PBX Call Processes
Call Flowchart
The calling party can be a trunk user, intra-office user, or moderator of a conference system or IVR process. The following information is required for initiating a call: enterprise, DN set, calling information (includes number, call source, and rights), called number, and so on. The PBX sends the call information to the number analysis module.
Call Process Description
- If a trunk user calls an intra-office user, the PBX checks whether the user has the right to call an intra-office user against the blacklist and whitelist. If the user does not have the right, the PBX releases the call; otherwise, the PBX regulates the country code and area code for the call.
- When receiving the call information, the PBX matches the calling number against the calling number discrimination list. If the calling number does not match the list, the PBX does not discriminate the calling number; otherwise, the PBX checks whether the calling number has the calling number discrimination right. If so, the PBX changes the calling and called information; if not, the PBX releases the call.
- The PBX then analyzes the called number prefix, and determines whether the calling party has the right to dial the called number. If the calling party has the right, the PBX performs pre-routing number change; otherwise, the PBX releases the call. If the changed number needs to be reanalyzed, the PBX sends the call to the prefix analysis module again.
- After analyzing the prefix, the PBX perform the following operations:
- For an inter-office outgoing prefix, the PBX finds the corresponding trunk according to the route bound to the prefix, performs post-routing number change, and then checks whether the calling party has the inter-office outgoing call against the blacklist and whitelist. If the calling party has the right, the call is connected; otherwise, the call is released.
- For an intra-office prefix, the PBX determines whether to accept or reject the call according to the call acceptation/rejection conditions configured by the called user. If the called user does not configure the call acceptation/rejection conditions, the PBX directly calls the intra-office user.
- For a new/supplementary service prefix, if the calling party is a trunk user, the call is released; if the calling party is not a trunk user, the PBX checks whether the calling party meets the service right and status requirements. If so, the call is connected; otherwise, the call fails.
- For a conference access prefix or IVR, the PBX connects the calling party to the conference or completes the IVR call.
Processing Method |
Description |
How to Configure |
|---|---|---|
Blacklist and whitelist |
When receiving an inter-office incoming call, the PBX checks the calling number against the blacklist and whitelist. The calls rejected by blacklist or whitelist will be released. |
For the concept and configuration method, see Configuring the Blacklist and Whitelist. |
Number regulation |
Supplement the calling number according to user customization. Regulate the called number to quickly and accurately locate the called user. |
For the concept and configuration method, see Configuring a Country Code and an Area Code. |
Calling number discrimination |
Before analyzing the called number prefix, the PBX changes the number according to the enterprise, DN set, and number of the calling party. When the calling party initiates an inter-office outgoing call, the new number is used. |
For the configuration method, see Calling Number Discrimination. |
Prefix analysis |
Prefixes include basic call prefixes, new service management prefixes, new service triggering prefixes, and IVR prefixes. The rights of a basic call prefix include Inter, Local, National-toll, and International-toll. The PBX handles the prefix dialed by the calling party only when the calling party has the rights of the prefix. |
For the configuration method, see Configuring a Call Prefix. |
Long-/short-number change |
The long number is allocated by a carrier to short-number users. Short-number users can call each other by dialing the short numbers. The inter-office users need to dial the long number to call intra-office users, and the long number is displayed when the intra-office users call inter-office users. |
For the concept and configuration method, see Configuring Long and Short Codes. |
Number mapping |
Number mapping can be configured for the users with no long numbers configured. When receiving an inter-office incoming call, the PBX maps the external line number to the private line number and analyzes the number. The PBX then locates the called party according to the obtained prefix. |
For the concept and configuration method, see Configuring Number Mapping. |
Pre-routing number change |
This function allows the PBX to delete, modify, and insert calling and called numbers. You can configure whether to perform reanalysis and play reanalysis dial tone. |
For the concept and configuration method, see Configuring a Pre-routing Number Change Plan. |
Route selection |
The PBX associates the prefixes to routes, and find routes for calls. If a route selection policy is configured, the PBX selects routes according to the policy. |
For the concept and configuration method, see Configuring Intelligent Routing. |
Post-routing number change |
The PBX changes calling and called numbers according to prefixes and trunk groups. |
For the concept and configuration method, see Configuring a Post-routing Number Change Plan. |
Selective call acceptation/rejection |
After a call acceptation/rejection list is configured, the PBX determines whether to accept or release the call according to the list. |
For the concept and configuration method, see Configuring SCA and Configuring SCR. |