Posts tagged ‘signalling’

Diameter–SS7 IWF: Bridging the Signals between New and Old Worlds

Ohad Ramot, F5

Ohad Ramot, Principal Software Engineer, F5

F5’s Ohad Ramot explains the challenges of translating signals between a 4G network using Diameter signaling and 3G networks using legacy SS7.

It’s widely known that LTE (4G) networks are spreading rapidly and are being deployed all over the globe. However, while 4G networks are growing, 2G/3G networks still serve most of the subscribers as they have been doing successfully for the last decades, and it seems these legacy networks are here to stay for a while. This requires operators and roaming mediators (IPX) to face the challenge of maintaining and interacting with both network architectures in parallel.

4G and 2G/3G network architectures differ in many aspects. One of the major differences is the signals mechanism that enables network nodes to interact with each other for authentication, billing, subscriber profile provisioning and more. While 2G/3G signaling mechanism is based on SS7 protocol stack, 4G networks use the relatively modern Diameter protocol on top of TCP/SCTP/IP stacks. Although both signaling methods provide solution to the same set of problems, they stem from different architectures and design philosophies.


Diameter Signaling: Change Determines Survival

This post is by MK Chang, vice president, product marketing for Aicent.

This post is by MK Chang, vice president, product marketing for Aicent.

The promise of 4G LTE and its native IP packet based technology is quickly proving its value on the world telecom stage. The number of LTE network installations on a global level helps support this claim with over 400 operators in over 124 countries investing in LTE according to GSA and up to 175 networks already commercial. This is also apparent in the rising number of greenfield opportunities for data service providers helping drive growth with new services through innovative business models.

All these influence the momentum behind the explosive interest and growth of LTE networks, which in turns gives rise to the evolution of Diameter signaling and may eventually take over the critical importance of SS7 in the signaling world.


With the exponential growth of data, the mobile industry has been guardedly awaiting the impending data surge that is building from the increased adoption and expansion of data devices. The result, is the expectation for the Diameter signaling market to double this year (2013), with revenue from signaling controllers jumping to well over 900% from 2012 to 2011, according to Infonetics.

This push into Diameter signaling comes at a cost, and that cost is to the more outmoded and aging SS7 network, lessening its importance and creating a tremendous amount of turbulence in the traditional telecom wholesale world – where change determines survival.

So what are the impending factors that will impact SS7 and continue to drive the development and expansion of Diameter Signaling?

  • Improved Scalability and Management

Newer technologies, such as Diameter, are able to handle higher volumes (data) with the same or smaller physical footprint. The Diameter infrastructure simplifies network management through a singular centralised signaling architecture reducing costs (Opex) and the complexity of the core network, while allowing the network to grow incrementally to support an expanding base of data hungry mobile subscribers.

  • Long-Term Consumption

As subscriber adoption and penetration eventually levels off and starts to decline as a result of the rapid shift by global operators to LTE networks, 3G traffic will become relatively flat. This will have direct implications on operator demand for SS7 signaling services, which will gradually decelerate, equating to a decreased demand for SS7 supporting equipment.

  • VoLTE

Over the coming years, improved services, reduced capital, and operating expenses will drive operators to minimise their support for SS7 signaling at the core, as it is replaced with new and advanced services such as VoLTE, that benefit from Diameter’s ability to handle an all-IP network landscape. This transition will only quicken as IP to IP calling becomes more mainstream.

  • Competitive Landscape

The increasingly competitive telecom services market, drives carriers to focus more attention on subscriber retention by raising customer service levels and injecting new and updated services in order to build strong customer satisfaction, support, and retention (lowering churn), all while reducing costs. The injection of new services is an opportunity to offer differentiated services that increase customer spending, while improving customer satisfaction.

  • Role Of The Wholesaler

LTE roaming is predicated on the existence of an IPX. As Diameter signaling volume grows, operators may be increasingly encouraged to use the IPX as a direct bilateral method for services like inter-carrier voice as well as SS7 signaling. This might translate into a diminished role for the international carrier acting as a wholesale agent between carriers. Certainly, the overall signaling and voice market will be big enough to sustain both IPX and wholesale players, yet there is no doubt of the increasing pressure on these international wholesalers to change in order to survive. Consolidation of the wholesale international market may be an eventuality.

