Merge branch 'staging' of https://github.com/AgoraIO/Docs-Source into…

… 1481-service-quota-notification

# Conflicts:
#	signaling/reference/limitations.mdx

assets/images/signaling/authentication-workflow.puml

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+@startuml
+
+!include ../video-sdk/agora_skin.iuml
+
+
+box "Implemented by you"
+
+participant  "Token server" as TS
+
+participant "Your app" as APP
+
+end box
+
+
+box "Agora"
+participant "Signaling" as API
+end box
+
+group Log in to Signaling using authentication
+TS -> TS: Configure your token server using\n your App Id and App Certificate
+APP -> TS: Request an RTM token using a user Id
+TS -> TS: Validate request against internal security\n and generate a token
+TS -> APP: Return RTM token to App
+APP -> APP: Initiate the Signaling Engine using\n the App Id
+APP -> API: Log in to Signaling using\n the user Id and the RTM token
+API -> API: Validate the token
+API -> APP: Log in user, then trigger callback
+end
+
+group Join a stream channel
+APP -> TS: Request an RTC token using\n a user Id, and a stream channel name
+TS -> TS: Validate request against internal security\n and generate token
+TS -> APP: Return RTC token to App
+APP -> API: Join a stream channel using\n channel name, user Id, and the RTC token
+end
+
+group Renew token
+API -> APP: Trigger event:\n token privilege will expire
+APP -> TS: Request an RTM token using\n the user ID
+TS -> TS: Validate request against internal security\n and generate a token
+TS -> APP: Return RTM token to App
+API <- APP: Send RTM token to Signaling with a \ncall to renew token
+API -> API: Validate the token
+API -> APP: Trigger callback
+end
+
+@enduml

assets/images/signaling/cloud-proxy.puml

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+@startuml cloud-proxy
+!include ../others/agora_skin.iuml
+
+actor "User" as USR
+
+box "Implemented by you"
+actor "Admin" as ADMIN
+participant "App" as APP
+participant "Enterprise Firewall" as FIREWALL
+end box
+
+box "Provided by Agora"
+participant "Cloud Proxy" as PROXY
+participant "SD-RTN" as API
+end box
+
+ADMIN -> FIREWALL: Whitelist IP addresses and ports\n for Cloud Proxy in the firewall.
+
+USR -> APP: Open the app
+APP -> APP: Initialize the Signaling Engine
+
+group Enable cloud proxy
+APP -> APP: Call the method to enable\na Cloud Proxy connection
+APP -> FIREWALL: Request access to \n Cloud Proxy
+FIREWALL-> FIREWALL : Check whitelist to grant\n access
+FIREWALL -> PROXY: Request access to \n Cloud Proxy
+PROXY -> APP: Proxy information 
+end
+
+USR -> APP: Join a channel
+
+APP -> PROXY: Join a channel
+PROXY -> API: Ask to join a channel
+API -> PROXY: Join success
+PROXY -> APP: Join success
+APP -> PROXY: Send data stream
+PROXY <-> API: Send and receive data stream
+PROXY -> APP: Receive data stream
+
+USR -> APP: Leave a channel
+APP -> PROXY: Leave the channel
+PROXY -> API: Channel leave
+
+
+@enduml