One of the most significant changes that network functions virtualization (NFV) will introduce into the CSP environment is the use of generic IT servers rather than purpose-built, dedicated hardware platforms to run network applications and services. In addition to lowering the cost of the underlying hardware, it is expected that running virtualized network functions (VNFs) on standardized servers will give CSPs greater flexibility and improved resource utilization, and potentially converge networks and IT onto common infrastructure.
In my latest report, NFV & Telco Data Center Servers: Key Considerations & Technologies, I discuss the new requirements emerging from CSPs looking to migrate network functions from proprietary, dedicated hardware platforms to standardized IT servers. The report highlights the strategies being taken by leading vendors to support CSPs' need for performance, availability and scalability, and it analyzes how cloud and telecom environments differ, with discussion on the potential impact on using common infrastructure for all services within a telco data center.
IT servers are generally designed for enterprise applications, not telecom functions. VNFs consume server hardware resources differently than everyday IT applications. Data plane-heavy functions present a particular challenge. Understanding the differences in resource requirements for various categories of applications is needed to ensure the needed performance can be achieved.
The hypervisor-managed approach introduces a performance hit, and several technologies, including SR-IOV, PCI Pass Through, and hardware and software acceleration, are being proposed to address them. ETSI believes hypervisors play a key role in creating the execution environment, so it recommends their use, rather than bare metal for most applications. Ultimately, it wants services to be cloudified so resources can be pooled, shared and dynamically allocated.
In addition, ETSI presents high-level architectural goals in the areas of portability, reliability, security and manageability, but has stopped short of publishing specifications for the hardware platform. The Open Compute Project has developed a reference architecture, but only for servers destined for cloud applications. Despite some commonalities between IT and telecom workloads, there remain enough differences that suggest that there may be good reason to keep separate platforms for different types of workloads. The distinction is less IT vs. telco, but rather based on the attributes of the workloads themselves. Having multiple platforms, however, would not preclude the ability to manage the infrastructure with common management.
— Roz Roseboro, Senior Analyst, Heavy Reading