vCloud NFV organizes distinct functions into pods. A pod is a grouping of compute, network, and storage that work together to deliver a function that the solution requires. Each pod has its own characteristics in terms of role, performance, and scale. This architectural best practice enables efficient resource management, creates a clear demarcation between resource providers and resource consumers, establishes security boundaries, and allows for the design of different levels of availability based on cluster workloads.
Architecting vCloud NFV OpenStack Edition by using well defined modules enables the CSP to accelerate deployment and reliably expand it when needed. The platform components are grouped into three distinct containments:
- Management Functions. Management functions are required to manage the NFV Infrastructure and the VNFs. MANO components, FCAPS functionality and ancillary elements such as DNS and OSS/BSS are grouped into this category.
- Edge Functions. The edge functions provide a logical networking delineation between VNFs and external networks. The edge functions process network traffic transitioning between the physical domain and the virtual domain. An example of such a function is the NSX Edge Services Gateway (ESG).
- Resource Functions. The VNFs and functions related to VNFs, such as VNF Managers, are grouped into this category
Pods can be used to streamline the NFV environment operations and delineate between different roles. For example, a cloud management team can easily operate the Management pod while a network management team is likely to oversee the Edge pod. VNFs are always deployed in the Resource pod.
Each pod is identified by its functional designation: Management pod, Edge pod, and Resource pod. The pod functions are the following:
- Management Pod. VIM components such as vCenter Server Appliance, NSX Manager, and VMware Integrated OpenStack are hosted in this pod. The plethora of FCAPS components, which include vRealize Operations Manager, vRealize Network Insight, vRealize Log Insight, Site Recovery Manager, vSphere Replication, and vSphere Data Protection are part of this pod. Other management related components such as NFV Orchestrators run in the Management pod. OSS/BSS can be very large in sizing, which is why their placement is dependent on the system itself. Since OSS/BSS are essential for the management of the virtual network services, the Management pod is a natural location to install these.
- Edge Pod. As described in Solution Overview, the virtual network NFVI building block is based on NSX for vSphere. NSX ESG that is hosted as a virtual machine appliance in this pod, handles all connectivity to the physical domain in the architecture. Other edge functions can also be hosted in this pod based on the operator needs. The type of networking traffic that traverses the Edge pod is referred to as North-South traffic.
- Resource Pod. Virtual Network Functions (VNFs) and their managers (VNFM) are placed in the Resource pod. The VNFs then form the virtual network service.
Pods represent a functional and modular boundary that is well defined and easy to replicate. The above described functions can be grouped into pods giving rise to two possible designs. The first design deploys the three pods into three dedicated distinct pods forming the basis for the three-pod design. The second two-pod design collapses the edge and resource functions into a single Edge/Resource pod for a smaller initial footprint.
