DID Pool is a feature that allows you to configure DID (Direct Inward Dialing) numbers.  DID numbers can be forwarded to the system via DID gateway or specialized DID provider.


Related documentation:


Any change you make related to Rates, Routes, Destination Sets, Tariffs, DID numbers, DID Charging Groups and Routing Groups may not be applied immediately. You need to wait at least 1 minute so that the system can update its internal "cache".  For example; if you update a heavy bulk of multiple destination sets at once, you may have to wait more than 1 minute for the system to update.  Read more...



Basic Parameters:

  • DID: this is the "canonic" E.164 number that will be used by the system for billing and accounting purposes. Calls from Accounts to DID numbers should be made through a CLD that matches the number in the DID field. The Incoming DID/CLD is only for authentication of incoming traffic. Mandatory
  • DID Translation Rule: the regular expression used to translate incoming CLD numbers into canonic E.164 form. Translation Rules are important particularly for the Callback application, where the system needs to call the CLD back. The Translation Rule can be left blank in cases where the DID comes in form of E.164, or CLD already or when E.164 CLD is not important/relevant. Optional
  • Assigned to: setting that reflects the specific Account that should ring when a call comes in through the DID, the Customer that can then delegate this DID to an Account/IVR application or the IVR Application that will handle calls coming through the DID. The DID can be unassigned, in which case the system will not perform any specific processing; the calls will be subject to the regular incoming call AA procedure. Mandatory for call setup.
  • Selling Charging group: Charging group is used to charge DIDs with some additional fee.  You can create multiple DID groups, for example, local DIDs which can cost "x" fee and toll-free DIDs which can cost a higher price. When used, charging groups will affect call costs by applying surcharges. Charging groups are also useful for IVR applications. If used with IVR applications such as Calling Card, they will result in a higher end-user charge. Charges are used to debit the balance of entity specified in Assigned To or to authenticated caller in the case of IVR. Optional

Authentication Rules:

  • Type: Remote is used for the inbound calls from outside of the system, while Late is used to allow/forbid the Late DID Recognition - accepting already authenticated call via On-Net by DID name, not Incoming DID. Mandatory
  • Incoming DID/CLD: this is the number as it comes from the DID gateway or DID provider. The number might be the same as the DID, but sometimes it could be different due to the presence of local or technical prefixes. Mandatory
  • Incoming CLI: this is the number of a Caller as it comes from the DID gateway or DID provider. If specified then only the calls that match both Incoming DID/CLD AND Incoming CLI are allowed. Optional
  • CLI Translation Rule: the regular expression used to translate Incoming CLI numbers into canonic E.164 form. Translation Rules are important particularly for the Callback application, where the system needs to call the CLI back. The Translation Rule can be left blank in cases where the DID comes in form of E.164, or CLI already or when E.164 CLI is not important/relevant. Optional
  • Vendor - A Vendor entity that contains Connections to be used for call authentication. If Buying Charging Group is specified, Vendor's balance would be credited with the fees from this charging group. 
  • Connection - an entity under specified vendor that is used for call authentication. Particularly the Destination field from Connection is used to match the source address of the caller. Case source IP of the Caller does not match the address in Connection, selected DID Authentication Rule won't be matched for this call. If no Connection is specified, then all Connections under selected Vendor would be used to form a pool of allowed IP addresses to be authenticated through this Authentication Rule. Optional
  • Buying Charging group: Charging group is used to charge DIDs with some additional fee.  Unlike Selling Charging Group the fees from Buying Charging Group are used to credit the balance of selected Vendor, same as Destination Set fees. Optional

Note: by not specifying a Vendor and Connection, your switch can receive calls from any where, exposing you to SPIT (Spam over Internet Telephony)


Two ways of DID call routing if Account is tied to a DID number:
1) If On-Net Routing is set to "Default" in the Account's Routing Group, Sippy forwards incoming DID calls to the registered Account;


2) If On-Net Routing is set to "Disabled" in the Account's Routing Group, Sippy forwards incoming DID calls to the list of Vendors using the Routing Group of the Account.


Further setup of DID if assigned to an Account is done through Incoming Routing and Trunks.


  • Case - DID number assigned to account:

Forward DID #: Without this feature, an incoming call to a UA would be sent with a CLD equal to the Account ID. This feature allows the Account UA assigned with the DID to see the DID number used for the call.  Test your UA before relying on this feature, as it might not be supported by the UA.  If 'Forward DID #' is enabled, the value from the 'DID' field is forwarded.

 
Activate the Forward DID# option for an Account assigned to the DID: