NexTone Communications introduced a new session management solution that combines both transport and application QoS to deliver deterministic performance for real-time services over converged IP networks. The new platform includes a NEBS3-compliant, chassis-based Real-time Session Manager (RSM), which acts as a centralized policy manager and enforcement point to manage network resources and optimize call distribution, and the Multiprotocol Session Controller (MSC), enhanced with microflow management capabilities to work with MPLS routers to enforce QoS policies across the network edge.
NexTone said that softswitch vendors have architected their products to replace TDM voice switches and are very focused on bridging between TDM and VoIP. Meanwhile, MPLS routers are being built to provide deterministic IP transport but are not architected to process computationally-intensive real-time signaling and media transcoding. Other session border controller vendors focus on security for real-time services. NexTone said its approach is to provide the integration of transport (MPLS) and application-specific QoS (session intelligence). For instance, the IP Multimedia System (IMS) architecture enables transport and application resources, such as media servers, to be shared across multiple services and multiple access types. NexTone said it can provide the enforcement point for centralized QoS/SLA management, traffic engineering, and location services to IMS networks.
NexTone's new SIP-based Real-time Session Manager (RSM) sits in the core network and serves as a centralized policy manager and enforcement point across the signaling plane. The RSM uses dynamic session information to manage network resources (such as feature servers, media gateways, and edge devices). It selects optimum call destination and load balances high-value resources. The RSM is a modular system that can scale to support up to 200,000 simultaneous sessions in its 8U expandable chassis. The system includes three independent modules: the Location Services Module (LSM), the Traffic Engineering Module (TEM), and the Route Engine Module (REM). The LSM serves as a SIP registrar and repository for route policy and endpoint information. The TEM provides centralized SLA policy enforcement and acts as an application service broker. Using dynamic session information, the TEM manages the traffic flow between feature servers, media gateways, and other application devices and can allocate resources in advance per application. The TEM also acts as an aggregation point for Call Detail Record (CDR) data for billing purposes. The REM is an optional module that functions as a stateful SIP proxy to provide routing services. Future modules are planned to incorporate the capabilities of the NexTone NPX and SBC for maximum flexibility in session control and management.
The RSM works in conjunction with NexTone's Multiprotocol Session Controller (MSC), which enforces separate call-admission policies on an entire network, subnet, trunk group, device group, single device, or individual port within a device and/or per subscriber. The MSC controls the rate of bandwidth usage, call rate, and call capacity at network ingress and egress points. Its incremental microflow management capability adds service awareness to network by mapping individual real-time sessions to granular network flows (LSPs). For maximum service reach and availability, the MSC also manages media and signaling interconnects and interworking. Using microflow management capability, the MSC can map individual real-time sessions to MPLS label-switched paths (LSPs). The MSC can enforce separate call admission policies per subscriber and/or port, device, device group, trunk group, subnet, or across the entire network. NexTone said its carrier-class MSC can scale from 500 to more than 30,000 sessions for both media and signaling.
NexTone said it is working to promote a Media Services Control Protocol (MSCP) within the IETF.
Such a protocol would serve to separate signaling and media. Within this architecture, the session controller acts as the signaling controller and the IP/MPLS router becomes a controlled entity. Real-time signaling, such as H.323 or SIP VoIP signaling, flows through the session controller, whereas the bearer RTP packets flow through the MPLS router. The MPLS router, being a bi-directional Network Address Translator (NAT), provides the topology hiding necessary at the media plane and also maps sessions to MPLS flows based on information provided by the session controller. The MPLS router also provides packet rate and packet size controls to prevent service abuse at the media layer. NexTone is also working with the Infranet Initiative to define how MPLS technology can be used in this manner.
NexTone expects its first customer shipment in March 2005. The U.S. list price for the NexTone RSM begins at $125,000. http://www.nextone.com
- In July 2004, NexTone Communications closed $10 million in Series C funding for its end-to-end session management products. NexTone's session controllers allow carriers to route, manage, and control real-time IP traffic. Since going live with its first customer twenty-four months ago, NexTone session management products have been deployed in more than 140 carrier networks worldwide and currently manage a capacity of more than 3 billion minutes of VoIP traffic per month.
- The up round was led by BCE Capital, the venture arm of Bell Canada Enterprises, and included participation from all existing investors.
NexTone is headquartered in Gaithersburg, Maryland.
