Everyone is busily preparing for GSMA’s Mobile World Congress in Barcelona next week, the theme for which is “The Mobile Horizon”. No doubt many operator discussions will focus on what’s next in LTE networks, and there most certainly will be an endless stream of “cloud” announcements.

These are exciting developments for the industry that hold great promise for better overall delivery (leading to improved customer satisfaction) at a reduced cost, but there is a cautionary tale in the background: you can’t scale your network through LTE upgrades or ‘cloud’ virtualization alone; your signaling environment has to be equally robust.

To understand this better, let’s unpack the market and network dynamics that got us to this point. As consumers rapidly adopt mobile devices and applications as part of their immersion into a digital lifestyle, the demand for bandwidth becomes outsized, leading to traffic chokepoints, even on important traffic. Soon everyone is unhappy.

In an effort to remedy this problem, operators have adopted strategies such as WiFi offload and creative offer packaging and pricing. These are good “holding actions,” but are not sufficient in the long term. Operators know this and are deploying LTE network capabilities in the hopes of being able to better serve these same demanding consumers with a more cost-effective (and eventually all-IP) network.

Finally, there is a great flurry of data center activity to put everything in a cloud environment for on-demand access to resources.

Likewise, software-defined networking (SDN) holds promise as a means to virtualize network resources in ways that will serve these varying levels of demand in the most dynamic, low-cost ways.

All of these are useful tactics, but they don’t really get the whole job done.

Recall that at the highest levels, SDN separates the control plane, i.e., the orchestration of resource allocation in the data center from the “data plane”. Inside the data plane, of course, resides the actual end-user payload. But a less-often discussed component – Diameter signaling –allows the great variety of servers, gateways and other network elements to set up sessions, authorize users and enable charging for the newest and potentially most profitable services.

Cloud virtualization certainly allows the two SDN planes to operate and scale in balanced, complementary ways so that one only spends what is needed to grow the network, but still serves user demand . At the same time, signaling must be even more robust.

According to the Tekelec LTE Diameter Signaling Index™, while data demand is growing at unprecedented rates, the signaling associated with this demand is growing three times faster!

Without an adequate signaling infrastructure based on a centralized, core Diameter signaling architecture, the network continues to be constrained by the communication path between elements such as gateways, charging systems and policy engines.

So while you’re noshing on tapas at the Fira Gran Via next week, consider not just your LTE network element and cloud needs, but the Diameter signaling requirements that actually ensure these investments deliver on their promise.

In February 2012, Infonetics Research published its inaugural Diameter Signaling Control worldwide and regional market size and forecasts report, in which we reported worldwide sales totaled $8.6M in CY11. The Diameter signaling controller market is in its infancy; as we predicted, a growing number of new products have launched in the past three months, and we expect more through 2012. As with all new markets, Diameter signaling controllers will expand functionality to meet operator requirements and use cases. We forecast revenue to grow at a 106.2% CAGR through CY16, resulting in $321.3M in revenue that year.

As mobile operators migrate to all-IP networks (access to core), signaling standards are migrating from SS7 to Diameter. At its core, Diameter enables the exchange of policy information within and between network operators. Diameter has also been developed as the foundation for authentication, authorization, and accounting (AAA) functions in IP-based networks.

Diameter signaling controllers provides centralized routing, traffic management, and load balancing among Diameter and non-Diameter elements within IMS and mobile broadband networks. It also supports protocol mediation and interworking functions between carrier networks. A fully loaded Diameter signaling controller will encompass the Diameter agents, DRA, DEA, and load balancing.

The move to all-IP mobile networks is being driven by LTE, and Infonetics forecasts that the number of LTE subscribers worldwide will grow from 9.2M in CY11 to 130.2M in CY15. The escalation of subscriber growth and the amount of signaling traffic these subscribers will generate is at the heart of our Diameter signaling controller forecast model.

As LTE networks are deployed and begin to grow, a key challenge is scaling the signaling and control plane due to the increasing amount of Diameter messages passing among network elements. Several global operators have experienced significant signaling storms in their LTE networks that in some cases have resulted in network outages. The storms have been caused by growing usage of the networks, but also by architectures that allow Diameter signaling to be dealt with on a peer-to-peer basis.

