User Story

As an end user, I want to configure different call forwarding numbers for specific conditions (busy, no answer, unreachable, always), so that I can precisely control what happens to incoming calls in each situation and ensure I never miss important calls.

Example of use

A lawyer John Smith works for a firm that uses Cloud PBX and they set up the following call forwarding behavior:

• If their office phone is unreachable (e.g., due to internet issues), calls are forwarded to their mobile number (1 212 555 2222).

• If they are already on a call, incoming calls are forwarded to their assistant’s number (1 212 555 3333).

• If they don’t answer within 25 seconds, the call is forwarded to firm receptionist number (1 212 555 4444).

• When they go on vacation, they enable the “Always Forward” option to send all calls to a colleague (1 212 555 5555).

This setup allows the lawyer to clearly define what should happen to incoming calls in different situations — without needing to change settings manually each time. It ensures that important client calls are handled promptly and reliably, no matter where the lawyer is or what device they’re using.

Business model

Any

Technology

Current Solution

PortaSwitch supports the following forwarding modes:

• Simple Forwarding – forwards all calls to one number, typically via phone UI.

• Follow-me – supports multiple numbers/SIP URIs, time-based schedules, and ring strategies.

• Forward to SIP URI – routes calls to external IP PBXs.

• Advanced Forwarding – mix of Follow-me and SIP URI.

The most used one, follow-me, activates if any of these conditions is met:

• Phone is offline/unregistered

• User is busy

• No answer in a timeout (e.g., 30 seconds)

However, the system doesn't allow defining different call forwarding numbers separately for each condition.

Stakeholders and their benefits

Who are the users / whom we bring value to?

Use Cases

Use case #1: Conditional call forwarding

Roles: End user, PortaSwitch system, account self-care portal

Preconditions: 

• Call forwarding with Follow-me mode is enabled for all users on the main product level and can be managed by end users.

• End user John Smith has a work number 1 212 555 1111.

• John has access to his account self-care portal and is authorized to configure call forwarding settings.

Use scenario #1.1 Configure call forwarding conditions

1. On Monday at 09:00 John logs into the self-care portal and navigates to the “Call Forwarding” section.

2. John sees the following call forwarding conditions available for configuration:

   • When busy

   • When no answer

   • When unreachable

   • Always

3. John defines the call forwarding conditions:

   • When busy - forward to 1 212 555 3333 (assistant)

   • When no answer - forward to 1 212 555 4444 (firm receptionist) after 25 seconds timeout

   • When unreachable - forward to 1 212 555 2222 (John's mobile)

4. John leaves “Always” condition blank and saves the configuration.

5. A confirmation message appears that the changes were successfully saved.

Use scenario #1.2 Call forwarding – busy

1. On Monday at 10:15, John is on an active call with a client, while another incoming call arrives to his work number at 10:16.

2. John's IP phone returns Busy Here, the system detects the busy call forwarding condition and forwards the second call to 1 212 555 3333 (his assistant).

3. The assistant answers the call successfully.

Use scenario #1.2 Call forwarding – no answer 

1. On Monday at 11:00, a client calls John’s work number while he is in a meeting in a conference room.

2. John's IP phone rings, but he doesn’t pick up.

3. After 25 seconds, the system detects “No answer” and forwards the call to 1 212 555 4444 (firm receptionist number).

4. The call is answered by the receptionist.

Use scenario #1.2 Call forwarding – unreachable

1. On Monday at 14:05, John’s office internet connection goes down and his IP phone becomes unregistered.

2. At 14:06, a client calls John's work number.

3. The system detects the unreachable status (device is offline) and forwards the call to 1 212 555 2222 (his mobile).

4. John answers the call on his mobile.

Use scenario #1.2 Call forwarding – always

1. On Friday at 16:30, John prepares for his vacation, so he logs into the self-care portal to change his call forwarding settings.

2. John sees his currently active call forwarding conditions, and then enters his colleague's number 1 212 555 5555 for the condition “Always”.

3. John immediately can see that other call forwarding conditions become ignored once the number for the condition "Always" is defined.

4. John saves the configuration and sees a confirmation message that the changes were successfully saved.

5. Next Monday at 09:00, a client calls John’s office number.

6. The system detects that the call forwarding condition “Always” is active and forwards the call to 1 212 555 5555, without ringing John’s phone.

7. The colleague answers the call.

Wireframes

Non-functional requirements

Peculiarities

Performance / Clustering, Geo Redundancy/ Dual-Version, Porter / Call Control API

ESPF / Monitoring