Learn how to speed up your Internet dial-up connection with a second phone line and a second modem.

When it comes to surfing the Web, speed is everything. With more and more Web sites moving beyond the static HTML pages of the early years of the Web and offering streaming multimedia, it's becoming essential that you have a high bandwidth connection. As such, many folks are moving away from their 56K modems and enlisting the aid of more powerful connection technologies, such as DSL (Digital Subscriber Lines) or cable modems which offer a dramatic increase in connection speeds when compared to a 56K modem.

Unfortunately, neither DSL nor cable modems are available in all areas of the country. So what can you do to increase your bandwidth if you live in an area not yet serviced by these new technologies? Well, you can investigate MultiLink, a technology borrowed from ISDN and ported over to Windows 9x. It allows you to use two 56K modems as one and effectively double your connection speed. Of course, using MultiLink a bit more involved than just connecting two modems to your system, but it's not too difficult.

In this article, I'll tell you what equipment you need and show you how to configure your Windows system to use MultiLink. As I do, I'll explain in more detail what MultiLink is and how it works.

Wizard Note: DSL and cable modems allow users to send and receive data in terms of megabits, or millions of bits, per second (Mbps). However, keep in mind that DSL and cable modem connection systems vary widely and have different speeds for downstream and upstream connections. As such, it's difficult to give exact connection speeds. Suffice it to say that they offer a dramatic increase in connection speeds when compared to a 56K modem, which transmits information at kilobits, per second (Kbps).

Contents

What you need to use MultiLink

Understanding MultiLink

Configuring MultiLink

Making a MultiLink connection

What you need to use MultiLink

The first thing that you need in order to be able to take advantage of MultiLink is an ISP that supports the MultiLink PPP technology. Without this support, you're dead in the water.

Give your ISP a call and ask them if they provide MultiLink PPP accounts. If your current ISP doesn't support MultiLink PPP accounts, there are a couple of resources you can use for tracking down such an ISP. The first resource is called The List and the second resource is from Boardwatch magazine's Directory of Internet Service Providers.

The second thing you need to use MultiLink is the software. If you're running Windows 98, you're all set as far as software goes because MultiLink comes with the operating system. However, if you're running Windows 95, you need to download and install the Dial Up Networking 1.3 Performance & Security Update, which includes the MultiLink software.

The next thing you need to have is two modems. While you can use two different speed modems, using two of the same speed will yield more satisfactory results. You can use any combination of internal and external modems.

Finally, you need to have two separate phone lines. You'll need one phone line for each modem.

Wizard Note: A few years back there was a rash of new products introduced to the market that included two modems in one package called dual-line or bonded modems. For example, Boca Research had the Dynamic Duo and Diamond Multimedia had Shotgun. Unfortunately, the bonded modem technology never really caught on and these products have pretty much disappeared from the face of the Internet.

Understanding MultiLink

If you have all the required equipment, you're set to go. However, before we get started, let's take a few moments to learn more about MultiLink.

As I mentioned, MultiLink allows you to use two separate modems as if they were a single modem. The MultiLink software configures your modems to collaborate in such a way that your connection speed is doubled. For example, if you have two 56K modems you'll essentially get a connection speed of 112K.

In order to attain this type of speed, MultiLink intercepts data packets heading for the Internet, splits them in two, and sends each half of the packet to a separate modem. Each modem then sends a half packet to the ISP. When the half packets reach the ISP, the server software reassembles the original data packet and sends it out to the Internet. On the return trip, a data packet heading from the Internet to your computer is intercepted by your ISP's server, which then splits it in two, and then sends each half-packet back to one of your modems.

The end result of all this behind-the-scenes magic is that your connection can handle Internet data in half the time. This then equates to doubling your modem speed.

Wizard Note: As you may know, current FCC regulations limit a 56K modem's connection speed to 53Kbps. Furthermore, a speed of 53Kbps is only possible if there is just one analog switch between your modem and the phone company. If your connection goes through more than one analog switch, which is very likely, your modem's data transfer rate drops. As such, most people using a 56K modem typically get a connection somewhere between 45Kbps and 50Kbps. This means that combining two 56K modems with MultiLink will yield a connection speed of somewhere between 90Kbps and 100Kbps.

Configuring MultiLink

Once you have all the mechanics set up, configuring MultiLink is easy. To begin, access the Dial-Up Networking folder. If you signed up with a new ISP, you'll need to double-click on the Make a New Connection icon and create a new connection just like you normally would.

Once you create the new connection, or if your using an existing connection, simply right-click on your connection icon and select Properties from the shortcut menu. When you see the connection property dialog box, select the MultiLink tab. Then, select the Use Additional Devices option to enable the MultiLink configuration page.

To configure your two modems to work together simply click the Add button. When the Edit Extra Device dialog box appears, click the Device Name dropdown arrow and select the second modem. At this point, you'll see your second modem appear on MultiLink tab, as shown in Figure A, and can click OK.

Figure A: When you select an additional modem, you'll see it on the MultiLink tab.

Wizard Note: If your ISP doesn't provide MultiLink accounts, but you have two modems, two phone lines, and accounts with two different ISPs, you can take advantage of a software program that works like MultiLink. MidCore, the company the made the software for the Boca Research Dynamic Duo, still exists and makes an Internet connection-sharing package that, among other things, includes a feature called Modem Teaming.

Making a MultiLink connection

To make a MultiLink connection, just double-click on your connection icon in the Dial-Up Networking window. When you do, you'll see the initial Connecting To dialog box as you normally would. After the initial connection is established, you'll hear the second modem begin dialing the second connection.

As soon as Dial-Up Networking establishes the second connection, double-click the connection icon in the system tray. When you see the Connected To dialog box, select the Details button to expand the dialog box, so that you can see all the details, as shown in Figure B.

Figure B: When you click the Details button, you'll see additional information about your connection.

As you can see, MultiLink allowed me to connect to my ISP with two 56K modems at 100,000bps. You'll always get a connection that can be evenly divisible by two. The reason being that the highest connection that the second modem can establish must match the speed of the first connection.

Also, take note of the Suspend button at the bottom of the dialog box. When you click this button, the second modem hangs up and the connection speed drops down to one modem. This comes in handy if you need to free up one of the phone lines to make a call, and still want to be connected to the Internet.

When you disconnect the second modem, Dial-Up Networking renames the button Resume. When you click the Resume button, the second modem re-establishes its connection and again doubles your connection speed.

Wizard Tip: When using two modems to establish a connection with MultiLink, both modems negotiate the highest connection speed that can reliably support under the current conditions. There are many factors that can prevent them from negotiating their maximum connection speed. These situations are fairly common and aren't something you need to worry about. If you don't feel that the current connection speed is satisfactory, just disconnect and try the call again.

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