network virtualization

Network virtualization is a term for very different approaches at hardware and software level to combine network resources into logical units or to divide them up, which are - relatively - independent of the physical conditions. This often involves the implementation of sophisticated security concepts.

A common example of this is Virtual Private Networks( VPN), which create a logical communication link between two participants or two computers that uses strong encryption, creating a virtual "tunnel" for the parties through which communication can take place. Another example is software defined networking( SDN).

Network virtualization, for example, adds a logical - virtual - layer to a local area network( LAN) that decouples the user or communications client from physical realities. Both the complexity and heterogeneity of the devices are concealed in order to ensure a uniform view and administration. For reasons of better overview, administrability and higher flexibility, physical networks are divided into logical subunits by means of suitable technologies - virtualizing switches, routers, etc. - on the one hand, and on the other hand, these can also be combined into larger units across locations - depending on requirements and tasks.

Virtual Local Area Networks ( VLAN), for example, ensure flexible shared use of local networks (LAN). Here, many different defined network connections can be switched in parallel via a physical LAN. These are virtually separated from each other, so that devices in one VLAN cannot communicate with or even "see" devices in other VLANs. From the subscribers ' point of view, the VLAN behaves like a physical LAN. Depending on the technology used, VLANs can be implemented on one of the layers from 1 to 4 of the OSI protocol. This approach increases security, creates additional logical units, and generally requires significantly fewer technical components compared to implementation as different physical networks.

In an overarching sense, three components are required to implement network virtualization: access control, securing transmission paths, and enforcing security policies.