Gets SIP address what is used for registration mapping. (This is To: address of record value.)
For example: ivar@lumisoft.ee.
Assembly: LumiSoft.Net Version: 2.0.2636.18419 (Module: LumiSoft.Net)
Assembly: LumiSoft.Net Version: 2.0.2636.18419 (Module: LumiSoft.Net)