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Making Internet Phone Calls Using Skype

by Wei-Meng Lee

Voice over IP (VoIP) is a protocol that allows users to transmit voice data over an internet connection, essentially allowing you to make phone calls to someone without going through your telecom provider. There are many types of VoIP solutions, some requiring dedicated hardware such as the Cisco IP Phone (see Figure 1) and others based purely on software.

The greatest draw of VoIP is that it greatly reduces the cost of making phone calls, especially overseas calls.

Figure 1
Figure 1. Cisco IP Phone


In this article, I will walk you through a free VoIP application developed by the inventors of Kazaa--Skype. Skype is a free VoIP application that uses a peer-to-peer networking scheme to route users' calls. To maintain voice quality, Skype employs its own proprietary audio codecs for data compression. It also uses data encryption, 256-bit AES (Advanced Encryption Standard), to ensure the privacy of calls.

Skype is currently supported on the following platforms:

  • Windows
  • Mac OS X
  • Linux
  • Pocket PC

You can obtain Skype from the company's download page. After the installation, you will be prompted to register for your account, which is free (see Figure 2).

Figure 2
Figure 2. Signing up for a Skype account

The Skype application contains three tabs (see Figure 3):

  • Contacts--shows your contact list
  • Dial--shows the dialing pad for phone numbers
  • Call List--shows the calls made as well as those missed

Figure 3--thumbnail, click for full-size image
Figure 3. The Skype application--click for full-size image

Making a Test Call

The first step you take after installing Skype is to test your microphone and speaker setup. Go to the Dial tab and type in echo123 at the bottom of the application (see Figure 4). Click on the green button to dial the number. This is a test service provided by Skype to let users test their speaker and microphone. You will be greeted by a voice and then asked to record a message of up to 10 seconds, after which the message will be played back. This allows you to verify that your microphone is connected and functioning correctly.

Figure 4
Figure 4. Dialing the echo service

Tip: For best voice quality, use a headset (see Figure 5). Better still, use a Bluetooth headset (see Getting Your Bluetooth Headset to Work in XP to learn how to set one up with Windows XP). Using a stand-alone speaker with a microphone results in echoes and makes the voice call experience quite unbearable.

Figure 5
Figure 5. Use headsets with Skype for the best voice quality

Talk Is Cheap

Related Reading

Talk Is Cheap
Switching to Internet Telephones
By James E. Gaskin

Pages: 1, 2, 3, 4

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