System Architecture

RTC propose a VoIP service solution built in a highly modular way, using open standards and best practices. This solution offers the scalability, reliability and price performance Service Providers might ask for.

RTC and its partners have a long and proven track record that guarantees an extremely good user experience and novel services, now and in the future. RTCs offer an extensive range of IP-based services such as IP-Telephony, two-stage-dial, chat and click-2-call. RTC propose a complete turnkey service platform that works together with VoIP enabled mobile phones, analogue terminal adapters and softphones. With this system subscribers will be able to use VoIP, presence and instant messaging to communicate over Internet with each other. They can also have a regular phone number that will allow them to make and receive PSTN calls.

Subscribers interact with the system via the phone and the web portal.
The entire service platform is built on standard commercially available hardware, mainly from HP. The benefits are very reliable hardware, high scalability and good availability on spare parts over time.

The service platform is highly modularized. The major benefit of this is that the different modules can be scaled independently, which is an important factor when building the requested system that must scale up to very high numbers of subscribers. The modular design also improves the availability of the system.

Conceptual Overview

The service platform consists of the following major modules:

• SIP Proxy
  The main entry point in the system for all SIP signaling from the subscribers. Handles user authentication and call routing. Also determines if and when a call must be sent through the Media Proxy.


• Media Proxy
  Used for calls if needed to get through NAT routers.


• Prepay PSTN Gateway
  Calls that should be rated goes through this gateway. It checks if the subscriber is allowed to make the requested call and if he has money for it and also cuts the call when time is out. The gateway is also responsible for inserting voice prompts during the different stages of the call.


• Voicemail Server
  Stores voicemail messages.


• Presence Server
  This server handles the XMPP based IM and presence functionality.


• Provisioning Server (optional)
  Handles client software remote configuring and updates.


• Rating Engine
  Used by the Prepay Gateway to rate calls, both before calls is set-up to determine max duration and afterwards to generate the CDR record with price information.


• Admin backend
  Keeps track of all subscriber data and provides it to the other modules in the system.


• Web Portal
  The public website where people can read about the services offering, prices and sign-up. Each subscriber can sign in to a secure part of the Portal to manage his own subscription, see call lists, buy additional services or top up his prepaid account.


• Admin Web
  The user interface for support staff and for managing price plans, statistics etc.


• Database
  The various databases required in the system.


• Support Systems
  Support Systems includes log server, platform and service monitoring, backup aggregation and VPN access server.

The software modules in the system match the hardware topology closely, since the hardware and software is modularized together. As seen in the above drawing much of the communication between the modules and with the subscriber uses SOAP/HTTP/HTTPS as the protocol. This allows us to use standard off-the-shelf load balancers for scaling and availability.

The SIP communication is load balanced using DNS SRV records, which allows the system to use round-robin load balancing with optionally different priority levels (loads). Since all parts of the system is redundant and load balanced, moving parts of the platform to a new location or setting up additional server sites will be as easy as adding more servers locally.

Launching services in new countries does not require any changes in the service platform. Web site needs to be localized and possibly new call tariffs in the new currency must be added. Also new local phone numbers must be inserted. However, the platform was designed to offer services in multiple countries from the beginning. Therefore there are only configuration changes needed.

Local requirements or regulations may need customization of some parts of the platform. The modular design simplifies this task. There are no needs to put up a complete platform in each new country where services are deployed.

Business Advantages

RTC Factory's unique strength is that we can provide a telephone service, which is equipment vendor neutral, based on open licensees and with high voice quality.

Proven Technology
Quality of Service
All RTC products are developed with the highest expectations on quality, reliability and availability, just as carrier grade telecom systems should be designed. To that we have added features for voice quality that is better than the PSTN.

Proven Hardware and Operating System
The RTC products are based on state of the art servers running Linux Operating systems.

Extensive Network Connectivity
PSTN interfaces
The telephony network interfaces have been part of the Interoute Communications Ltd. and Verizon Corporate Services Corp. (MCI WorldCom) from the start and features a multitude of protocols, generic or specific to operators, vendors or countries, all of which is enabled in the RTC products.

VoIP Integration
The RTC products have interfaces and patented technology for seamless integration with SIP and VoIP systems. New and existing services can easily be added to existing and Next Generation Converged Networks.

Operational Advantages
Services
All Value Added Services available for RTC VoIP today, are available on the RTC platform to enable you with a wide range of very competitive Services.

Provisioning
DeviceDirector is an automatic provisioning of services and devices. DeviceDirector gives the operator full control over the customer’s configuration, activation and logistics including wrapping and customisation of the adapters packaging.

Support
First line support is delivers as a complimentary service from 3rd part service provider. For the moment provided in Swedish and English, during 09.00 to 20.00 only.

Support
RTC provides Second line support, Carrier class support level that is 24 hours a day, 7 days a week and 365 days a year.

Service Creation
A powerful graphical development environment is available to enable you to rapidly design and deploy new services and features directly on your live system.

Turnkey Solutions
The RTC products are delivered as turnkey products or complete systems for fast and easy integration to your new or existing network/services.

Reliability and Scalability
We have chosen the best hardware and platform available from HP and Cisco to ensure outstanding reliability and scalability to provide you with the best investment possible.

Redundancy and Availability
The RTC products are hosted at PI.SE formerly Cables & Wireless, hardware and platform is connected with dedicated lines directly to Verizon and Interoute network to ensure outstanding reliability and scalability. The RTC platform is as well connected with TeliaSonera, TDC Songs and Cables & Wireless to provide you with the best connectivity possible.

Customizability
Branding
All user interfaces are built for rapid and powerful branding and customization to fit the needs and concept of our customers.

Open Interfaces
Our interfaces for billing, statistics and other system integration points are based on open standards, widely deployed in the industry. Existing relations with NetGiro, Lindorff Group, Payex (Faktab Finans & Wallit) facilitate the billing and payment process for our customers.

Product Customization
The RTC products may easily be customized and modified to fit any specific needs of our customers. It is one of the fundamental philosophies of RTC to provide our customers with tailor made networks and service systems.