Operational Considerations for Network Functions Virtualization – Part 1

Just a few weeks back I had the pleasure to present at VMworld 2014 in San Francisco. My session “OPT2029 – Considerations for Operational Efficiency in Telco Cloud Deployments” covered various aspects around Network Functions Virtualization Infrastructure and it’s impact on existing operational models.

Why is NFV important after all? Well, let’s take a look at ETSI’s summary of the key benefits for Network Operators and their customers:

  • Reduced operator CAPEX and OPEX through reduced equipment costs and reduced power consumption
  • Reduced time-to-market to deploy new network services
  • Improved return on investment from new services
  • Greater flexibility to scale up, scale down or evolve services
  • Openness to the virtual appliance market and pure software entrants
  • Opportunities to trial and deploy new innovative services at lower risk

Now, I’d like to start with a quick overview picture around Network Functions Virtualization that I created from ETSI’s NFV overview documents:

ETSI NFV

As you can see, NFV is split up into various parts:

  • NFVI or Network Functions Virtualization Infrastructure
  • VNF or Virtual Network Function(s)
  • NFV M&O or Management and Orchestration
  • Service, VNF and Infrastructure Description
  • OSS / BSS

In this post, I’d like to focus on considerations around introducing NFVI:

ETSI NFVI

One very important thing is that you will only see most of the NFVI benefits come to live if you concentrate on as few NFV Infrastructures as possible. Each NFVI not only means fragmentation of resources but also operational complexity as each “silo” will have specifics that need to be operated in a separate way. Even though the underlying resources will most likely be consumed via API, the actual infrastructure requires operational procedures. So for the following parts, I will focus on a shared NFVI environment, not fragmented NFVIs:

Fragmented NFVI

As with most IT-related infrastructures, terminology and methodology from ITIL comes very handy to describe and differentiate the necessary processes for Service Strategy, Service Design, Service Transition and of course Service Operation. My experience with Service Operation in a virtual environment is very similar to VMware’s Cloud Operations methodology and publications around Operations Transformation. Some of the ITIL functions need to be much closer aligned than in traditional operations, e.g. Demand, Capacity, Performance, Incident, Problem and Configuration Management.

Also, in a completely shared environment, there will be a logical separation between “Tenants” and “Provider” or in our case VNF and NFVI. But this implies a new central function for taking care of NFVI holistically: a NFVI Center Of Excellence. This NFVI COE will be covered in the next part of this series.