文档介绍：基于P2P对等技术的信息服务架构
SDD Chen Duan
内容
P2P和P2P SIP技术
基于P2P体系的信息服务架构
P2P体系架构的价值定位
结论
What’s P2P and P2P SIP?
Peer-to-Peer (P2P) Architecture: An architecture in which nodes (peers) cooperate together to perform tasks. Each node has essentially equal importance and performs the same tasks within work. Additionally, municate directly with one another to perform tasks. Occasionally, nodes with better resources (such as not being behind NATs) may have a more significant role.
P2P-SIP: The use of the Session Initiation Protocol (SIP) in settings where the service of establishing and managing sessions is principally handled by a collection of intelligent endpoints, or P2PSIP peers, rather than centralized servers as in client-server SIP as currently deployed.
Application
Transport
Network
Data link
Physical
Application
Transport
Network
Data link
Physical
Application
Transport
Network
Data link
Physical
P2P work
P2P over SIP
User interface (buddy list, etc.)
SIP
ICE
RTP/RTCP
Codecs
Audio devices
DHT (Chord)
On startup
Discover
User location
Multicast REG
Peer found/
Detect NAT
REG
REG, INVITE,
MESSAGE
Signup,
Find buddies
Join
Find
Leave
On reset
Signout,
transfer
IM,
call
SIP over P2P
VoIP, Video
Presence
IM
File Transfer
TCP/IP
P2P Applications
P2P work
DHT Layer
IETF P2P-SIP: Standardization
ON
ON
SN
SN
P1
P1+P2
P3
P1
3 Protocols
P1: C/S Registrar Protocol
Registration (put)
Lookup (get)
…
Incl. authentication
P2: P2P DHT Protocol
DHT / overlay management
…
P3: P2P Signaling
SIP (in pure end-to-end mode)
Definition of proxy-less basic SIP services
…
2 Node Types
ON: Ordinary Nodes
P2P-SIP Clients
SN: Super Nodes
P2P-SIP Peers, offering resources
Peer
Client
P2P-SIP Architecture (IETF)
Example: Skype System Architecture
Skype is built for
Minimum server load
work resources
Highest scalability at lowest cost
Media relay on clients: Legal problem, Scalability issues with thin clients
User database on client