ENUM-based Softswitch Requirement 19 Mar th IETF – Prague, Czech JoonHyung National Internet Development Agency of Korea (NIDA, former KRNIC)

68 th IETF 2 This Draft is… Advisory –Not defined any standard material –Providing a experience to help implementers Results of KR(+82) Infra ENUM trial –Evaluated the service quality between ENUM and Non-ENUM Still individual draft

68 th IETF 3 Changes since –ver.00 Major changes –Changed status of draft to “informational” –Added new sections for KR trial details Diagram of trial system in “section 3” Trial Result in “section 5” –Added specific implementation for softswitch using Rcode and routing method Editorial changes –Re-arranging order and re-naming the title of entire sections

68 th IETF 4 Requirement for ENUM-based softswitch (limited on KR trial) Routing path selection depending on Rcode –Rcode scenario implemented on trial system To route a call based on domain name, it can use –Fixed routing table embedded on softswitch Efficient for limited access among carriers based on previous agreement –External Recursive DNS Efficient for unlimited access among carriers Rcode valueNAPTR RRPath 0(No Error)URI(1 or more)Via Internet URI, but Non-routable(i.e. web, , etc.) (Call failed) 3(Name error), 1(Format Error), 2(Server Failure), 4(Not Implemented) or 5(Refused) No URIVia PSTN

68 th IETF 5 Trial Results Only difference between ENUM and Non-ENUM softswitch is the location where call routing information stored –Delay time can be a issue for performance “Answer Delay Time” defined as elapsed time between requesting a call('INVITE') and receiving a response('200OK’) There is little difference in time(under a sec) between ENUM and Non- ENUM case. Therefore a caller of each carrier is hard to recognize the difference as aspect of quality when a call initiates. Call TypeENUMNon-ENUM Carrier A->A (SIP) Carrier A->B (SIP) Carrier A->other(PSTN) Carrier B->B (SIP) Carrier B->A (SIP)2.19 Carrier B->other(PSTN) Answer Delay Time (sec)

68 th IETF 6 Still comments needed Can this draft contribute to WG by means providing Infra ENUM experience? Comments needed what if this draft going to make further progress (i.e. WG draft and so on.) Isn’t there any necessity to work on practical “Path selection” issue can be adopted on device widely ?

Thank you! Q/A