1. P2P Streaming Protocol (PPSP) Requirements draft-zong-ppsp-reqs-02 Ning Zong Yunfei Zhang Victor Pascual Carl Williams

2. Requirements Overview General functionalities of PPSP tracker protocol and basic types of information communicated by PPSP tracker protocol. General functionalities of PPSP peer protocol and basic types of information communicated by PPSP peer protocol. Error handling and overload protection requirements. Security requirements.

3. PPSP Tracker Protocol Requirements PPSP tracker protocol MUST be able to carry peer list information, such that each peer can get the list of peers which could provide the content. PPSP tracker protocol MUST be able to carry peer list information, such that each peer can get the list of peers which could provide the content. PPSP tracker protocol MUST be able to carry swarm ID (e.g. channel ID, streaming file ID). PPSP tracker protocol MUST be able to carry swarm ID (e.g. channel ID, streaming file ID).

4. PPSP Tracker Protocol Requirements PPSP tracker protocol MAY carry content availability of the peers. PPSP tracker protocol MAY carry content availability of the peers. - In some cases tracker may maintain the information of which pieces of content reside in which peers, such that the tracker can assign the appropriate peers for the requesting peer. PPSP tracker protocol MAY carry streaming status of the peers. PPSP tracker protocol MAY carry streaming status of the peers. - Streaming status of the peer include online time, link type/status, peer capability, device types, etc. Therefore, the tracker is able to select better candidate peers based on the streaming status of the peers. PPSP tracker protocol MAY be able to carry the service status of the tracker, e.g. work load, capacity, etc. PPSP tracker protocol MAY be able to carry the service status of the tracker, e.g. work load, capacity, etc.

5. PPSP Peer Protocol Requirements PPSP peer protocol MUST be able to carry content availability of the peers. PPSP peer protocol MUST be able to carry content availability of the peers. - In order to share content, peers must be able to tell each other which pieces of content reside in which peers. PPSP peer protocol May exchange additional peer list between peers. PPSP peer protocol May exchange additional peer list between peers. - Beside the peer list obtained from the tracker, peer may need additional peers to connect with. Therefore, peer may communicate with the peers in the current peer list to obtain additional peer lists. PPSP peer protocol May carry streaming status of the peers. PPSP peer protocol May carry streaming status of the peers. - With this information, a peer can select more appropriate peers for content sharing based on some content sharing strategies and/or application requirements.

6. PPSP Error Handling and Overload Protection Requirements A tracker, when is operating close to its capacity limit, MUST be able to inform the peers about its overload status, and reject the following PPSP messages from the peers or redirect the following PPSP message to other trackers. A tracker, when is operating close to its capacity limit, MUST be able to inform the peers about its overload status, and reject the following PPSP messages from the peers or redirect the following PPSP message to other trackers.

7. PPSP Security Considerations PPSP must be able to authenticate / authorize users for access certain media in the P2P streaming system. PPSP must be able to authenticate / authorize users for access certain media in the P2P streaming system. PPSP must have mechanisms to limit potential damage caused by malfunctioning and badly behaving peers in the P2P streaming system. PPSP must have mechanisms to limit potential damage caused by malfunctioning and badly behaving peers in the P2P streaming system. PPSP should minimize the dependency on centralized servers. PPSP should minimize the dependency on centralized servers. Existing security mechanisms should be re-used as much as possible in PPSP, to avoid developing new security mechanisms. Existing security mechanisms should be re-used as much as possible in PPSP, to avoid developing new security mechanisms. More items available in the draft and to be discussed in the future. More items available in the draft and to be discussed in the future.

8. Questions & Comments