The increased use of mobile broadband networks is driving the growth of Diameter signaling within and between operators. This signaling traffic in turn has hastened the need for centralized controllers that can help manage the traffic in a more efficient and scalable manner. There are a number of key drivers to consider when evaluating the future growth of Diameter signaling traffic that will require signaling controllers:

• The continued rise in smartphone adoption as prices continue to drop due to strong competition and broad availability from high-end to low-end devices
• The availability of advanced 3G and LTE services such as tiered pricing and shared data plans, which require more frequent exchanges of policy and charging information
• The increase in the number of 3G and LTE network elements, particularly related to policy and control (e.g., PCRF, HSS, OCS), that must communicate with each other
• Roaming in LTE networks and between LTE and 3G networks, as well as subscribers moving between 3GPP (LTE/HSPA) and non-3GPP networks such as WiFi

A number of vendors are clamoring to play a role in this emerging market. We expect to see Diameter signaling controllers from at least 15 vendors by the end of 2012. Not all vendors will be successful, as the market cannot support that many, but we expect the competition to spur further innovation.

Today Tekelec is the front-runner in Diameter signaling control, with a strong revenue lead in 2011, helped by key wins in North America, including Verizon Wireless for its 3G and LTE networks and MetroPCS. With its heritage in SS7 and SIGTRAN, Tekelec has been an early mover in the Diameter signaling controller space and is well positioned for the future. In our February report, we asserted that Tekelec’s ability to draw upon its installed base of legacy customers will make it a formidable competitor. Since then, Tekelec has continued to increase its customer base for its Diameter Signaling Router (DSR), announcing 15 new customers across all regions, which confirms our statement. This brings their customer base to 19 for the DSR, totaling 1.8 million messages per second across a variety of use cases including interconnection for roaming, scaling policy deployments, core routing for LTE and IMS networks, and providing subscriber locator function in an LTE architecture.

Diane Myers

Principal Analyst, VoIP and IMS

diane@infonetics.com

When we hear about signaling and the signaling storm, we instantly think about all of the negative aspects of signaling and the costs of supporting signaling traffic in the network. However, not all signaling is “bad” traffic.

Bad News First

Radio Access Network (RAN) signaling can be considered the “bad” kind of signaling. These messages are only for establishing an Internet connection so that the data itself can reach the device.

Revenues for connections themselves are very small, yet the amount of signaling messages required to establish and then release the connection is significant.

For example, when a subscriber wishes to connect to the Internet and download an email, 50 or more signaling messages traverse back and forth between the RAN and the Gateway GPRS Support Node (GGSN). Now consider a subscriber who connects to Facebook and plans on staying logged into the account all day. The service provider, though, does not maintain the Internet connection all day. Instead, the connection ends after the initial data is sent and received. The device will then reestablish the data connection seconds later, poll the Facebook server for updates, and release the connection – requiring another round of RAN signaling messages.

Let’s assume that the connection required 50 signaling messages for setup and tear down (a conservative number). At a cycle of every 2 seconds, that’s 1500 messages an hour, 36000 messages a day. Multiply this number by 10 million subscribers and we are talking about 360,000,000,000 signaling messages in a single day!

Yes, There Is “Good” Signaling

Diameter signaling traffic, on the other hand, directly correlates to operators’ increased data revenues and provides profits they would otherwise never realize. Diameter enables personalized mobile data services, including tiers, loyalty programs, quality of service (QoS) for specific applications, over-the-top (OTT) applications value-add and RAN-congestion controls.

This “good” signaling increases as service providers begin monetizing their data networks. For example, when a subscriber wishes to purchase a higher service tier, the GGSN/Packet Gateway (PGW) will send a Diameter message to the Policy Control and Rules Function (PCRF) to find out what restrictions are to be applied based on the subscriber plan. The PCRF will then send a Diameter message to the Subscriber Profile Repository (SPR) database to retrieve the subscriber’s profile (data quota, etc.) and send this data back to the PCRF. The PCRF in turn sends this information to the GGSN/PGW for enforcement. That’s around five Diameter messages to support one interaction on a tiered service plan (and this is a simple example).

