Networking

Internet does not work whilst Windows VPN is connected

Posted on by Imran Rashid
Reading Time: < 1 minute

Most businesses today allow their staff to connect to the office network from home, by using a VPN connection (Virtual Private Network). This allows staff to access the office network to pick up emails or documents whilst at home or at another mobile location.

Most of the time, Window VPN setups are left as default, which means that the VPN will try to use the default gateway at the company. This causes Internet issues at the users end. For example, a user connects to VPN and is able to access email and documents but not able to access the Internet until he or she disconnects from the VPN.

The way around this and depending if your VPN will continue to function, is:

1) Click the start button
2) Click Control Panel or Settings and then control panel
3) Access network connections
4) Locate the VPN connection
5) Right click the VPN connection and click properties
6) Click the networking tab
7) High light Internet Protocol (TCP/IP) click properties
8.) Click the advanced button
9) Untick use default gateway on remote network
10) Click OK and OK again
11) Reconnect your VPN or disconnect and then reconnect

The Future Of Bluetooth

Posted on by Imran Rashid
Reading Time: 2 minutes

Because it meets the basic needs of connectivity in close range, Bluetooth has a very bright future
ahead of it.  Bluetooth is actually the result of initiatives from nine leading communications and computer industry giants, including 3-COM, Sony, Lucent, IBM, Nokia, Microsoft, etc.

Since the forming of the original group, more than 1,800 manufacturers around the world have joined
the initiative.  According to reports, the Bluetooth technology is expected to be built into more than 100 million devices, with over 670 million enabled Bluetooth devices.

Resulting from the amazing success of WAP (Wireless Application Protocol), the adoption of smart phones and hand held devices, Bluetooth can easily have an amazing impact on your day to day life.  Bluetooth is one of the key technologies that can help to make the mobile information society happen, by blurring the possibilities between home, the office, and the outside world.

The seamless integration and connectivity that Bluetooth promises will make it possible to explore a wide range of interactive and highly transparent personalized services which were actually quite difficult to dream of simply because of the complexity involved with making such devices communicate with each other.

Many Bluetooth pilot products have already been rolled into the market and backed by big vendors, which is a healthy sign for the overall acceptance of the technology.  The support for Bluetooth isn’t limited to companies that develop only Bluetooth enabled products.

The applications for Bluetooth can have great impacts on other industries as well.  The adoption
of Bluetooth technology is expected to spread throughout the industry of computers. 

Unlike infrared technology, Bluetooth is used by many different wireless devices.  Bluetooth offers
exceptional quality for short range wireless, even going through walls and obstructions.  While
infrared is the biggest competitor at this time, Bluetooth far surpasses it, proving to millions that
it is the wireless communication technology of the present day and age.

In the beginning, Bluetooth started with version 1.0, then gradually moved from there.  The current version is 2.0+EDR, with another version currently in development.  The technology behind the Bluetooth specification always getting better and better, which is why it’s so popular.

In the future, you can expect the technology behind Bluetooth to get better.  Bluetooth has proven to be the wireless standard of the future, offering you wireless connectability for hundreds of different devices.  For cell phones or other forms of wireless connections, Bluetooth is the one technology that you don’t want to find yourself without.

Key Learning Points Of Bluetooth

Posted on by Imran Rashid
Reading Time: 2 minutes

Bluetooth is easily the best in wireless handheld technology.  When it comes to learning, Bluetooth
can get quite complicated.  To help you, you’ll find the key learning points of Bluetooth below:

1.  Bluetooth is an energy efficient, low overhead communication protocol that’s ideal for
interdevice communications.

2.  Unlike infrared, Bluetooth doesn’t require a line of sight.

3.  Depending on the implementation, Bluetooth can have a range of up to 100 meters.

4.  The specification of Bluetooth consists of a Foundation Profile Document and a Foundation Core
Document.

5.  The protocol stack for Bluetooth consists of core protocols, cable protocols, and even adapted
protocols.

6.  The transmitter operates around the 2.4 GHz frequency band.

7.  The data channel will change frequency, or hops, 1,600 times in a second, between the 79 allocated channels in the ISM band.

8.  Bluetooth utilizes a spread spectrumfrequency hopping RF characteristic to ensure that
independant networking operates when the other devices are in range.

9.  A piconet is formed when one or more devices open up a channel of communication.

10.  A piconet can have a master and up to seven slaves.

11.  Communication of the interdevice is based on the concepts of channels.

12.  All Bluetooth devices are capable of transmitting voice.

13.  The channel has a total capacity of 1 MB per second.

14.  There are two types of channels with Bluetooth – SCO (Synchronous Connection Oriented) and
ACL (Asynchronous Connectionless).

15.  The SCO channels are time oriented, and are therefore primarily used for transferring time
critical data such as voice.

16.  ACL channels are normally used for communicating data.

17.  Data contained in a packet can be up to 2,745 bits in length.

18.  In a single piconet, there can be up to three SCO links containing 64,000 bits a second
each.

19.  To avoid collision and timing problems, SCO links are reserved slots that are set up by
the master.

20.  The masters can support up to three SCO links with either one, two, or three slaves.

21.  The slots that aren’t reserved for SCO links can be used as ACL links.

22.   The LMP (Link Management Protocol) will handle link level security, error corrections,
and the establishment of communications links.

23.  The LMP packets will have priority over user packets that originate and form the
L2CAP layer.

24.  The L2CAP layer will ensure an acceptable quality of service.

25.  No more than one ACL link can exist at the L2CAP layer.