The Elisa DDI service provides the Service Providers (SP) the ability to receive calls originating from Finland via Elisa’s telecommunications network using SIP (Session Initiation Protocol). The Service is uni-directional, i.e. including only telephone traffic originating from Finland.
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Various alternatives can be used as the dial-in numbers in Elisa DDI service:
- Local telephone numbers
- Freephone Service Numbers
It is also possibly to use customer’s existing telephone numbers and Freephone Service Numbers for Elisa DDI service dial-in numbers. In that case number portability will be used.
An example of use case for the DDI service is global telephone
conference, where Elisa provides dial-in numbers for conference calls
in Finland (the conference bridge is in country X).