Diameter is also the protocol that:

• Connects the PCRF with the Deep Packet Inspection (DPI) equipment and the other policy enforcement control points;
• Communicates policy rules to the enforcement points throughout the network: and
• Provides the connection between the PCRF and the billing and charging domains.

The Diameter traffic that results from new revenue streams is a strong contrast to its predecessor in voice and text networks, SS7. SS7 signaling was about connecting voice facilities or, in the case of wireless networks, connecting to the Home Location Register (HLR) to support roaming.

In sum, it’s easy to have a negative association with increased signaling. But when thinking about signaling and the impact it has in the core network, remember that an increase in Diameter signaling is a good thing. It is a natural byproduct of an increase in revenue generation, and hopefully will only continue to increase as operators introduce more innovative and creative mobile data plans.

Today, Tekelec announced:

A tier one U.S. operator has selected Tekelec, the mobile broadband solutions company, to provide core Diameter routing, intelligent policy traffic routing and security for its LTE network.

Tekelec’s Diameter Signaling Router (DSR) will help the operator scale the LTE network and reduce costs, generate revenues from LTE roaming services and manage Diameter signaling and data traffic.

This is the fourth U.S. LTE operator to choose a new Diameter network from Tekelec. Earlier this month, industry analysis firm Infonetics Research named Tekelec as the “front runner” of the Diameter signaling control market.

Read the full announcement here.

Operators (and their subscribers) are experiencing the impact of a data surge on their networks. Network outages caused by sudden increases in subscriber application usage due to unexpected events serve as a reminder that the rapid growth in subscribers, devices and applications is causing a ‘signaling storm.’ In some instances, signaling traffic is exceeding data traffic. This signalling storm is causing congestion and impacting the user experience.

With the migration to 3G, LTE- and IMS-based networks, the need to manage the growth in Diameter signaling has become critical to optimize the network and ease congestion in real time. Mobile data is the greatest opportunity that operators have ever seen – revenues are growing from 242 Billion in 2010 to $419 Billion by 2016 (Ovum Research, 2011). At the same time, over-the-top application and device providers continue are capturing and monetizing subscribers’ personal data and building commercial relationships with them. More than 60 percent of mobile subscribers’ time on smartphones is spent on over-the-top applications leaving operators vulnerable to potential future outages as data traffic continues to rise (KCB Mobile Internet Trends, 2011).

It’s time for operators to adopt strategies that allow them to manage traffic growth and mitigate the impact of Apps and connected devices on network signalling. Operators are addressing concerns about data capacity by migrating to LTE, offloading traffic to Wi-Fi, and deploying small cells. However, the impact of network signaling has gone largely unreported. One recent network outage prompted the operator to ask Google to reduce the amount of signalling from Android devices. Regulation of applications that require frequent updates may serve to ease signaling traffic to some extent, but it could stifle the popularity of the Apps that have become so appealing to mobile subscribers.

To effectively capture the mobile data opportunity, operators need to become service and content enablers and intelligently control their network by implementing a New Diameter Network based on the Diameter signalling protocol.  The most important components of the New Diameter Network are Diameter routing, policy and subscriber data management.  This New Diameter Network enables operators to:

• Scale to support massive levels of signaling and data traffic;
• Deliver  personalized services;
• Capturer cloud and machine-to-machine opportunities; and
• Reduce OPEX by centralizing traffic routing and load balancing.

The New Diameter Network is a foundation of a successful mobile data business. To find out more about the New Diameter Network, check out our free white paper. Also, visit us at Mobile World Congress Hall 1 Booth 1F44 to see a demo.

Doug Suriano is CTO at Tekelec.

The world is moving to IP. Everywhere. In our networks, in our homes, and in our day-to-day lives. This means everything we do is impacted somehow by IP and the Internet. As networks migrate away from Time Division Multiplexed (TDM) based networks to all IP packetized infrastructure, a world of opportunity opens up for the service provider.

