XCON Working Group M. Brunner Internet-Draft NEC Expires: April 20, 2004 October 21, 2003 Issues and Requirements in Floor Control draft-brunner-xcon-fc-00 Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. 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." The list of current Internet-Drafts can be accessed at http:// www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on April 20, 2004. Copyright Notice Copyright (C) The Internet Society (2003). All Rights Reserved. Abstract This documents lists issues and requierements for floor control in conferencing applications. It is meant in addition to the existing requirements draft "raft-koskelainen". It basically proposes to do floor control in a policy less way. Meaning that the policies are built into the floor dcontrol server, but not part of the protocol. Brunner Expires April 20, 2004 [Page 1] Internet-Draft Issues in Floor Control October 2003 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.1 Scope of the floor . . . . . . . . . . . . . . . . . . . . . . 5 3.2 Number of users concurrently holding the floor . . . . . . . . 5 3.3 Floor Control Policies . . . . . . . . . . . . . . . . . . . . 5 3.4 Explicite versus implicite floor passing . . . . . . . . . . . 5 3.5 Floor passing trigger . . . . . . . . . . . . . . . . . . . . 6 3.6 Activity awareness . . . . . . . . . . . . . . . . . . . . . . 6 4. Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 7 Informative References . . . . . . . . . . . . . . . . . . . . 8 Author's Address . . . . . . . . . . . . . . . . . . . . . . . 8 Intellectual Property and Copyright Statements . . . . . . . . 9 Brunner Expires April 20, 2004 [Page 2] Internet-Draft Issues in Floor Control October 2003 1. Introduction Floor control is a mechnism used to deal with concurrecy in distributed systems. So it basically deals with the question who is allowed to generate input or change/write to a resource. In the context of conferencing systems floor control has two different goals. First it is about who is allowed to "speak" by sending data input into the conference, so has to do with access control. Second, there are some applications which also require the ordering of input in order to work correctly (single input/sequential input applications). In the laterc ase floor control can help to create correctly functioning applications. Brunner Expires April 20, 2004 [Page 3] Internet-Draft Issues in Floor Control October 2003 2. Terminology floor - the right to generate some input. floor control - determines at any given point in time, which entity is allowed to provide input, where entity could mean a user or an automated application. floor holder - user currently allowed to provide input. floor control mechanisms - the low-level protocol handling the floor control. floor control policy - the rules for a certain operation of floor control. Brunner Expires April 20, 2004 [Page 4] Internet-Draft Issues in Floor Control October 2003 3. Issues 3.1 Scope of the floor The floor can be assigned to various entities. E.g., a floor for a single session, an application, a conference. We assume an application can have several session, and a conference can have several applications. The floor can be bound to any of these entities. There is naturally a dependency on what application the floor control mechnisms is used for. 3.2 Number of users concurrently holding the floor It is possible that several users concurrently hold the floor. For example, in the case of audio input to the conference, it is then mixed together. Other applications such as shared workspaces/ application sharing might have a problem with concurrent input. 3.3 Floor Control Policies Floor control policies define the way how the floor is passed around. Here are some examples of floor passing: - ring passing: the current floor holder must explicitly release the flooer before anyone else can axquire it. - Preemptive: any user can grab the floor at any time - Timeouts: a user looses the floor after a period of inactivity or after a given time holding it. - Moderated: a designated user has control over passing the floor. - IETF meetings: mostly moderated with queueing of floor requests. 3.4 Explicite versus implicite floor passing Explicite floor passing requieres an explicit action of a user passing the floor. Implicit floor passing automatically gives the floor to a user as soon as he generates input. Implicit floor passing together with a preemtive policy corresponds actually to the case of having no floor control at all. For conversations this means also that a social protocl and etiques is needed. Implicit floor passing is much easier from users point of view, since no expicit action is requiered. Since the floor might be passed implicitly there need to be a group of users eligible to get the floor, where others might not get the floor implicitly. In the IETF Brunner Expires April 20, 2004 [Page 5] Internet-Draft Issues in Floor Control October 2003 meeting example, the floor can implicitly pass between all the people having a microphone, where others waiting in the queue are not eligable for getting the floor implicitly. 3.5 Floor passing trigger In implicit floor passing there needs to be a trigger to pass the floor automatically. Specifically in multi-application/session conference the trigger can be chosen freely. E.g., the person start speaking also get the floor for the shared whiteboard etc. 3.6 Activity awareness In conferencing scenarios users normally want to be aware what is going only. So for exmple they might want to know who currently has the floor etc. Brunner Expires April 20, 2004 [Page 6] Internet-Draft Issues in Floor Control October 2003 4. Requirements MUST allow for various scopes MUST have single and concurrent floor holders MUST be independent of a particular floor control policy. The policy should be part of a particular implementation, not of the mechnisms itself. MUST be able to restrict the group of users eligible for implicit floor passing. MUST provide means for distributed floor information (e.g., current floor holder to other participants SHOULD allow for transporting trigger filter information. What triggers the implicite floor control change Brunner Expires April 20, 2004 [Page 7] Internet-Draft Issues in Floor Control October 2003 Informative References [1] Koskelainen, P., "Requirements for Floor Control", DRAFT draft-koskelainen-xcon-floor-control-req-00.txt, June 2003. Author's Address Marcus Brunner Network Laboratories, NEC Europe Ltd. Kurfuersten-Anlage 36 Heidelberg 69115 Germany Phone: +49 (0) 6221 905 11 29 EMail: brunner@ccrle.nec.de Brunner Expires April 20, 2004 [Page 8] Internet-Draft Issues in Floor Control October 2003 Intellectual Property Statement The IETF takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. 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