 | Issue: | EMEA 2014 |
| Article no.: | 14 | |
| Topic: | Fundamental issues with Diameter signalling are constraining the 4G/LTE network | |
| Author: | Robin Kent | |
| Title: | Director of European Operations | |
| Organisation: | Adax | |
| PDF size: | 208KB |
About author
Robin Kent is Director of European Operations at Adax Europe. For many years, Robin held senior positions within established equipment manufacturers, software houses and integrators in the telecom, wide area network, and office automation markets. He joined Adax in 1994 to establish the Adax business unit in Europe. He has overseen the company’s successful transition from an OEM technology supplier to a customer focused provider of high quality, high performance telecommunications products to network equipment providers and VAS companies throughout EMEA and India.
Article abstract
Fundamental issues with Diameter signaling are constraining the 4G/LTE network
The problem with Diameter is not Diameter itself, but rather its underlying transport protocol. Today’s commonly available SCTP is simply not up to the task of handling tens of thousands of very active connections every second.
The LTE network is maturing quickly, but there are still fundamental problems with the basic infrastructure. Signalling is arguably the most important component in ensuring operators can run the network effectively, and provide the best possible service to their subscribers.
Full Article
4G/LTE subscription numbers are exploding. Earlier this year, Everything Everywhere (EE) announced that its 4G subscriber numbers had hit two million and with network access being rolled out on a continual basis, the ‘next generation’ network is very much here.
LTE is delivering on its promise of providing users with a quicker, more data-centric mobile broadband service, but the backbone of the network is struggling to cope, with Diameter signaling becoming the bottleneck in LTE performance.
The problem with Diameter is not Diameter itself, but rather its underlying transport protocol. Today’s commonly available SCTP is simply not up to the task of handling tens of thousands of very active connections every second. Embedded Linux SCTP may seem like the more convenient and economical (it’s free) solution but it cannot keep up with the multitude of connections and constant user activity that is the very essence of the new, flat, All-IP networks.
The solution that Adax has developed, SCTP/T, provides Diameter with thousands of robust and reliable associations; ensuring Diameter’s instant readiness and ability to carry the traffic required by the host application to any and all of its possible destinations.
Network demands render generic transport protocol ‘insufficient’
The hard truth is that the generic transport protocol that Diameter runs over, Stream Control Transmission Protocol (SCTP), is largely insufficient and just cannot cope with the specific signaling needs that the LTE network demands. Larger volumes of data transfer and consumption mean that the strain on the network is being felt at various levels, and critical, evolved signaling and transport solutions are needed to match the demands that are being placed on the network.
The emergence of new technology usually breeds other new technologies, largely by way of support, but with recent network developments and the uptake of LTE, current signaling transport technology is no longer sufficient. This is due to the data pressures that are being placed on the network and tens of thousands of connections that it now needs to handle. Transport protocols such as SCTP, in their existing form, are insufficient and operators have to address the problem that this will pose on LTE performance and find a more reliable and robust solution.
Keeping up with constantly evolving user habits
In September of last year, Oracle surmised that service providers must factor in subscriber profiles and behaviour to successfully predict traffic and signaling patterns. This is an imperative issue for operators that seek to stay ahead or at least on top of ever-changing user tendencies.
While it’s clear there are deficiencies in the standard SCTP protocol, the problem is far greater than signaling transport technology. Operators are running the very real risk of failing to keep up with their network subscribers’ habits, especially when it comes to data consumption analytics.
This isn’t a case of replacing the entire transport protocol; it’s more a case of implementing upgraded solutions that recognise the changing data consumption landscape. Unlike previous networks, operators are experiencing an unparalleled volume of simultaneous connections on the LTE network. The number of Diameter transactions is on a sharp increase and its underlying transport layer SCTP, is critical to maintaining a high level of customer experience on the network. SCTP must be enhanced to meet this demand or the benefits of LTE won’t be realised by operators or end-users.
The challenges of data analysis
A creaking SCTP infrastructure is also having a huge impact on operators’ ability to analyse data. A reliable and robust transport layer, which can cope with thousands of signaling messages, is a fundamental part of the analytics process for operators. In a sense, it is one of the primary steps in the data analytics sequence. Data has to be delivered to operators on time, accurately and reliably. Unstable signaling will have a negative effect on network behaviour and distort analytic data. A weak SCTP can lead to many issues for analytics including data delivery and poor performance metrics. Failure to transport data effectively and efficiently will result in a backlog of data items for engineers to retrieve and analyse and, in a worst case scenario, the oversight of mission critical information.
There are core elements of the LTE network infrastructure that are simply inadequate and unable to support data-centric applications and users. When it comes to data analysis, it goes far beyond simply collecting user data for marketing purposes; it’s paramount to providing a better service to subscribers. If signaling transport protocol isn’t up to the task then there is minimal communication between the network and the operator.
The transport layer is not only important in the data analysis process; it also plays a significant part in the control of data consumption and the volume of transactions. This has become especially important following the vast uptake in data-centric applications. For Instant Messaging (IM) and VoIP communication along with video content downloads and sharing, which typically causes the most strain on the network, the transport layer is a vital component for operators.
Policy management, maximising revenue and effective billing
If the transport protocol cannot cope, then it poses a very problematic challenge for operators who are trying to manage the signaling messages that are coming through from the network. Again, the issue is forward planning as operators will be unable to identify popular items of data and subsequently manage or alter policy accordingly.
LTE has opened up a number of alternative revenue channels for operators but because there are signaling deficiencies in the network, there is a high risk that service providers will miss these essential opportunities to accurately bill users accordingly.
In a Heavy Reading report, published in November, it identified that: “to maximise the revenue opportunity, operators need to personalize their service plans around specific consumer activities and behaviors such as video sharing, online gaming or live content streaming…”
This will be particularly difficult to achieve if the signaling messages are not being correctly transported. It’s true that the ability to control communications is seriously affected with inadequate transport protocols, but the power to control billing policy will also suffer because operators are effectively operating with their hands tied behind their backs. Information is not being transported correctly, and personalising their service plans will be near impossible.
Securing the next generation network
To overcome the challenges of an ageing signaling infrastructure, and to ensure reliability, operators must look at a solution that performs vigilant in-service quality monitoring along with precise detection capabilities. LTE performance is currently being affected by transport protocol that is not only inadequate, but a hindrance on the overall signaling process.
It’s not just a case of improving the reliability of signaling transport solutions, it’s also crucial that operators look at investing in transport technology that provides the necessary security for the network and its subscribers.
If there is a fault in the transport protocol, then operators are either getting mixed or incorrect messages that can compromise network security. Faulty signaling, on any level, is an invite to harmful content or unverified users to enter the network, which the operator has a depleted level of control over.
The critical importance of effective transport protocol
The LTE network is maturing quickly, but there are still fundamental problems with the basic infrastructure. Signaling is arguably the most important component in ensuring operators can run the network effectively, and provide the best possible service to their subscribers.
The transport protocol that is critical to the signaling process is insufficient in coping with the data demands that are increasingly placed on the network and this is a situation that will only worsen if the correct and suitable transport solution isn’t adopted by operators.