When moving to IP, everything becomes packetized. When the network becomes packetized, we can send more and more intelligence through the network. Intelligence means more control over our network resources, and the very services they provide. There needs to be more than just IP for this intelligence to manifest itself and Diameter is the source of that intelligence.

Diameter is the replacement for SS7. Remember that SS7 brought intelligence into the digitized world of telephone networks and enabled revenue generating services like Free Phone (800 services in the US) and made CDMA/GSM networks possible. It is SS7, after all, that allows mobile switches to track subscribers as they roam from network to network, share their capabilities with other networks, and deliver text messaging to their devices.

But SS7 is limited to supporting TDM networks. When the network migrates to IP, a new signaling protocol is necessary to support packet services. Diameter provides much of what SS7 provides today and much more. It is Diameter that ties new Policy and Charging Rules Function (PCRF) platforms together forming a cohesive, transparent policy function network wide. This allows service providers to manage the amount of bandwidth individual subscribers are allowed to consume based on their service plan, time of day, network conditions, and even device type and application type.

This is much more than SS7 could ever deliver, but there are more advantages than just this. Diameter is also used to migrate the charging network to packet. This means the entire network can be migrated to IP, and Diameter can be used as the signaling protocol in all domains. Migrating the charging network to IP and Diameter allows service providers to eliminate costly TDM facilities for billing domains, and brings a much more flexible signaling protocol into the network.

It is flexible because the Diameter protocol is designed to allow extensions to the protocol. The IETF has defined the base function for Diameter that is mandatory for all network elements to conform to, to enable interoperability. But 3GPP has expanded the definition of the Diameter protocol to include applications network-wide.

This means vendors can also develop their own extensions to further enhance the Diameter protocol and the interactions between their products without jeopardizing interoperability with other devices. This is why Diameter is growing in popularity, and this is why it is smart to deploy Diameter now and add to the network as you grow.

Don’t wait for LTE or IMS. Implement Diameter in your network now to support your 3G services. This is smart because when you do implement LTE, you will either have to begin interconnecting Diameter elements within the network or you will have to use mediation devices to interconnect these elements, and then later phase out the mediation devices. It makes more sense to utilize the Diameter interfaces in your network today, and grow as your network grows.

This also means you can take advantage of functions such as Policy and packetizing the charging domains. All that is required is an IP backbone, and a Diameter Signaling Router (DSR). The DSR acts as a Diameter Routing Agent in your network, providing security, congestion controls, and load balancing. Check out our white paper, The Time for Diameter is Now, for more details on how you can begin reaping the benefits of Diameter today, and the role of the DSR in your network.

Today Tekelec announced that it was named as the “front runner” in the emerging Diameter signaling control market according to Infonetics Research’s first report on the space. Tekelec achieved this position with key customer wins in North America, and the report states that, “Tekelec will continue to be a formidable competitor” because of incumbency among large operators.

Infonetics Research published its findings in the new report “Diameter Signaling Control: Annual Worldwide and Regional Market Size and Forecasts.” The firm forecasts a 106% compound annual growth rate (CAGR) for the Diameter signaling market through 2016, with North America generating the most revenue of any region each year of the forecast period.

The full announcement can be found here.

The ultimate reference guide for telecom professionals in next-gen Diameter signaling is now available on your iPhone with Tekelec’s exclusive LTE/EPC Diameter protocol reference guide. You can learn about relevant LTE/EPC Diameter procedures, browse AVP information and view detailed Diameter interface description all from one App.

To download, click here.

The phenomenal success of the iPhone quickly introduced the mobile industry to a new problem: Smartphones generate a significantly higher volume of signaling traffic, which adds to network congestion and connectivity issues. The industry is working hard on multiple ways of addressing the signaling issue, including changes in smartphones themselves.

Join Tekelec for a webinar on Wednesday, Nov. 9. This webinar will explain what challenges remain and what service providers need to be doing about them. Click here to register.