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Call Control Concepts | Appendix | Web Sequence Diagrams

The following web sequence diagrams are meant to help better understand a few of TaskRouter's key call control concepts: Blind Transfer and Warm Transfer

If you want to customize any of the flows described here for your own use, you can paste the full descriptions found below each diagram into websequencediagrams.com(link takes you to an external page) and edit from there.

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Brand new to these call control concepts? We've got you covered: check out our documentation to learn more about blind call transfers and warm transfers.

Blind Transfer

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Blind Calls Transfer web sequence diagram.
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title Blind Call Transfer

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Caller->Twilio: new call

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note over Twilio, App: <not shown> create Task

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Twilio->App: Reservation request

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App->Twilio: instruction:conference

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note right of Twilio: Twilio connects agent and caller to conference

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App->Twilio: Conference hold conference.participants.customer

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App->Twilio: New Task

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note right of Twilio:

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fill in task.requested_agent or task.desired_queue.

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Ensure workflow acts on this information

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Include conference SID of existing call

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and TaskSID of original task

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end note

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App->Twilio: remove original agent leg from conference

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App->Twilio: complete original task (or move to wrap)

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note right of Twilio: Task gets assigned

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Twilio->App: Reservation request

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App->Twilio: instruction:call

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note right of Twilio: Agent answers

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Twilio->App: webhook for TwiML for answered call

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App->Twilio: <Dial><Conference>Original Task SID</Conference></Dial>

Warm Transfer

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Warm Transfer sequence diagram.
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title Warm Transfer

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Caller->Twilio: new call

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note over Twilio, App: <not shown> create Task

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Twilio->App: Reservation request

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App->Twilio: instruction:conference

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note right of Twilio: Twilio connects agent and caller to conference

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App->Twilio: Conference hold conference.participants.customer

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App->Twilio: New Task

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alt Warm Transfer to known person

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   note right of Twilio:

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   fill in task.requested_agent

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   Ensure workflow acts on this information

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   end note

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else Warm Transfer to queue

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   note right of Twilio:

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   fill in task.desired_queue.

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   Ensure workflow acts on this information

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   end note

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end

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note right of Twilio:

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For either option, include in Task:

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- conference SID of existing call

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- TaskSID of original task

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end note

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note right of Twilio: Task gets assigned

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Twilio->App: Reservation request

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App->Twilio: instruction:call

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note right of Twilio: Agent answers

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Twilio->App: webhook for TwiML for answered call

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App->Twilio: <Dial><Conference>Original Task SID</Conference></Dial>

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note over Twilio, App: Customer, Agent 1 and Agent 2 in 3-way

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App->Twilio: remove original agent leg from conference

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App->Twilio: complete original task (or move to wrap)

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note over Twilio, App: Customer and Agent 2 in 1:1