There is no question, the SS7 network infrastructure will continue to exist in the near term for several reasons. One being the investment costs associated with equipment and the other is supporting a legacy mobile market that despite quickly redirecting its attention to LTE (probably the fastest adoption of a new technology in mobile’s short history) will still need to support existing users while the industry transitions over the next 5 to 10 years. This is also the case for operators within countries that are just at the cusp of transitioning from 2G to 3G services and will maintain this model for some time. The future trend will continue to focus on 4G LTE networks supporting the dynamic growth of data centric devices.

To talk further with Aicent, head down to Pod 10 on the exhibition floor of the LTE World Summit, taking place on the 24th-26th June 2013, at the Amsterdam RAI, Netherlands. Click here to download a brochure for the event.

Aicent are also nominees for the Best LTE Roaming Product or Service at the LTE Awards 2013, taking place at the 25 June 2013, De Duif, Amsterdam, Netherlands.

Supply and Demand in the Wireless World

This is a guest post by Frank Yue, Technical Marketing Manager for the Service Provider vertical at F5 Networks.  Mr. Yue has over 15 years of experience building large-scale networks and working with high performance application technologies including deep packet inspection, network security and application delivery.  He is based in North Carolina and is a scuba diving instructor in his spare time. 

What happens when you build a new product or service and everyone wants to be a part of it? When demand surpasses supply, bottlenecks and delays are created, resulting in customer dissatisfaction. It is common to see lines of people waiting to get their hands on the latest hot product. Often, the infrastructure needs to be rebuilt or changes made to people’s habits to relieve the demand. Extra lanes and bypasses are added to the highway systems to meet expected rush hour requirements. Companies attempt to build and deliver sufficient quantities of product to satisfy predicted demand on the day the book or new phone is released to the consumers.

With the availability of today’s mobile Internet and the speeds that consumers can upload and download data with today’s technologies, there is an ongoing explosion in the amount of data being consumed by mobile subscribers. Mobile Internet access is becoming a standard feature as smartphone usage continues to grow. The number of mobile devices accessing the Internet is expected to pass the number of PCs in 2013. Video has become the top application being downloaded by consumers, accounting for 40 per cent of all Internet traffic.

In the meantime, infrastructure technologies continue to improve the availability and speeds at which mobile subscribers use these data services. 4G LTE networks provide the ability to download data at speeds at up to 100Mbps. Managing bandwidth through quota controls is becoming much more common. Unlimited data plans are disappearing. Even when these unlimited plans are available, there are thresholds where bandwidth management techniques are being applied.

Communications Service Providers (CSP) understand that by providing intelligence in the network that can inspect, classify and take actions based on the characteristics of the traffic and the subscriber profile, they can more effectively manage the network availability. This is possible, while providing enhanced services to premium customers at the same time. This requires an intelligent, flexible, scalable framework that will be able to provide the services required today as well as any future services which may be added later.

One aspect that is possibly being forgotten is the astronomical growth of traffic in the control plane of the LTE network. 4G LTE networks are designed to be IP-based packet switched networks for all traffic including voice communications. As a result, there are more control plane signaling messages using the Diameter protocol being sent back and forth to manage application access as well as the voice over IP (VoIP) communications. As more LTE capable devices become available and voice over LTE (VoLTE) continues to be deployed, the danger of the Diameter signaling storm is potentially greater than the growth seen on the customer data network. It is important to ensure that a scalable, highly available infrastructure is also built for the control plane.  A Diameter Routing Agent (DRA) can be implemented to help mitigate this problem.

To manage all of these services and develop a flexible dynamic environment that provides the framework for the evolving wireless network, CSPs need to implement an infrastructure that has the intelligence to identify applications, subscribers and behavioral trends; scalability to handle the subscriber and data growth; and flexibility to meet today’s requirements in addition to the requirements of the future. The demand for more applications and bandwidth is here and it is up to the wireless providers to manage the available supply through intelligent design and execution.

Strong signals from the LTE World Summit 2012

Following on from a successful LTE World Summit conference we present a guest post from Susan Becker, director product marketing for F5 Traffix.

