One of the much-touted uses of Bluetooth is as a cable replacement solution. With its short range (10 meters is common, but 100 meter devices are easy to find) and limited bandwidth, Bluetooth is well suited to applications that need to transfer small amounts of data quickly and easily.
For example, you may need to quickly copy a document (or presentation slides) to a co-worker but there is no network available at the moment. In this situation, using Bluetooth is the ideal solution. Bluetooth enables you to set up an ad hoc, wireless network instantly, without the need for a network infrastructure.
In this article, I assume that you want to copy a file from one Windows XP computer to another, and that both computers are Bluetooth-enabled. Let's step through the process of setting up Bluetooth for file transfer.
Pairing Bluetooth Devices
In Bluetooth, you have the option to "pair" two devices. When you pair with a Bluetooth device, this device will be "remembered." The next time you need to use the device, you need not search for the device again.
When pairing with a device, the device requesting the pairing will need to supply a PIN code to establish the link. The other device would need the same PIN to complete the pairing process.
You can still a use Bluetooth device without pairing; you will just need to search for the device every time you need to use it.
The first step you need to perform is to pair up with the destination computer to which you want to copy the files.
|Figure 1. Searching for the destination computer|
|Figure 2. Entering a PIN code for pairing|
Your two computers are now paired up.
Once the pairing has succeeded, you will see all of the services provided by the destination computer (see Figure 3).
|Figure 3. Services provided by the destination computer|
|Figure 4. Copying files into the File Transfer folder|
|Figure 5. Requesting permission for file transfer|
|Figure 6. Setting permissions for the file transfer|
Note that if you are copying multiple files (or a folder containing multiple files), you should check either the "For the next X minutes" or "Always allow this device to access to my computer's File Transfer service" options. This is because each file that is copied requires an explicit permission, and so if you choose the "For the current task" option, the destination computer needs to give permission for each file.
Another thing to take note is the transfer speed of Bluetooth. If you are transferring a relatively big file, be prepared to wait. A 1.6MB file typically takes about 2.5 minutes, and so you need to estimate the amount of time to allocate (and set) for this transfer.
Because Bluetooth transfer is inherently slow (compared to 802.11 or Ethernet), copying a relatively large file requires some time. It is often useful to see the status of the transfer.
On the destination computer:
|Figure 7. Checking the status of a file transfer|
|Figure 8. Displaying the status of the file transfer|
|Figure 9. Configuring the File Transfer service.|
The beauty of Bluetooth is that it can really be a lifesaver when you need to transfer files quickly, especially in situations where there is no network infrastructure available. So the next time you attend a conference, be sure to bring along your Bluetooth adapter; you never know when you will need it.
Wei-Meng Lee (Microsoft MVP) http://weimenglee.blogspot.com is a technologist and founder of Developer Learning Solutions http://www.developerlearningsolutions.com, a technology company specializing in hands-on training on the latest Microsoft technologies.
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