SIP Calls

If you know what is SIP, click below:

• SIP call PSTN free (free trial)
• SIP routed to PSTN free (coming soon...)
• SIP free account
• SIP web phone
• SIP call back (coming soon...)
• SIP clients (good ones)(coming soon...)

Don' t know what is SIP? See below:


SIP is a voip phone number, somewhat like email, ie: yesfreecallyes@sip2sip.info
If you don't understand what it is, just regard it as a phone number, which can receive incoming calls.


The traditional phone number is 001-800-373-3411, this is PSTN;
While SIP is like email format: yesfreecallyes@sip2sip.info


How SIP works?
1. Call out
   -SIP can call PSTN; (usually, it is not free, most are free trial)
   -SIP can call SIP; (usually, it is free, but not for all)
2. Incoming call
   -SIP can receive incoming calls from SIP (usually, it is free, but not for all)
   -Some PSTN such as virtual phone number (IPKALL or UKDDI) can route calls to SIP, when someone calls your IPKALL or UKDDI number, your SIP will ring (some are charged some are free).

[more] Please refer to the relative sidebar menu for more information.