End-to-End Service Assurance is Key to Successful Deployment of VNFs

Publications - January 2018
Saurabh Mathur

With the abstraction of compute, storage, and networking functions, datacenters have long been at the forefront of deploying virtualized environments to the cloud. As use cases such as on-demand bandwidth provisioning and network slicing have recently begun attracting substantial attention, telecommunications operators have likewise begun turning to virtualization as a means to reduce costs and increase the velocity of innovation.

However, traditional network and element management systems are not capable of monitoring a hybrid network that encompasses both virtualized and non-virtualized network elements. One of the key challenges in the deployment of virtualized network functions is monitoring SLAs across services that are now being delivered dynamically. In a traditional non-virtualized environment, service assurance is based primarily on monitoring physical network elements using pull-based statistics gathering. In a virtualized environment, monitoring is more complex, as the services are now delivered through VNFs, which are ephemeral in nature and may span multiple physical resources.

For a successful transition to virtualized environments, operators need to consider the following:

  • Streaming telemetry: Traditional pull-based SNMP metric collection cannot scale in a virtualized environment. Physical network elements, as well as virtual functions, need to move towards a push-based model using streaming telemetry.
  • Service delivery verification: Delivering a service in a virtualized world means spanning multiple VNFs. For example, in SD-WAN deployments, customers want to know if inbound traffic is indeed being scanned for viruses by the VNF. Flow marking and per-packet verification would be required to identify policy violations.
  • Hybrid network orchestration: Telecom networks are complex with tens of thousands of network and compute elements. As virtualization gains entry into telecom networks, managing network elements via traditional EMS won’t work. It will be essential to build management solutions that span both physical and virtual resources.

Related articles