I’d like to share a few observations while on my way home from Informa’s LTE World Summit that just concluded in Barcelona. There was a wider range of operators attending the two day event than I expected. From our customers, I know that top tier carriers in North America are rolling out LTE, some in the Far East and others in Europe. But during the show it became clear to me that in every part of the world operators are in some planning stage towards their LTE deployment.

From every continent and then some, operators are thinking about an LTE strategy. And the ones already in the more advanced stages are approaching experienced core network infrastructure vendors such as F5 Traffix to enable them to provide advanced services in this increasingly competitive market. With smart phones already a mass market commodity, the range and quality of services are utmost in their minds. Unfortunately, there was much premature hype about LTE leading people to believe that it is a simple, fast roll out.

And that has proven to be exactly the opposite. As LTE is more of an evolution and not a revolution, most operators will experience pains in LTE deployment. The questions remain as to what extent and when these pains will happen, and most importantly how much will it cost them. Will it result in significant churn or can the churn be abated with the lure of attractive services like family data plans, and selected real-time prepaid options like optimised video upon demand for postpaid subscribers?

There are many questions that revolve around the dozens of unprecedented cases that will be analysed and planned by the industry’s best network architects and engineers. One thing is for sure, that a special focus day on signalling like the one that preceded the LTE Summit this year attracting close to 200 people to sit and listen to Diameter experts, would not have happened last year. We were overwhelmed by the positive responses we received following presentations by F5 Traffix Diameter experts Ben Volkow and Peter Nas on “Approaching Diameter as the Nervous System of the Network” and “Diameter Use Cases for the Signaling Explosion”.

The word on Diameter solutions’ ability to solve, or rather to enable, all the promises of better and faster service in LTE is out there. Mentioning signalling to industry analysts covering mobile broadband today more often than not triggers a serious conversation. Even journalists without a technical background approach F5 Traffix to write on the topic of the signaling surge in LTE. We can’t take these facts for granted as they were NOT happening last year. So yes, things are changing, and definitely for the better.

New iPad: More Fuel for the Signalling Storm

Doug Suriano, CTO of Tekelec

In the third of our series of guest blog posts, Doug Suriano, CTO of Tekelec explains the need for operators to quickly get a handle on the increase in signalling on their networks.

The third-generation iPad was one of the strongest iPad debuts yet. Pre-orders sold out before a single tablet had been shipped, and predictably lines were out the door when the device hit the shelves.

As the first LTE-enabled iPad, this product will have a huge impact on North American LTE operators, and likewise for operators in markets where LTE will soon be deployed, in a way few have considered. Mobile operators face a dual threat to network performance, customer loyalty and profitability models. The first is the well-documented growth in the volume of mobile data traffic. The second is equally critical: a ‘signalling storm’ caused by the cumulative impact of connected device and application growth, personalised service plans, and an increasingly mobile subscriber base.

The Diameter signalling traffic is the new challenge

With LTE on board, the iPad 3 is more enticing that ever for HD video, over-the-top services such as Facebook and Twitter, as well as a wide variety of data-heavy consumer and business applications. However, the rise in mobile data traffic will not be operators’ primary problem. They have been aggressively addressing data capacity for years with strategies such as migration to 3G and LTE, policy control and offloading traffic to Wi-Fi.

With LTE, operators will need to handle network signalling messages. Signalling is the underlying communications that enables charging, billing, user authentication and authorisation. These essential messages support data activity over 3G and LTE networks. The impact of network signaling, however, has gone largely unreported.

The new iPad is what I consider to be the first widely available ‘iconic’ LTE device. By virtue of its popularity, features and applications, it will escalate the volume of network signaling on LTE networks to new levels. Also, as sales increase, usage will occur outside of LTE coverage spots. Each time a subscriber moves to or from an LTE coverage area, the new iPad will register on the correct network technology, introducing a new type of signaling to the tablet market.

Mobile data usage has led to an explosion in signalling traffic generated by billions of connected devices and apps. Subscribers often use multiple applications simultaneously, requiring networks to track data usage more frequently for billing purposes. In fact, one large tier one customer told us that the number of concurrent sessions per subscriber, a measure of the number of separate mobile data activities, has increased 50 per cent in the last year.

We expect that number to increase by at least another 50 per cent in the next year, due to the LTE iPad and the expected arrival of the several new LTE smartphones. These devices increase the appeal and use of the mobile Internet and expand the number of subscribers using mobile applications.

