VirtualWiFi - The Basics
In basic terms, VirtualWiFi in Windows 7 is nothing but, connecting to multiple IEEE 802.11 networks using one WiFi card.
VirtualWiFi is a project Microsoft have been working on from 2002. Not being worked on now, not event supported by Microsoft research. They have provided VirtualWiFi OID support in Windows 7.
Previously VirtualWiFi was known as MultiNet. VirtualWiFi is a wireless LAN (WLAN) card virtualization architecture i.e., single WLAN card is made to appear as multiple virtual WLAN cards, isn’t that cool? What exactly does that mean? Each of the virtual WLAN card can be configure to connect to different wireless networks. Using VirtualWiFi feature, you can connect your machine to multiple wireless networks simultaneously and that too using just one WLAN card. Yes, believe it. This feature has bought into possibility different applications which were otherwise with a single WLAN card into possibility. Some of the sample applications which are now very close to reality are,
- Using VirtualWiFi, you can play your games over a network and surf the web using a different network
- VirtualWiFi can allow you to connect only a single node of a multiple node network to the internet
- Your home network can be extended by increasing it’s access to node out of the range of the wireless access point
- Tools for fault diagnosis and recovery of Wireless networks are possible. One such tool Microsoft worked on is called Client Conduit. The basic theory is to create an ad hoc network of disconnected nodes to exchange diagnostic information. This communication is achieved by using VirtualWiFi on the connected clients. The connected clients connect to the disconnected clients over an ad hoc network created, and relay relay diagnostic information back to the backup servers. A note to make here is, the communication of connected and disconnected clients is done over an ad hoc network which means, the connected client does not need to disconnect from it’s own network.
- Another application of VirtualWiFi is increasing capacity of wireless ad hoc networks. Using orthogonal channels to do this, this technique is called “Slotted Seeded Channel Hopping” (SSCH). SSCH uses virtualizes a WLAN card with a number of instances as the number of orthogonal channels present. Each of the virtual WLAN cards are then connected on a different orthogonal channel.
- Microsoft also worked on another application using Virtual WiFI named “WiFiProfiler”. WiFiProfiler was aimed to diagnose wireless problems. Basically, the connected and disconnected clients exchange information and data plane. The configuration information exchanged on the information plane is used to diagnose the problem.
VirtualWiFi was used in the Mesh Networking project. I will be discussing about Mesh Networks ahead.
Wireless Mesh Networks -
Wireless Mesh network is a wireless technology that would allow neighbors to connect their networks together. The advantages of such connectivity is, forming something called as a ‘community mesh network’. When a number of neighbors cooperate to form such a network and forward each others packets, each of them do not need to individually have an gateway. Instead they all can share faster, cost-effective Internet access via gateways that are distributed in the neighborhood. Hopping from one neighbor’s node to another, packets dynamically find a route to reach the Internet through one of the gateways. There can also collaboratively setup backup technology. Another use case is that data can be shared locally without having to move through the internet or ISP. Local community networks will allow fast and easy sharing of this cached information. With Mesh networks enables flow in network locally rather than needing external controls, etc. The mesh network sounds a very good alternative but it also has it caveats which have yet to be ironed out. Planning, security and other number of factors have yet to be designed for such networks.
Have fun.
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