Tired of paying long distance phone bills month after month? If you're like most people reading this, you've gotten spoiled by sending unlimited emails anywhere in the world without concern for its cost. But you're still paying for long distance phone calls — right? Well, things in the phone department may be changing.

A new and relatively inexpensive “Internet phone” lets you make unlimited free phone calls anywhere in the world — without a PC. Talk as long as you like . . . as often as you like . . . and it's free!

But wait! Don't rush out and throw your “analog” telephone in the trash. Not just yet. Tomorrow's “digital” Internet phones may be here today, but they're not quite ready to totally replace traditional telephones. On the other hand, you may be able to save a bundle on your long distance phone bills — given the right circumstances.

Beating the system

Back in 1996, a French startup named Aplio had the idea of creating an “Internet phone,” which would let consumers make unlimited free long distance phone calls over the Internet. The key to this capability was on emerging technology known as “Voice over Internet Protocol” (VoIP). To be successful, Aplio's Internet phones would need to be reasonably priced, easy-to-use, reliable, and deliver speech quality comparable normal phones.

The company began shipping its first Internet phones in 1998, and since that time has shipped over 120,000 units worldwide. Collectively, the devices now account for over 7 million traffic minutes on the Internet per month. Although Aplio's Internet phone, which resembles an intercom (see photo), acts like a telephone, internally it bears a closer resemblance to a desktop PC in terms of its electronic subsystems.

Aplio's Internet phones come in two models. Aplio/Phone, the company's first Internet phone, has a built in dial-up modem and is intended for homes and small businesses that lack an always-on (broadband) Internet connection. A newer model, the Aplio/PRO, substitutes a built in Ethernet LAN interface for the dial-up modem, and therefore can plug directly into the networks commonly available at larger companies as well as a growing number of ADSL and cable-modem enabled small businesses and homes.

It's like a tiny PC . . . but different

Each speakerphone-like appliance contains a tiny single-chip embedded computer that provides many of the internal functions of a desktop PC. But unlike a general purpose PC that is used for everything from word processing, to web surfing, to gaming, the Aplio Internet phone has a single, solitary purpose: free phone calls. That specialization, according to Aplio, allows their compact and relatively inexpensive Internet phones to outperform larger, more powerful, and more expensive PCs, when it comes to providing telephone-like audio communications over the Internet.

From a computer architecture point of view, Aplio's Internet phone is roughly equivalent to a desktop PC. Like a PC, it contains a central processing unit (CPU), memory, and input/output ports — and it runs on an operating system (OS). Like a PC, the device can log into the Internet and exchange digital data and sound with a remote server or computer via “TCP/IP” protocols.

But unlike most desktop PCs, the CPU isn't made by Intel (or AMD); and the OS doesn't come from Microsoft. Rather, Aplio's Internet phones are powered by lower cost (and lower power) “reduced instruction set computer” (RISC) processors. And they run an embedded version of the open source (and royalty free) Linux operating system. Also, the devices contain just 4 MB of RAM, as compared with 64-256 MB in regular PCs, and their control software loads from a 2 MB “solid state disk,” rather than the 1GB+ hard disks now common in PCs.

Another important difference between Aplio's Internet phones and PCs is their sheer simplicity: they're small, consume minimal power, are relatively inexpensive, and behave like appliances (once you configure them, that is). Those features derive from judicious selection of technologies and components, along with careful attention to human factors in designing the application software.

The result is a device with the simplicity of an appliance — one that operates more like an ordinary telephone, than like a desktop computer.

How does it compare to ordinary phones?

To maximize functionality and minimize cost, Aplio developed a unique and highly efficient internal system architecture that retains only those computer functions needed for Internet access and speech communication. Conversely, Aplio added some specialized hardware and software technologies, not normally found in PCs, that enhance the quality of IP telephony.

For example, a pair of digital signal processors (DSPs) within each phone optimizes speech compression and decompression quality. Similarly, a unique software function called “PacketPlus” monitors Internet traffic and adjusts the size and number of data packets transmitted, to continually tune the connection in much the same way that an electronic ignition improves engine performance.

The result, says Aplio, is “an experience that is very near to true telephone sound quality . . . a crisper, clearer voice quality, comparable to, or better than, digital [cellular] phones.”

How do you use it?

Here's how you make a phone call using a pair of Aplio Internet phones. There are two cases, depending on whether you and the person you are calling are using Aplio/Phone or Aplio/PRO devices.

Making a call with an Aplio/Phone

• The Aplio/Phone is installed between the telephone and the telephone line. It must be configured, according to a well documented procedure, prior to first time use. Among other things, the process stores your ISP's dial-up number, your password for ISP access, and your Aplio/Phone's unique ID.
  

  

  
  
• You dial and connect to the party you want to speak to, using a normal telephone call. As quickly as possible, you both agree to switch to the Aplio phones, and then one of you presses the device's “Aplio” button. At that point, the Aplio/Phone asks you both to hang up your (conventional) telephones.

• An automatic sequence of events now occurs. First, the two Aplio phones exchange some information with each other, such as their respective IDs for Internet connection. Next, they hang up the telephone lines on each end. Then, they each dial into their respective Internet service providers and proceed to make an Internet-based connection to each other. This process takes about a minute.

• As soon as the two phones establish an Internet connection to each other, each phone rings to indicate that the call is ready. At that point, you can talk as long as you like — using either the connected telephones or the speakerphone capability that is built into each of the devices.

  NOTE: the short initial call in the above sequence of steps, made using a normal telephone call, is subject to standard telephone charges. Aplio provides an alternate procedure, based on pre-arranged call times, which can be used to eliminate the short initial direct phone call between Aplio/Phones.

