Application server is node where business logic of services such as VPBX, VPN, Call Forwarding, Unified Communication etc. is implemented. Application server provides services for end subscribers as well as corporate users. Application logic in Application server can be invoked via SIP, IT APIs (e.g. REST) and legacy telco protocols. Application server can be operated in cloud or in on premise mode.
Telecommunication Application Server
The Telecommunication Application Server supplies services developed for circuit switch network on IMS network. By this approach it stays possible to offer legacy services (Call Forwarding, Barring, CW, etc.) for 1. LTE users, 2.PSTN users after legacy PSTN switch off. Telecommunication Application Server can be extended by convergent services such as Unified Communication, integration with Webex etc.
Standalone Application Server
Provide similar services as Telecommunication Application Server, but it can be operated without IMS since it contains Registrar, Media Server, Router/Load Balancer.
VoLTE Single Voice Call continuity application
This application is must when operator starts LTE. It enables to LTE users to be reachable (continue already setup calls) even if move outside LTE coverage. The Single Radio Voice Call Continuity (SRVCC) provides an interim solution for handing over VoLTE (Voice over LTE) to 2G/3G networks.
Carrier Routing
Enable advance routing for interconnect international traffic. It allows dynamically configure routing rules based on variety of criteria. This application supersedes routing features on legacy switches that does not allow such wide and “easy to change” configuration and thus these legacy switches do not fit today business needs. Carrier routing application brings potential of additional revenue for interconnect business.
Number Translation Services
Application allows smooth realization of Free phone, UAN, PRM. Application enables different levels of configuration e.g. most advanced used by telco operator that run this service, the second one by telco operator that sell this services to end customer and the third one for end customers.
Virtual Private Network
The VPN application adds support of Virtual Private Network functionality into IMS. The main functionality is based on merging subscribers into groups (Friends and Family) with own numbering plan, definition of screening rules between them or out of group calling.
Machine 2 Machine applications
For M2M communication will be needed new applications for example similar to VPN service. The subscriber wants to group all his machines in households. It defines rules for communications, B/W list, Firewalls etc.
Instant messaging applications
The application is based on statuses of subscriber in Instant messaging client statuses, where application could do redirection/forwarding of calls according to them.
Service delivery platforms
Application stores to supply chargeable functionalities. SDPs are applicable to both consumer and business applications.