Building the intelligent network at Mobile World Congress 2013: SON

SON requirements drive split between SON overlay and single-vendor SON approaches at Mobile World Congress.

One of the key enablers of the intelligent network is SON technology. The Self Optimising Network is a network that can take in information from elements, base stations, backhaul, core elements, process them and take action automatically to optimise the performance of the network.

Standalone SON companies such as Aircom, Celcite, Arieson, Actix and, until recently, Intucell (now a Cisco acquisition), provide this capability to help operators plan, design and operate networks.

Then there are the vendors who, as SON was introduced into 3GPP standards for LTE releases, started to add SON as a differentiator to their own products. This usually meant their own network elements would have SON features such as ANR (automatic neighbour relations) or load balancing across network elements.

Small cells add greatly to the requirements for SON for a number of reasons. They need to be sited much more accurately, and that siting decision needs to factor in elements such as the users in that site and their likely activity (so do you have high value users you want to provide something dedicated for, or will WiFi offload do the trick?), as well as available backhaul and power. There are also a lot more of them, so automation becomes much more of a necessity, with a quicker payback. And because there are more of them, there’s a lot more parameters to measure and assess: more neighbours and potential interference, macro-layer interaction, handover and mobility management between cells, between layers, and between technologies (2G to 3G, 3G to 4G and so on).

If there is a philosophical debate around SON, it focusses on whether SON should centralised, distributed, or a mix of both (hybrid SON). The implications of this debate became clear at Mobile World Congress. Put simply, a centralised SON engine sits somewhere in the network where it can assess data coming in from across the network, and implement decisions back out across the network. A distributed SON might place that decisioning element further out, at an aggregation point or at a base station itself. For highly time sensitive decisions, the distributed SON fits better. But an entirely distributed SON would be very expensive, so not surprisingly most people come down on the side of the hybrid SON: do the less time-sensitive big data crunching centrally and do the latency impacting stuff more locally.

So then the discussion is about who is best placed to provide SON. The independents of course claim that it is them. The reason for this is that the main switch vendors are not about to open up the inside of their switches to their competitors.

Aircom CTO Steve Bowker told The Mobile Network, “We can support Ericsson, NSN and Huawei to provide an overlay SON that is load balancing between multiple technologies. The hardest thing is working out the actual traffic and getting highly detailed accuracy is very difficult. NSN is never going to get the same data from all the vendors. Vendors will not share the data. No-one believes it [NSN’s iSON] is true multi-vendor… getting counters from the vendors when vendors are very sensitive to that.”

That view was mirrored by Barry Graham, VP Marketing at Arieso, who said, “SON needs to be multi-technology and multi-vendor. Major vendors will refuse access to another vendor. They are paranoid about people getting hands on that data. 3GPP outlines what they must share but not access to more interesting information at a higher granularity. Network operators become the broker of that information.”

Do the vendors agree? Up to a point, in fact. NSN’s Thorsten Robrecht told TMN that NSN can “do” multi-vendor SON as part of its iSON strategy because it can access the information that 3GPP defines as a requirement. But he also conceded that NSN can do things better when it is operating solely in its own environment (ie with its own equipment feeding the iSON engine). He pointed out, however, that KDDi in Japan is using NSN’s iSON for a dual-vendor, dual-technology (CDMA-LTE) SON implementation.

Cisco, which has its recently formed Intelligent Network tagline to live up to, is spending up to $500 million on Intucell (a company Aircom’s Bowker described as “arrogant” for its “black box of magic” approach to its SON product) to use Intucell as a key driver of the orchestration of its WiFi and femtocells into the overall network optimisation platform. Intucell’s acquisition, allied to Cisco’s recent Quantum optimisation launch, shows how much is at stake here for the major vendors.

Any attempt to implement SON without taking all of those customer-centric complexities into consideration is flawed

SON annoucements and launches
Aircom launched its I-VIEW SON, which it described, as you may guess, as: “a multi-technology, centralised SON solution… combining features such as network data, root cause analysis algorithms, proven automatic configuration algorithms and operating characteristics – to find, validate and implement network parameter changes.” Bowker claimed that I-VIEW has been able to improve dropped call rates by 30% and network coverage by 20%, but more importantly had reduced the time it would have taken an engineering team to achieve the same gain by 90%.

Arieso didn’t have a specific product launch but it did reinforce the complexity + cost = need for multi vendor SON message. CTO Mike Flanagan said that one recent sweep of a network had found, in one square kilomtre, 15 GSM macro cells, 7 UMTS macros, three LTE macro cells, three UMTS small cells and 20 WiFi access points provided by six different network equipment vendors. “Any attempt to implement SON without taking all of those customer-centric complexities into consideration is flawed,” he said.

Celcite said that its multi vendor SON, launched towards the end of 2012, was now deployed in a multi-vendor environment across several mobile network markets covering almost 20,000 Node Bs. 3G vendors supported across the current deployments include Ericsson, Nokia Siemens Networks (NSN), and Huawei.

Ericsson announced its SON Policy Manager, due for release later this year, a week before MWC, on the 18 February. The Policy Manager is really a sort of SON overlay that is intended to control elements like the SON Optimiser, launched at MWC 2012. Ericsson said the Policy Manager would harmonise and coordinate the behaviour of SON features across the full network scope to ensure consistency in how SON features are configured and run.

RadCOM announced QiSolve, which it said gathers data from the Radio Access Network (RAN) and Packet Core network, to interact with Policy and Charging Control and Traffic Management solutions, triggering corrective action in these network elements to automatically optimise network performance and resolve customer experience issues.

Aside from these orchestration platforms, there were SON for X type announcements. In one example, Tellabs said that its 8602 Smart Router, designed for small cell backhaul, had been equipped with SON capabilities so that a new device could get automatic device configurations and service connectivity from the Tellabs 8000 Intelligent Network Manager (INM).