Vendor Network Architectures�Part XXXI: Mera Systems
Mera Systems is a privately held company, founded in 1989, that develops telecommunications solutions for carriers and service providers. The firm has offices in both Canada and Russia, with over 450 customer deployments in 50 countries around the world. And while Mera may not yet be a household name in North America, they lay claim to control of over 70 percent of the VoIP softswitch market in Russia and the Commonwealth of Independent States (CIS) countries, and about 4 percent market share worldwide.
Mera's product portfolio includes three key products. The first is a VoIP softswitch, called the Mera VoIP Transit Softswitch, or MVTS for short. The second is a Session Initiation Protocol (SIP) service creation and delivery platform, called SIPrise, which enables quick design and application deployment. The third is a carrier-grade Session Border Controller, called VoIPal.
A new generation of the softswitch product, called MVTS II, was announced in late May 2006. This product has a very interesting architecture, in that the MVTS II modules can be distributed across a carrier's multiple locations, which allows almost unlimited scalability and more efficient use of system resources. The architecture of the MVTS II consists of two key subsystems: the Traffic Manager, the protocol core of the system and the center of system intelligence, plus the Traffic Switch, which handles the VoIP calls under the control of the Traffic Manager and generates call session data.
The Traffic Manager is the center of the system's artificial intelligence, and implements the carrier's business logic, including routing policies, profitability monitoring and control, and billing and accounting functions. An elaborate look-ahead routing function is implemented, which can be based upon call cost (least cost routing), call quality (Quality of Service routing), call time (Time of Day or Day of Week routing), network loading at either a gateway or a particular route, or destination gateway precedence or accessibility. Over 2 million routing alternatives are supported by the system. The Traffic Manager also includes a number of flexible billing alternatives, including the capabilities to import customer accounts and rate plans, and support for a variety of billing increment types. In addition, the Traffic Manager is the center of the operational analysis and reporting for the network, which enables the carrier to keep a finger on the pulse of their network, through the use of a number of intuitive charts and graphs that visualize the statistical data derived from the network traffic.
The Traffic Switch provides three key functions: load balancing, an H.323 Gatekeeper and a SIP Registrar. It provides a single entry point into the VoIP network, distributes the traffic load between the call processing modules, and processes the registrations of user licenses. As a signaling proxy, it provides native support for both H.323 and SIP, and also translates between these two protocols and ensures interworking between various protocol variants (the age old problem that gave rise to the phrase "interoperability," translated as "my box will not communicate with your box"). The Traffic Switch also acts as a media proxy, supporting a number of codecs, including G.711, G.723.1 and G.729.
Finally, the Traffic Switch is responsible to control and configure other nodes, collecting system performance data, ensuring the survivability of the system, and distributing user licenses across the various network locations. As an example, a carrier could locate different parts of the softswitch in different Points of Presence (or PoPs), with, say, some licenses assigned to a European center, and others assigned to a center in the United States. These licenses can be shared across the entire network, with licenses transferred to Europe during their busy hours, and then transferred back to the North American center after Europe goes home for the day.
The MVTS II is specified to handle up to 50,000 concurrent calls, with a system dependability of 99.999 percent or greater. Further details on the Mera Systems architecture and products can be found at www.mera-systems.com. Our next tutorial will continue our examination of vendors' architectures.
Copyright Acknowledgement: © 2006 DigiNet ® Corporation, All Rights Reserved
Mark A. Miller, P.E. is President of DigiNet ® Corporation, a Denver-based consulting engineering firm. He is the author of many books on networking technologies, including Voice over IP Technologies, and Internet Technologies Handbook, both published by John Wiley & Sons.