Recent network outages serve as a reminder that a rapid growth in subscribers, devices and applications is causing a ‘signaling storm’ for operators. For most operators in developed markets, signaling traffic growth is exceeding data traffic growth.

The good news is that mobile operators can manage the signalling surge by implementing equipment based on a protocol called Diameter. This is the language that the major core and control elements in the LTE network use to communicate. By routing Diameter signalling messages more intelligently and efficiently, operators can bolster network performance; improve subscribers’ quality of experience and scale for the millions of new devices that will populate their LTE networks.

The LTE World Summit is taking place on the 23-24 May 2012 CCIB, Barcelona, Spain. Click here to register your

Signalling change – The state of the LTE market today


This is the second in a series of guest blogs from significant voices in the industry with something to say about LTE. This time we hear from Ben Volkow, VP Product of Product Development for F5 Traffix.

I know this is becoming my mantra, and may therefore sound a bit repetitive but I’ll say it again. One of the main success factors of LTE roll out and services is dependent on the quality of an operator’s Diameter Signalling Solutions. Allow me to explain.

LTE devices, including smartphones, tablets, dongles, and all of the other connected devices generate an unprecedented volume of signalling, sometimes even more than 100 times the amount of signalling we are used to experiencing in legacy networks. Signalling is the network’s internal communication system, and the language that signalling “speaks” in LTE is an IP-based stream control transmission protocol called Diameter. It plays a connecting and routing function among LTE networks and inside the network between the different network nodes.

Diameter exists everywhere in the network, for example, among enabling elements for policy management and enforcement, billing and charging, authentication, mobility management, and roaming services.

LTE was designed on the drawing board as a Greenfield technology, replacing existing legacy 2G, 2.5G, and 3G networks and building new 4G networks from scratch. Keep in mind however, that in telecoms there tends to be more evolution than revolution. So, in practice, next-generation elements are deployed side-by-side with existing legacy network functionalities. This two-generation hybrid complicates the network by filling it up with a patchwork of technologies, interfaces, and protocols. And this complication—referred to as network fragmentation—is extremely costly if not handled properly. Minimally, it requires connectivity between the LTE interfaces, protocols, and elements, as well as connectivity between the new and legacy components.

In addition, there is the huge task of simplifying this network spaghetti, and only a robust Diameter Signalling router can succeed here.

Now back to the LTE devices. Many are designed with power-saving mechanisms to preserve battery life. However, simply touching the device catalyzes signalling. Many consumers leave several applications open, such as mobile games and social networking sites—and this causes constant, massive signalling.

The “always-on” state of LTE devices are constantly pinging the network with signalling, creating a volume of signalling messages that are greater than ever experienced by a network.

The high level buzz around LTE speaks about an enhanced multimedia, personalised, and interactive experience. More specifically, LTE is expected to deliver advanced services and charging schemes such as family data plans, tiered data plans, video optimisation, and faster speeds of mobile data. Each one of these improvements involves complicated “back-office” support in the network.

Each LTE service comes with a complex navigation route among network elements like PCRFs (policy charging & rules function) that tells the network what level of data plan has been purchased by the subscriber. OCS (online charging system) elements are needed to serve prepaid customers, and BSS (business support systems) elements that are connected to data centres across vast geographic areas and require signalling to deliver the billing charges to the correct data centre.

In short, it is the Diameter Signalling router (more commonly known as DRA) that ensures that the correct information about the right subscriber is transmitted to the designated server in the network.

So, my take on the state of the LTE market is that we have witnessed a great beginning. And from our perspective, there are two types of service providers. The first is the service provider who plans for signalling routing and gateway solutions from the beginning, and the second is the service provider who doesn’t add it to the plan and ultimately experiences pain due to signalling surges and overloads. This second type of service provider quickly realises its mistakes and rushes to deploy Diameter routers and load balancers to ensure network reliability and maximum performance.

In both scenarios, LTE networks experience a bombardment of signalling at unprecedented levels. This signalling must be managed, or it will upset network performance significantly or bring network operations to a halt.

The LTE World Summit is taking place on the 23-24 May 2012 CCIB, Barcelona, Spain. Click here to register your interest.

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