MetaSwitch is delivering an open "packet host-remote" architecture for telephone companies seeking to migrate from legacy switching platforms. Metaswitch said its open solution is currently being adopted by independent operating companies (IOCs) including Southern Kansas Telephone (SKT), which had been serving more than 6,000 telephone customers using a legacy host-remote network before migrating to the open "packet host-remote" architecture.
MetaSwitch highlighted several unique elements to its open host/remote architecture:
- Multi-level ESA -- traditional host-remote architectures typically implement emergency standalone (ESA) switching at one level only - the monolithic "remote switch". In contrast, MetaSwitch is working with major access vendors including Occam Networks, Paradyne and Zhone Technologies to implement multiple levels of ESA, whereby remote switch nodes, CO-based line shelves / broadband loop carriers, or even remote cabinets can lose their upstream connection and retain switching functionality, including 911 calling. This is achieved through synchronization of subscriber data between the MetaSwitch Call Agent and broadband loop carriers' own ESA functions, and/or MetaSwitch's planned ESA Call Agent that will enable standalone operation for media gateways and legacy digital loop carriers.
- Openness -- including SIP, H.248 and SIGTRAN - and proven interoperability with a wide range of equipment including broadband loop carriers and next generation remotes (trunk gateways).
- Connectionless Trunking -- instead of provisioning point-to-point TDM links between a single host and multiple remote sites, service providers can simply connect all the remotes to an IP network and let the centralized Call Agent server figure out the most efficient path to route traffic between sites. Of course, point-to-point TDM trunks can still be used instead of or alongside IP, enabling seamless migration and support for individual remote sites that are not yet connected to the core IP network.
- Distributed PSTN Trunking -- PSTN connections - whether SS7 signaling links, TDM trunks (ISUP, MF or PRI) or IP trunks using SIP - can be located in any of the switching sites in the network. In combination with Emergency Standalone (ESA), this enables remote sites to fall back to local TDM or IP trunks in the event of loss of host connectivity.
- Complete Site Redundancy -- true site redundancy is provided through the use of a fully distributed architecture, with backup Call Agent servers and Media Gateways located across two or more sites. Any one switching office can be completely lost (for example, as a result of a hurricane) with no loss of service. In this architecture, the only single point of failure for a subscriber is the line termination unit.
- Scalability -- the MetaSwitch solution scales to more than 28,000 concurrent calls per chassis, with multi-node networks (multi-chassis or multi-site) of up to 500,000 subscribers. Equally importantly, the solution scales down with cost-effective 16xT1 remotes.
- Proven Packet Architecture -- the MetaSwitch Class 5 Softswitch has been shipping with native VoIP and Ethernet interfaces since mid-2002.
- Simplified Management -- since a network can be configured as a single "virtual switch", management of subscribers, signaling links and trunks is much simplified. Operators need no longer know which remote a particular subscriber is provisioned on in order to manage its service profiles. In addition, with MetaSwitch's Web Self-Care, a single web server can seamlessly provide access to all switches in the network.
