Assuming you want the OBi to register with Sip Sorcery using SP2/ITSP Profile B:
Service Providers -> ITSP Profile B -> SIP -> ProxyServer :
sipsorcery.comVoice Services -> SP2 Service -> AuthUserName : (sipsorcery.com username)
Voice Services -> SP2 Service -> AuthPassword : (sipsorcery.com password)
Voice Services -> SP2 Service -> X_ServProvProfile : B
Assuming you want an IPKALL DID to ring the OBi directly:
IPKall -> SIP username : (anything)
IPKall -> Hostname or IP address : ipaddress_or_hostname:port
where ipaddress_or_hostname is your public IP address or a hostname resolving to your public IP address and port is : 5060 = SP1 / 5061 = SP2 (the selected SP1/SP2 must be configured for SIP).
You may have to forward ports 5060 -5061 and 16600 - 16998 to your OBi in your router.