Report: Mobile Operators Challenged by Service Assurance for Virtualized Networks

Posted by Mae Kowalke on Wednesday, October 05, 2016 with No comments


More code and fewer physical parts. That’s the direction the mobile telecommunications industry is headed, concludes RCR Wireless in a report (sponsored by Accedian and several other vendors) authored by Dan Meyer, Editor-in-Chief, Telecom Software, Policy, Wireless Carriers.

The report examines in depth the move away from proprietary hardware-based platforms and toward software-based solutions designed to run on standard servers, and what this means for operators as they re-architect their networks using network functions virtualization (NFV) and software-defined networking (SDN) to keep up with demand for data services.


Deployment begins now

Despite the complexity of this endeavor, some operators are already deploying new services running on virtualized platforms.

AT&T is a good example of how operators are approaching virtualization, and the benefits they hope to gain. Its aggressive SDN and NFV strategy has already allowed the carrier to reduce CapEx and OpEx, and generate more revenue.

Service assurance in a hybrid world

It should be noted that service assurance remains a top priority for operators. As such, while virtualization seems inevitable and early adopters are putting significant effort into driving NFV and SDN ecosystem development, carriers are being careful to ensure that virtualized versions of services operate just as well as, if not better, than their traditional counterparts.

Since it’s not as if carriers are wholesale jumping all their operations to virtualization in one go (even AT&T, with its heavy focus on this initiative, expects to have 75% of its network resources under virtualized control by 2020, Meyer reports—a rapid but hardly breakneck pace), the reality is they will need to support both ‘real’ (physical) and virtualized deployments in a hybrid environment that likely will be around for another decade or so.

Because NFV and SDN WAN environment deployments are arguably still in their infancy (or at least, adolescence), carriers may struggle with a dearth of guidance around how to address reliability in this hybrid environment.

That’s what motivated AT&T to launch its Enhanced Control, Orchestration, Management, and Policy (ECOMP) project. ECOMP’s purpose is to “provide automation support or service delivery, service assurance, performance management, fault management and SDN tasks,” Meyer wrote in the report. Designed to work with OpenStack, the platform is also extensible to other cloud and compute environments. 

Operators in the driver's seat

AT&T is hardly alone in emphasizing a lack of guidance from vendors, putting telecom operators in the driver’s seat of the virtualization movement. That seat isn’t exactly comfortable, noted Verizon in the report, but confidence in their driving ability will come with time, as it does with any technological shift.

Partnerships between the open source community and operators is helping to move this process along. AT&T again comes to mind here, having recently “open sourced” ECOMP with the goal of helping to mature SDN, accelerate cloud and networking ecosystem innovation, and drive industry standardization around virtualization.

The role of vendors

Meanwhile, vendors that work in the service assurance space are also coming to grips with new business models and collaboration efforts, Meyer noted.

In some cases, this shift has been met with resistance, and in any case there is a learning curve involved. Legacy vendors that don’t move fast enough in changing their existing operations risk losing business to newer players that are disrupting the market.

Competition between incumbent vendors and disruptors is a good thing for operators, though, as it is motivating positive change in the market and accelerating the types of innovation carriers need.

“Virtualization opens up a whole new can of worms, especially for mobile,” said Scott Sumner, VP of strategic marketing for Accedian, in the RCR Wireless report. “The basic problem is that there is a much larger multiplicity of endpoints that need to be monitored. Whether it’s device aggregation points or small cells, everything is multiplying in terms of density.”

Dynamic, real-time assurance is the new standard

Denser networks mean more data flow, which in turn increases the need for robust service assurance platforms—a need that’s outpacing the capabilities of legacy assurance platforms, Meyer said.  

Unlike with physical taps and probes in traditional architectures, virtualized networks involve traffic that stays inside the core running on virtualized network functions (VNFs), or a service chain that doesn’t show up in a physical wire. A new approach is needed to gain the necessary visibility into performance.

That analysis of service flow must also, in many cases, be real-time to address an increasing drive among carriers toward agility and elasticity in their operations.

Vendors are working on network slicing initiatives that could provide some help for operators, at least in terms of effectively ensuring service level agreements tied to services deployed over virtualized platforms.

VoLTE growing pains

Service assurance is a particular challenge for voice over LTE solutions, which operators are increasing being driven to develop and roll out. In the report, Meyer described how many carriers are trying to run VoLTE platforms in a similar way to over-the-top applications, bolstered by the ability to embed service deeper into network operations. Trouble is, any imperfection in VoLTE transmission directly and noticeably degrades the customer experience. VoLTE is very unforgiving.

Using a virtualized platform to support VoLTE is one way to approach moving voice traffic to data. This means voice can be deployed as an application. But again, because voice traffic is very sensitive to disruptions, this means voice sessions must be very tightly assured, which can be quite challenging to actually achieve.

On the other hand, when operators work harder to manage and optimize voice traffic for VoLTE service, they can also improve quality of experience (QoE) for data services by using network capacity more efficiently. Verizon has been working on this problem for half a decade, and after some initial faltering found success by fine-tuning the service.

High QoE for VoLTE in the real world is not an easy task, and involves a lot of network preparation before roll-out. Carriers have learned the hard way what happens when that preparation is lacking.

“A lot of networks need to be vetted and tested with VoLTE in terms of integration and other data services,” Accedian's Sumner said in the report. “It’s hard to simulate this stuff. VoLTE worked great in the lab for years, but in commercial deployments it has been a different story.”

The key to success lies in automation.

Sumner explained: “VoLTE is very difficult to handle in a physical world, and really can’t be done with humans. Automation and virtualized instrumentation makes it much easier to see where there are issues. Loss and throughput used to not be connected, but now networks are very sensitive to throughput for retransmission. Even a less than 1% loss results in a dramatic customer experience issue. Taken separately, there is not much of an issue, but together you have a train wreck.”

What lies ahead

Virtualization may pose significant challenges, but it’s no longer optional for telecom operatorsat least if they are going to be able to handle the expected traffic demand increases from Internet of Things (IoT) and 5G in coming years. 

And, while it may make things messier in the short-term, ultimately it’s a good thing that the virtualization movement is largely being driven by operators themselves, rather than vendors.

Service assurance for virtualized environments needs some work, to be sure, but it will get there.

“In another two or three years there will be a greater level of stability in the market in terms of performance and interoperability, and for carriers that means there will be more choices available,” Accedian’s Sumner predicted.


Grab your copy of “Service Assurance in an NFV and SDN World: Assuring the Virtualized Networks of the Future” from RCR Wireless and watch the companion webinar replay.