Overview


VirtualWire  technology uses a software approach to configure cable topologies to interconnect network devices together. Network devices are physically connected to the VirtualWire switch once using Ethernet cables and transceivers that match the device port media and speed characteristics. The desired cable topology is then obtained by a remote software configuration of the Virtual Wire switch and consists of a set of Virtual Wire links. VirtualWire topology configurations can be dynamically created, saved and re-applied without any manual intervention on the physical infrastructure.


VirtualWire is implemented using transparent low-latency Ethernet forwarding between physical ports over a non-blocking any-port to any-port switching architecture. VirtualWire transparently cross bridges any standard or proprietary Ethernet protocol of any size, including these types of traffic:


  • IPv6, Q-in-Q, VN-TAG
  • Ethernet control plane traffic such as BPDU, LACP and LLDP protocol packets
  • Proprietary or experimental Ethernet fabric
  • Undersized or invalid frames


Network devices interconnected through a VirtualWire link behave as if the devices are directly connected with a single physical cable. For example, as shown in Figure 1, if the port of Device A goes down, the VirtualWire switch automatically shuts down the port facing Device B.



 

Figure 1 -  Virtual Wire Topology


In addition, a VirtualWire switch can act as an intelligent media converter, enabling Ethernet communication between devices with different port speed and media type. In the example shown in Figure 2, a VirtualWire link is created between an optical cable connecting device A and a copper cable on device B.




Figure 2 -  Virtual Wire Topology with Optical and Copper Cables