KEEPING IT REAL

Intelligent network services and local number portability are driving the need for real-time OSSs

Today's telecommunications environment barely resembles what it was just a few years ago. New intelligent network services and applications, new service providers and new networks have increased the complexity of the environment to the point where a real-time, high-visibility operations support system is a necessity if the service provider is to offer its customers reliable, dependable and high-quality service.

During the kinder, simpler times of our industry, when the public network was dominated by in-band signaling, service providers could use network management systems to simply monitor the network's operational elements. They could tell, for example, whether a trunk line was functioning properly, and this type of information usually sufficed to keep the public network running smoothly.

But the rules changed with deregulation. Spurred by rapidly escalating demand for communication services, the competition among service providers became fierce. Exacerbating the situation, new start-up service providers entered the fray, enticing subscribers with new services and added features. Intelligent network services and local number portability added to the complexity of the industry. To deal with the industry's increasing complexity and to bring new features online, network service providers began migrating to SS7.

Within this environment, providers of signaling and intelligent network services such as Illuminet realized they had to expand their traditional nodal monitoring capabilities. This included adding real-time visibility into the content of the messages transmitted on the out-of-band signaling links within the network.

For incumbent carriers and new communication providers, reliability and a short mean time to repair can mean the difference between growing market share by gaining new subscribers or being at a competitive disadvantage in the marketplace.

Controlling the network When Illuminet started operating an SS7 network in 1991, its offices housing signal transfer points were staffed with on-site field engineers. The centralized network surveillance and control center (NSCC) was equipped with a network management system that monitored network elements and alerted the staff to certain conditions and problems when they occurred.

Over the years, Illuminet's network has grown, and many of the links are now in locations where there are no attending technicians. With the company's nodal network management system, if a condition arose that required evaluation and analysis of the SS7 messaging, the system did not provide the real-time information needed by the technicians who were troubleshooting and fixing the problem.

The original network management system simply did not trap the required SS7 information. To isolate a problem condition, Illuminet frequently had to dispatch technicians with protocol analyzers to several unmanned sites. Then, operations personnel in the NSCC had to coordinate the information gathering activities of these technicians to isolate the problem before it could eventually be fixed. The process was labor-intensive and time-consuming.

Illuminet needed real-time remote visibility into network links to assure the continued reliability of its network. Given the explosive growth of consumer demand and the number of new service providers entering the industry, linking into other wireline and wireless networks would only continue to increase in the future. This would further exacerbate a network management task that was becoming more complex with each passing day.

In addition to real-time remote visibility and flexibility, Illuminet required an OSS that would provide protocol analysis, call trace, traffic monitoring and ad hoc network study capabilities. Because several customers were new to SS7 and unfamiliar with its engineering, measurements and threshholding, Illuminet needed an OSS that would bridge the gap between traditional switching and SS7 switching.

Real-time visibility Illuminet chose Agilent Technologies' acceSS7 system. The 20 technicians in the NSCC use the acceSS7 OSS daily to assist customers with their SS7 needs. An additional 20 or so individuals use the system to perform engineering research and management duties.

The OSS lets the NSCC staff follow network activity on a real-time basis. By using the system's traffic monitor module, the technicians track the amount and type of traffic flowing over each link in the network so they can identify any anomalies in traffic patterns.

The traffic monitor displays the 10 most heavily loaded links of more than 2000 links in the network. It does this with two different types of displays: One looks like a radar screen, and the other, which is called an active histogram, looks like a dynamically changing bar graph.

With the information provided by the traffic monitor, the NSCC staff can instantly see when the traffic on a certain link has exceeded its typical load. When this happens, the staff can use other modules of the OSS to evaluate the SS7 data passing through the network to determine whether a problem condition exists or whether it is just a heavy traffic period. Frequently, this information can help technicians head off potential service-related problems before they affect the quality of service.

At the link level, the system's protocol analysis module has become a critical tool for examining the SS7 messages flowing between any two elements on the network. Protocol analysis is used extensively when an interconnection or interoperability problem occurs. In many cases, technicians could not resolve this type of condition without the information provided by the protocol analysis module.

Improved efficiency Illuminet's OSS has increased the number of trouble tickets that an individual technician can resolve each day. The NSCC staff has reduced the average period of time between the receipt of a customer trouble call and isolating and resolving the problem to approximately 30 minutes. Illuminet's studies indicate that one NSCC technician now can do the work that previously required five or six people.

Furthermore, greater visibility into the network means that NSCC technicians can more effectively field questions from customers and investigate hard-to-identify problems - such as verifying looping conditions in the network - without having to involve additional resources in the process.

Because looping conditions are flagged immediately, technicians can set up a protocol analysis session through the OSS to isolate any out-of-the-ordinary conditions. Then technicians can begin to identify the probable cause of the potential problem and fix it before it affects service.

Operations improvements The real-time visibility of the OSS is used by others in the operations department as well. Whenever a new link is turned up or an existing link is changed or reconfigured, the OSS is used to validate the integrity of the link and the services traversing the link. The OSS has reduced the installation process for a new customer from weeks to hours or minutes in most cases.

Because many customers aren't familiar with SS7, they often set up a link from their switch into Illuminet's network and think that all services should work right away. When they don't, Illuminet can use the OSS to look at the link and see what's going on while talking to its customer's technician on the phone. Technicians can look at messages as they pass through the link to determine whether they are properly formatted or if the data translation is taking place correctly.

Not only is the information gathered by Illuminet's OSS critical for monitoring, analyzing and troubleshooting the network, it is also useful to other departments in the company. Billing, for example, uses the SS7 information to improve the accuracy and timeliness of customer bills.

Illuminet can collect billing information via the SS7 OSS. For example, technicians can capture originating and terminating data, compare the two and make sure that the system is collecting data on all the traffic that's traversing the network. Once the OSS has collected this information, it is automatically fed into the bill generation system.

The SS7 information from the OSS also can be used to investigate and validate billing inquiries. The end result is greater billing accuracy and more realistic customer expectations.

Another layer of complexity Before de-regulation, when the industry was certainly more homogenous, the public network was mostly concerned with point-to-point communication - that is, the network simply moved communications from point A to point B.

Since de-regulation, another layer of complexity has been introduced. To route a call from A to B, it now may have to pass through points C, D and E, which could be links into and out of other networks. OSSs with out-of-band visibility into the SS7 information passing through these transitional links are needed to cope with this added complexity.

In the not-too-distant future, voice over IP will assume a larger role in the industry, and the complexity of network management will increase again. But this time it will increase exponentially. Packetized voice communications will place even greater importance on the real-time visibility provided by the OSS. It will be incumbent upon service providers to meet this challenge.