Think of network functions virtualization (NFV) and you're likely to think of monolithic hardware boxes being replaced with software running on virtual machines (VMs) in multiple locations, bringing down costs, increasing flexibility and agility and speeding time to market for new services. Among the functions ripe for virtualization is test and measurement (T&M).

It's certainly true that NFV is shaking up this market and significantly blurring the lines between service assurance and T&M, replacing old testing processes with a DevOps approach and seeing some new players entering the market, for instance with open source traffic simulators.

You might think that the days would be numbered for the dedicated hardware test device, operated by an engineer in a van driving to a specific location to run a specific test according to a set routine -- but this is far from the case. It's true that virtual active and passive probes and agents are replacing hardware-based probes at aggregation points because they can be deployed much more widely and flexibly, turned up or down as required for network monitoring and can run specific tests on demand. However, these software tools cannot do everything that hardware test devices can do.

One of the consequences of NFV is that more capability is being moved to the edge of networks -- for instance, to support virtualized customer premises equipment (vCPE) services for enterprises and cloud radio access network (RAN) in mobile networks. This is resulting in higher-capacity links between edge locations, which must be tested using tools that can emulate very high throughputs and can test synchronization down to microseconds. It's not possible to do this with virtualized software test tools. This means there is a continuing -- even growing -- need for "engineer plus hardware tool" testing as NFV gathers pace.

But that doesn’t mean that it’s business as usual for the vendors of this specialist equipment. The test tools are changing and fitting into more automated processes, deskilling the engineer and leveraging connectivity between the tool and a central lab from where tests can be automatically configured, and to where results can be instantly uploaded for analysis. Of course, test configuration and data analysis could be performed using virtualized equipment -- offline, but in near real-time. So while the hardware test tool is far from dead, it's certainly not immune from the impact of virtualization.

The latest Heavy Reading report report, "Test & Measurement for NFV," examines the approaches being taken in testing, measuring and monitoring a virtualized network and the way the vendors' offerings are changing. The focus is on traditional network T&M equipment vendors, including those that offer network-oriented service assurance solutions. The report examines blurring lines between test/measurement and service assurance and what the impact of this is on vendors and their service provider customers. The report profiles providers of T&M probes and other tools, a testing services consultancy with an NFV testing framework and a high-level service assurance solution provider that is competing with assurance platforms built by probe vendors.

— Danny Dicks, Contributing Analyst, Heavy Reading