can someone direct me to the basic details of configuring asterisk for this configuration?

I've done several weeks of RTFM'ing, but I have to confess I'm baffled. I'm a fairly competent programmer and computer engineer, but know very little about VOIP/SIP.

Thanks in advance, and happy to field further RTFM suggestions if they include a reference...

JA

[aijazahmad]

hi, i have some problem in sip configoration plz i want help give me any user who can help my problem