Too much load on the Home Subscriber Service (HSS) can lead to degraded network service. In the planning stages of a new network or an upgrade of a legacy home location register (HLR) to an HSS for IMS capabilities, it is important to select the right HSS.
Rushing to implement IP multimedia subsystem (IMS) in a voice network can put existing voice and data services at risk. For service providers looking to implement IMS and take advantage of all of its potential revenue-generating benefits, the road to IMS implementation should be taken with comprehensive planning, careful selection of equipment, and thorough analysis of existing infrastructure as well as customer needs and expectations. Without a detailed plan, you are sure to hit some potholes on the IMS highway, but avoiding them can make the difference between a successful implementation and a world of regrets.
Key considerations include:
• The overall capacity of the HSS with the HLR in terms of subscribers
• The network connectivity in terms of IP or SS7
• Does failure of the HSS function affect the HLR function, etc.
Without addressing these concerns, the upgrade can put the incumbent voice network and business at risk.
Avoid the temptation of one-stop shopping
Buying a complete product line from a single vendor may seem like a quick solution, but it will almost certainly not be the best one. This is because many of the larger providers are only focusing on top-level elements, such as the Call State Control Function (CSCF), and providing only basic HSS and Policy Decision Functionality (PDF). Unfortunately, this approach will severely limit your capability to bring more complex services online at a later date because not all vendors are experts at all parts of the IMS network. Instead, the better approach is to use best-of-breed vendors for specific elements, and then ask the major vendor to coordinate with the smaller ones.
Provide a competitive offering
One of the advantages of IMS is that it enables rapid launching of new services. However, having a “go to market” strategy with only one or two services, which are not significantly different from existing services will not drive usage. For instance, providing a standard Push-to-Talk (PTT) service will not attract customers. It has to have compelling features, such as fast access, video capability, etc. To ensure customer retention, you will also need a comprehensive line up of other services queued up for later launch.
Don’t underestimate the impact on back office systems
It may sound obvious, but you need to be able to bill for services that are ordered and used. Billing records need to be collected, collated, and matched against network usage records. Then they need to be rated and fed in to the billing system. Without careful planning and an adequate HSS, all services will have to be subscription-based, which limits revenue potential. Choosing a robust HSS will enable a billing system that can track and match subscriber’s individual services and usage in real time, allowing for a per-use billing scheme that encourages subscribers to try new services.
Keep the User Interface Simple
People will not use what they do not understand. Think about how many people have the features of three-way calling and call forwarding on their phones and never use them. IMS offers the potential for a call to start with voice, proceed to file sharing, and end in video. Without an intuitive, easy user interface, subscribers will quickly abandon or never even try the new functionality.
Plan, train, and provide ample customer service
Unfortunately, many customer care agents do not understand how to support today’s basic IP services, let alone how to support complex SIP applications enabled by IMS. Imagine a poorly trained customer care agent trying to determine why a call did not correctly switch from voice to video, or why the video was jittery and the sound was broken. It is crucial to have properly trained agents who are ready at or before launch. Remember, a bad customer service experience can turn a customer off for life.
Provide enough bandwidth
It can be a challenge to predict need and ensure that the network has sufficient bandwidth to support the new IMS-enabled services. From a customer perspective, if you cannot get an IP connection to send an e-mail or browse the Web it is frustrating, but probably not critical. However, imagine being a utility worker up a pole in a dangerous situation, needing help, and you cannot get an IP connection to use the PTT service. This can have catastrophic results. The network planning teams must pay careful attention to bandwidth and quality of service (QoS) provisioning in order to avoid this type of situation.
All in all, the potential is great for service providers to quickly launch exciting new services using IMS, and the good news is that the necessary tools to do it successfully are already available. The secret is to have a comprehensive plan, select the best infrastructure and methods, and adequately prepare for launch. Then, the road to IMS can be smoothly paved with revenue-generating opportunities.
Russ Freen co-founded Bridgewater Systems and is responsible for product planning and architectural design for the firm. For more information, please visit www.bridgewatersystems.com. (news - alerts)