Making a call with an Aplio/PRO

• The Aplio/PRO is installed between your telephone and the telephone line. The device also plugs into an Ethernet LAN. A hub function is built in, so you can plug your computer's LAN cable into the device, and the device into the LAN. The Aplio/PRO must be configured, according to a well documented procedure, prior to first time use. Among other things, the process stores your Aplio/PRO's unique ID.

• You pick up the handset of the telephone that is connected to the Aplio/PRO, press the “Aplio” button on the Aplio/PRO, and use your telephone handset to dial the ID of the Aplio/PRO that you are calling.

• Your Aplio/PRO now proceeds to establish an Internet-based connection to the Aplio/PRO whose ID you have dialed. This process takes about 3-5 seconds.

• As soon as the Internet connection between your Aplio/PRO and the remote Aplio/PRO is established, each phone rings to indicate that the call is ready. At that point, you can talk as long as you like — using either the connected telephones or the speakerphone capability that is built into each of the devices.

But . . . it takes two to tango

One obvious disadvantage of using an Internet phone would seem to be that you can only call other Internet phones. So, for example, if you want to make free phone calls to your son or daughter at college, you need to purchase a pair of the devices. Which, of course, raises the break even point. Aplio conveniently provides an online “savings calculator” that let's you figure how much money you stand to save using an Aplio Internet phone.

Fortunately, however, the world of IP Telephony is moving fast. More and more PC's are gaining the ability to act like Internet phones. In fact, Microsoft's NetMeeting, now a standard feature of Windows, lets you hold live telephone-like voice conversations with other PC users — and, now, with Aplio Internet phone users as well. To facilitate this, Aplio recently upgraded the internal software in their Internet phones to support the H.323 Internet telephony protocol. On the other hand, a drawback of communicating with PCs, according to Aplio, is that PC-based IP Telephony is of lower quality — so calls between an Aplio Internet phone and a PC are going to be less satisfactory than calls between a pair of Aplio Internet phones.

Aplio will soon introduce a service that will allow users of its Internet phones to communicate with ordinary telephones — a network of service providers that provide a gateway between IP Telephony traffic and normal telephones. Here's how that works: servers at the service provider locations receive the IP Telephony calls and make outbound phone calls over normal phone lines, to telephone numbers within their local calling zones. As a result, Aplio Internet phone users will be able to call ordinary telephones, provided a service provider exists within the local calling area of the destination phone. But there's a catch: it's likely that such a service will be subject to nominal usage fees.

Turning up the volume

With a potential market of hundreds of millions of Internet phones, Aplio early on recognized the need to cost reduce the devices once the design was proven. Accordingly, the company developed a unique “system-on-chip” integrated circuit, the Aplio/TRIO, that contains most of the electronic functions used within the Internet phones.

The Aplio/TRIO contains three processor devices: an ARM7TDMI 32-bit RISC CPU core, plus a pair of digital signal processors (DSPs). It also contains an Ethernet port and hub, two serial ports, a USB port, and CODEC circuitry for the modem interface. All this, within a single piece of silicon that consumes less than one Watt of power when fully active, and less than 100 milliwatts when idling. The chip is manufactured and distributed through a partnership with Atmel, a leading maker of “application specific integrated circuits” (ASICs).

Since the idea of embedding Linux in small devices has only been around for a little over a year, the Aplio/Phone which was introduced in March, 1998 used the pSOS “embedded” operating system as its initial software platform. But when it came time to design the next generation device, the Aplio/PRO, Aplio opted to switch to Embedded Linux — for two main reasons: first, Linux is free from royalty costs; second, Linux source code is fully and freely available, resulting in great flexibility and configurability.

Aplio selected a version of Embedded Linux called uClinux as the basis of their Internet phones' operating system. uClinux was unique, in that it did not require the sophistication of an Intel (Pentium) compatible microprocessor. “We believe that, with the Aplio/PRO, we had the first small Internet appliance product on the market that used Embedded Linux with a very small footprint,” says Jerome Calvo, president of Aplio's US operations.

Aplio's future plans

Aplio will soon reduce the costs of manufacturing its Internet phones by converting all of the products over to the Aplio/TRIO system-on-chip. Also, the company plans to create new models with added features, like email retrieval and Internet access, in addition to simple IP Telephony. Those functions will be part of a larger device with a built-in LCD display. All of Aplio's new phones will, like the Aplio/PRO, be based on Aplio's evolving embedded Linux software platform — possibly making Aplio one of the highest volume suppliers of products containing Embedded Linux.

Recognizing the enormous market potential for Internet Appliances beyond just phones, Aplio has begun licensing its hardware and software technologies to other companies who wish to bring Internet Appliance products to market quickly and without reinventing the wheel. These technologies include the Aplio/TRIO system-on-chip device, Aplio Embedded Linux operating system port, Aplio's DSP control software, and various other Aplio software layers. Aplio will also license the complete design of their Internet phones to manufacturers who wish to build them under private label. Typical applications for Aplio's hardware and software technologies include Internet phones, email phones, screen phones, and Internet radios.

Incidentally, Aplio's Internet phones retail for $199 and $299 for the Aplio/Phone and Aplio/PRO, respectively, and are widely available through online resellers.

Update: Subsequent to the publication of this article, Aplio was acquired by net2phone. The “Aplio/RAVE” appears to be available via the web from net2phone, here, for $159.99.

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Related stories:

• Aplio/TRIO single-chip Internet appliance
  
• Atmel Launches 1-chip Linux-based “Internet Enabler”
  
• One-chip Linux systems hasten arrival of Post-PC Era

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