HTTP/1.1 200 OK Date: Tue, 09 Apr 2002 10:34:57 GMT Server: Apache/1.3.20 (Unix) Last-Modified: Mon, 06 Apr 1998 12:08:00 GMT ETag: "361d18-e94-3528c5a0" Accept-Ranges: bytes Content-Length: 3732 Connection: close Content-Type: text/plain INTERNET DRAFT Masataka Ohta draft-ohta-notasip-00.txt Tokyo Institute of Technology Kenji Fujikawa Kyoto University 1 April 1998 Nothing Other Than a Simple Internet Phone (NOTASIP) Status of this Memo This document is an Internet-Draft. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet- Drafts as reference material or to cite them other than as ``work in progress.'' To view the entire list of current Internet-Drafts, please check the "1id-abstracts.txt" listing contained in the Internet-Drafts Shadow Directories on ftp.is.co.za (Africa), ftp.nordu.net (Northern Europe), ftp.nis.garr.it (Southern Europe), munnari.oz.au (Pacific Rim), ftp.ietf.org (US East Coast), or ftp.isi.edu (US West Coast). Abstract This memo describes a simple protocol for Internet phone without QoS. It is assumed that the operating system support a connected UDP socket. 1. Caller Initiate the Call The caller host somehow (through SDP URL, for example) find the callee's IP address, UDP port number (with appropriate default) and desired encoding. The caller host opens a connected UDP socket and start sending Masataka Ohta Expires on April 2, 1998 [Page 1] INTERNET DRAFT NOTASIP March 1998 properly encoded UDP packets of voice. 2. Callee Accept the Call The callee host receiving a UDP packet from someone opens a connected UDP socket and start ringing the phone to notify the existence of a call to the callee person. The ringing tone should also be send to the caller. Or, if the port is already connected to someone else, ICMP unreach port error packet is returned, which makes the caller host generate a busy signal to the caller person. 3. Connection Established If the callee person hangs up a headset, the voice of the callee is sent to the caller and the call is established. 4. Interoperation with PSTN Interoperation with PSTN is performed through dial tone. The exact protocol is service provider dependent and MUST NOT be standardized. 5. Error Conditions If the connected UDP socket can not be created or the socket generates some error, the call terminate. If there is no packets received for 42 seconds, the call terminates. 6. Security Considerations The protocol is as secure as UDP. Authors' Addresses Masataka Ohta Computer Center Tokyo Institute of Technology 2-12-1, O-okayama, Meguro-ku, Tokyo 152, JAPAN Phone: +81-3-5734-3299 Fax: +81-3-5734-3415 Masataka Ohta Expires on April 2, 1998 [Page 2] INTERNET DRAFT NOTASIP March 1998 EMail: mohta@necom830.hpcl.titech.ac.jp Kenji Fujikawa Department of Information Science Kyoto University Yoshidahonmachi, Sakyo Ku, Kyoto City, 606-01, JAPAN Phone : +81-75-753-5387 Fax: +81-75-751-0482 Email : magician@kuis.kyoto-u.ac.jp Masataka Ohta Expires on April 2, 1998 [Page 3]