You have been longing for a solution like Wi-Fi Direct but didn't even know it. Consider when you are sitting in long meeting with networking and display cables all over the place and you have content you want to share from your brand new touch screen tablet. Why can't you broadcast directly to the overhead projector? What about broadcasting from your laptop to your HDTV in your living room? Why is this not possible? Try connecting two laptops to share files - don't bother.
There is good news on the horizon because Wi-Fi Direct is here. Wi-Fi Direct is a specification that allows devices to connect to one another without the need for any type of wireless access point. The Wi-Fi Alliance has promised that Wi-Fi Direct fixes all of the things that Bluetooth was unable to do. The Wi-Fi Alliance released the Wi-Fi Direct Specification this month and we should begin seeing Wi-Fi Direct certified devices later this year.
Benefits of Wi-Fi Direct include:
- Mobility & Portability: Wi-Fi Direct doesn't require a router which changes the typical Wi-Fi connection scenario.
- Immediate Utility: It's typical for new innovations to have to grow quickly after introduction. Since there are already millions of devices that Wi-Fi Direct can connect to, the typical lifecycle of a new product release changes.
- Ease of Use: Using Direct Device Discovery and Service Discovery, Wi-Fi Direct lets users know when a connection is available. For example, if an overhead projector is Wi-Fi Direct certified, a PC wanting to connect to it could see that it is available.
- Simple Secure Connections: Security is achieved using Wi-Fi Protected Setup™ to make a connection. Using a PIN typed into both devices, it's easy to create a secure connection.
Wi-Fi Alliance History
The Wi-Fi Alliance, is a not for profit organization and was founded in 1999 by a handful of companies including Cisco, Conexant, Agere, Nokia and Symbol. Today, there are more than 350 members. Members pay $15,000 annually. The goal of the Wi-Fi Alliance was to drive adoption of the 802.11 specification for wireless access. The Wi-Fi Alliance accomplishes their goals by certifying the interoperability of products based on the wireless standard. There are more than 8,000 products that have been certified by the Wi-Fi Alliance to date. A product with the seal WI-FI CERTIFIED™ indicates that it was certified by the Wi-Fi Alliance.
Wi-Fi Direct is an extension of the Wi-Fi specification. The Wi-Fi Alliance is leveraging the more than 1 billion Wi-Fi devices in use today. In fact, one of the guiding principles of the development of Wi-Fi Direct was compatibility with legacy Wi-Fi products. The peer-to-peer specification changes the basic connection strategy. Instead of connecting to an infrastructure network like an access point, Wi-Fi Direct allows direct connection between devices.
The Wi-Fi Direct specification was originally called Wi-Fi Peer to Peer. In October 2009, the Wi-Fi Alliance announced that the specification was nearing completion and a year later, it's ready. Wi-Fi Direct competes with Bluetooth and is a software based protocol.
Wi-Fi Direct Technology
The goal of the Wi-Fi Direct technology is to extend the Wi-Fi utility as shipments of Wi-Fi products are expected to exceed 1 billion devices. Wi-Fi Direct devices support connections with existing Wi-Fi devices which gives this new technology a huge jump start. Only one of the two devices in a two-connection scenario must be Wi-Fi Direct certified. Wi-Fi has already developed a mature infrastructure that includes security, performance, ease of use and ubiquity.
The technology is implemented as a framework completely separate from the applications or even the operating system. This affords developers the opportunity to implement creative designs and be less concerned about programming for the connection. They can just leverage the connect framework available with Wi-Fi Direct.
Wi-Fi Direct Certified devices can support either an infrastructure connection or a peer to peer connection. The devices connect by forming Groups that function like Infrastructure BSS (Basic Service Set). Keep in mind that Wi-Fi Direct devices don't have full Wi-Fi functionality like you would find in Access Points. These still remain the best choice when considering multifunction requirements like you would find in a home or hotspot.
Consider a Peer to Peer Group that is made up of a legacy Wi-Fi device and a couple of Wi-Fi Direct devices. One of the Wi-Fi Direct devices has to serve as the Group owner. As part of the specification, there a multiple mandatory mechanisms that must be filled by devices in the group.
- Group Formation is the mechanism to determine which Wi-Fi Direct device is the leader of the group.
- Device Discovery is the mechanism to locate Wi-Fi Direct devices and exchange pertinent information about each device in the group.
- Client Discovery is the mechanism that enables a Wi-Fi Direct device to determine all the devices in the group.
- Power Management includes mechanisms that optimize power consumption.
Wi-Fi Direct Security
Wi-Fi Direct is extremely secure. First of all, connecting Wi-Fi Direct certified devices requires an "Active Agreement". This means that one device must request access and the other device must grant permission (in a two device connection scenario). Wi-Fi Direct certified devices support WPA2 security protection which means that only authorized devices are allowed to connect and any over the air data that is sent is encrypted using Advanced Encryption Standard (AES). Also, when Wi-Fi Direct is cross connected with a traditional wireless network, the Wi-Fi Direct groups operate in an independent security domain.
Wi-Fi Direct and Bluetooth
Bluetooth technology is similar to Wi-Fi Direct with a couple of major differences. Wi-Fi Direct claims to operate at a range of up to 200 meters which is more than double that of Bluetooth. From a bandwidth perspective, Wi-Fi Direct operates at 250 mbps. Bluetooth 3.0, the current version, only runs at a maximum of about 25 mbps. Bluetooth 4.0 is due out later this year but its major feature deals with power consumption. Experts expect the data transfer rate in Bluetooth 4.0 will be similar to Bluetooth 3.0.
The big question is whether Wi-Fi Direct will ultimately mark the end of Bluetooth. Analysts agree that while this may be a likely outcome, it won't happen anytime soon. Manufacturers are expected to build devices with both technologies for the foreseeable future.
First Wi-Fi Direct Products
The Wi-Fi Alliance formed the test suite for the certification program using these products which will become the first designated as Wi-Fi Direct Certified:
|Atheros||XSPAN dual-band 802.11n PCIe mini card (AR928x)|
|Broadcom||BCM43224 dual-band 802.11n 2x2 MIMO PCIe half mini card|
|Intel||Centrino Advanced-N 6200|
|Ralink||MIMObility 802.11n 2x2 PCIe half mini card|
|Realtek||RTL8192CE-VA4 HM92C00 PCIe mini card|
We should begin seeing Wi-Fi Direct Certified products for the Christmas shopping season. From digital cameras to wireless keyboards, get ready for a more convenient direct wireless connection.