The document discusses a SIP-ISDN gateway being developed using Erlang/OTP. It describes using SIP for initiating multimedia conferences over IP and integrating SIP with web services. It also summarizes using Erlang/OTP to build the gateway due to its support for concurrency, distribution, and hot code upgrades.

1. A SIP-ISDN Gateway Hans Nilsson CSLab Ericsson Utvecklings AB [email_address]

2. What is SIP ? S ession I nitiation P rotocol, RFC 2345 Initiating, Changing and Terminating Multimedia conferences (IP Telephony) Lightweight Textbased ”Looks like HTTP” UDP (TCP)

3. Future of SIP? Easy to implement => many small companies Mail servers, HTTP Servers, SIP servers [email_address] sip:hans@cslab.ericsson.se Web integration; Services on web pages Click-to-dial

4. SIP, Simple Example Audio, video, ... INVITE 200 OK ACK BYE 200 OK

5. SIP Redirect Server Example INVITE 200 OK INVITE 200 OK • • • 302 Redirect REGISTER

6. SIP, Other Example REGISTER REGISTER

7. What is a Gateway? Audio

8. SIP/ISDN Gateway Signalling Gateway Media Gateway Controller Media Gateway ISDN SIP RTP PCM

9. SIP - ISDN SIP stack SIP stack ISDN stack State machine Encode Decode Resending TCP UDP Message support SNMP HTTP

10. Erlang code sizes in number of source lines

11. SIP/ISDN Gateway - realisation SwitchBoard IP Network IPI 100BaseT RTP 4 x E1/T1 ISDN Network PCI ISDN DSS1 SIP 10BaseT IP Network Distributed Erlang

12. Why Erlang/OTP?

13. Hot code upgrade External interfaces Components/Libraries: Mnesia SASL SNMP Inets GS ... Concurrency lightweight processes Distribution transparent message passing Robustness node fail-over process monitoring Soft real-time Some characteristics [ http://www.erlang.org/white_paper.html ]

14. Users

15. Mobility Server VoIP Prototype Configuration NT Server: Mobility Server ISDN SIP H.323 DECT SWB PLMN PTN IPI RE H.323 IP H.323 SIP Wireless LAN PSTN TNI Feature Feature Feature

16. Show Inter-operability between IP Terminals and DECT Terminals or PSTN Identify effects from implementing existing Mobility Server services over VoIP Create qualified arguments on SIP versus H.323 for the Mobility Server product Mobility Server VoIP Prototype Objectives

17. The Future

18. Future: Work, work, work... Standard MG protocol (MGCP,…) Less prototypish :-) Administration: SNMP HTTP/CGI Connect to Ericsson Phone Network

19. Redundancy and Capacity “ Eddie ” SIP SwitchBoard IPI PCI SwitchBoard IPI PCI SwitchBoard IPI PCI “ Eddie ” “ Eddie ”