Network management was never simple, but virtualized networking means it's now even more complex. Prior to virtualization,...
data transport was straightforward: Packets were sent from a server network interface card, across a cable to a switch, and then to another switch or destination NIC. Network configurations were relatively stable. Today, virtual switches can be created and deleted in a matter of seconds.
Services that use network functions virtualization -- such as firewalls, encryption or deep packet inspection -- are executed within a server rather than in a dedicated hardware device; this adds further complexity to virtualized networking. And network-overlay standards such as Network Virtualization using Generic Routing Encapsulation and Virtual Extensible LAN, which define ways to encapsulate an application's network links to isolate them from other applications' links, add yet another layer of complexity.
What's more, problems such as outages or overloads can occur anywhere along a network path. Hardware devices can fail; virtualized interconnections or functions can become backed up when an application moves to a new processing phase.
As a result, finding the source of a problem requires visibility into the entire path -- not just physical devices, but virtual switches and functions and network overlays as well.
Virtualized networking and a unified view
Vendors have responded to these challenges by developing software that makes visible the entire network path, both virtual and physical components. Large system suppliers, among them Cisco, Hewlett Packard Enterprise (HPE), IBM and VMware, and software vendors such as BMC and CA offer their own sets of products. In addition, open source projects OpenStack and CloudStack have attracted both commercial vendors and open source developers that offer management tools for these environments.
The ability to track packets through the network is necessary, but it's not enough. With virtualization, network and application management have become tightly interdependent. When an application starts up, virtualized networking management requires creation of virtual components and allocates network paths among application virtual machines (VMs). These VMs may execute on different servers, and may move from server to server in response to shifting loads. When a VM moves, network traffic must be redirected to support the new configuration.
In the meantime, performance monitors must report whether applications are meeting service-level agreements and track server and network utilization rates. They collect statistics that show use over time so managers can spot components that are nearing limits.
Many networks include components from multiple vendors. Recognizing this fact, vendors include support for other manufacturers' products. Cisco and VMware have formed an alliance for their products. HPE's Intelligent Management System supports VMware, Microsoft and Citrix virtualization products. IBM Cloud Manager supports Microsoft and VMware plus the KVM open source virtualization platform.
Virtualized networking requires other functions beyond network and application management, including security. To that end, management tools must be able to support both physical and virtual firewalls and perform such functions as intrusion prevention, deep packet inspection and user authentication.
Technology continues to evolve. Providing a unified network view will require continually enhanced and extended management platforms.
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