C2W Protocol Specification

Group 1Project RES 302

Introduction Objectives Working Environment Characteristics ACK and timeout system CHECK System Packet Formats Typical Scenarios

Objectives C2W Application

A protocol to coordinate the communication between the client and the server

A simple protocol and easy to implement Security, Reliability, Compatibility

Working Environment Application Layer

Working with unreliable transportation protocol (e.g UDP)

Possibility of connection failure/interruption/

UID : User ID Uniquely allocated with the connection

ACK RID : Room ID

0: main room; 1-255: movie room MID : Message ID

Unique between server and client for: Chat message, User list, Movie list

Characteristics

ACK and timeout system

Each information message is numbered

Return ACK after successful reception

Timeout and retry in case of message loss

CHECK SystemEvery given time(Default: 1 min)

Server

Client

ClientClient

Client

Client Timeout and auto-disconnection

Normal Scenario

Check ACK

Check Request

Packet Formats 2 message types

Control MSG / Information MSG

4 packet formatsControl Message

Client Server Information Message

Client Control Message

Server Control Message

Client Information Message

Server Information Message

Typical ScenariosConnection and Disconnection

Typical Scenarios

Typical ScenariosChatting in main room and movie

roomDisplacementChatting privately with other user

Conclusion Advantage

Security, Reliability, Certainty, Compatibility

Perspective Possibility to encrypt the message

content Anticipation window

Thanks!

Do you have any questions?

Yifu Tang

Tengfei Zhai

Jiaying Huang

Botu Sun