Healthy VoIP Nets�Part XXIX�Network Management Architectures: Agilent Technologies
Focusing on call signaling, Agilent's NgN Analysis System is a carrier-class toolkit for fine-tuning VoIP and IMS network performance.
Agilent Technologies, Inc., headquartered in Santa Clara, California, provides bio-analytical and electronic measurement solutions to the communications, electronics, life sciences, and chemical analysis industries.
Agilent, which was spun off from the Hewlett-Packard Company, broke records for its 1999 Initial Public Offering, raising $2.1 billion in the largest IPO in Silicon Valley history. It operates in two business segments, Electronic Measurement and Bio-analytical Measurement.
The Electronic Measurement Group (EMG) provides standard and customized electronic measurement instruments and systems; monitoring, management, and optimization tools for communications networks and services; and software design tools and related services that are used in the design, development, manufacture, installation, deployment, and operation of electronics equipment and communications networks and services.
This segment markets its products and services primarily to contract manufacturers, handset manufacturers, network equipment manufacturers, and communications service providers. The company sells its products through direct sales, distributors, resellers, manufacturers representatives, telesales, and electronic commerce.
With a 60-plus-year history of invention and innovation, Agilent claims to have customers in over 110 countries, and to generate over 60 percent of its revenues outside of the United States. The companys 19,100 employees posted net revenue of $5.4 Billion in 2007.
Agilent has developed many systems to support telecommunications networks and converged environments, including protocol analyzers, network management systems based on the Simple Network Management Protocol (SNMP), and network monitors, supporting wireline, wireless and VoIP networks.
Agilents monitoring and management solution for VoIP systems is called the NgN Analysis System. It supports VoIP, Push to Talk over Cellular (PTToC) and IP Multimedia Subsystem (IMS) networks. The system is designed to improve network connectivity, quality of service, reliability, and customer satisfaction, while lowering network operational costs.
Agilient considers the NgN Analysis System to be a carrier-class product that delivers a comprehensive view of the signaling systems deployed in either circuit-switched networks, using Signaling System 7 (SS7), or within VoIP networks. It supports a large number of legacy and converged networking protocols, including SS7, Sigtran, SIP, the Media Gateway Control Protocol (MGCP), Megaco/H.248, H.323, and Q.931. In addition, the system supports vendor-specific protocols including Nortels ASPEN and Cisco Systems CAS and Q.931/RUDP. Wireless protocols, including CDMA SIP Push to Talk, Mobile IP version 4, and Radius 3G are also supported.
The NgN Analysis System can tap the signaling information at a number of key network pointsincluding access gateways, trunk gateways, and signaling gatewayswithin legacy networks, as well as media gateway controllers, softswitches, gatekeepers, and SIP proxies within converged networks.
This flexibility with connections allows the system to address four key types of VoIP and IMS network issues, including Configuration and Provisioning Issues, such as mis-provisioned networks, dial plan problems, or insufficient capacity; Call Setup Issues, including PSTN/IP network interworking, protocol interworking, or system availability; Call Quality Issues, such as voice quality; and Service Quality Issues, including network availability and performance, as measured from the customers perspectivesuch as dropped calls or mis-provisioned subscriber features.
One of the interesting capabilities of the system is its End-to-End Network Wide Signaling View, which can trace a call from a switch and then subsequently to a gateway, gateway controller, proxy server, and signaling interface, to the end subscriber gateway. This feature provides a visual description of the call flow, with information on every call that is monitored, including both calls in progress and calls that have been already terminated.
The signaling messages associated with these calls are then correlated and stored in a Call Flow Record, or CFR, which includes addressing and routing information, quality metrics such as delay and jitter, plus response codes.
Once an individual CFR has been selected within the system, it can be displayed and analyzed, including filters that can isolate particular calls for further analysis, such as calls associated with a specific called or calling number, IP address, or start and release time. The system also generates a Service Measurement Record, or SMR, for each call, which contains performance and quality of service measurements. This data can be aggregated by the service provider by customer, by network element, or by service, thus supporting service level agreements (SLAs), network performance management functions, and network planning operations.
A QoS Manage that is incorporated into the system is designed to provide a snapshot of the quality delivered from the service perspective, and can assist with the automated management of service level agreements. This feature can analyze service records by customer, network, or network element, and then automatically generate alarms when the network does not meet baseline performance thresholds. These alarms can be communicated via pager alerts, e-mails, or through SNMP trap messages that are subsequently sent to a centralized alarm management center.
Further details on the Agilent architecture and products can be found at www.aglient.com. Our next tutorial will continue our examination of vendors network management architectures.
Copyright Acknowledgement: © 2008 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.