I've done what you are talking about, including someting slightly different (and possibly what you mean to do) called "modem bonding".. Or multi-link.. It's far better than what you've mentioned.. I will explain.

Multi-link: Two phonelines, two modems, two ISP accounts on the same ISP that supports MLP connections.

Multi PPP: Two phonelines, two modems, two ISP accounts on seperate ISPs or a single ISP that does not support multi-link connections.


What you are talking about is not MLP (mulitlink), but some sort of dual PPP dial-up connection. This is impossible for Windows XP to do natively, as well as all other Windows versions. You will need a 3rd party program. Windows XP and 2000 can multi-link though.. There are clear advantages in mulitlink over multi PPP, but I'll get to that later.

Unfortunately, multi-PPP works very badly. Unlike multi-link, the connections are never negotiated to work as a single connection, so you cannot download things twice as fast. Instead, you can download two things, each at normal speed. And then it varies on the efficiency of the program you are using to negotiate your multi PPP connection.

For example, if you usually get 5kb/sec download speeds using a single modem, then multi-PPP would allow you to download two files at 5kb/sec total. However, if you are downloading one file, you will only see 5kb/sec. This is theoretical speed too... Your actual speed will vary greatly depending on the program you are using to multi-PPP.

For browsing the web, multi-PPP is not any faster. For downloading files, it seemed to be eactly the same speed as usual (Under 5kb/sec). Downloading two files however, I could get a max transfer rate of about 30% higher than I usually got... So instead of 4.7k/sec, I got about 6.5kb/sec. Keep in mind this is TOTAL for two files at the same time. It makes no difference for downloading only one file or the download speed of the files individually. If I was downloading only one file, I only got 4.7kb, which is my usual max.

Comparing this to multi-link, multi-PPP is a waste of money (for the extra account, modem and phoneline). With multi-link, I was getting just under 10kb/sec for file downloads and pages loaded really fast... It almost felt like broadband.

However, to use multi-link, your ISP must support it. If there is an alternative, then modem bonding is rediculously expensive. An extra phoneline and ISP account more than double what you may be paying already, for not a whole lot more speed. DSL and cable (if available) are far better options. You may even want to consider satellite if you are willing to spend that much money.

If you decide to use two modems, use multi-link instead of multi-PPP. It's much better. In summary...

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Multi-link advantages:
- Doubles your bandwith for everything.
- Native support on Windows 2000 and Windows XP

Multi-link disadvantages:
- Requires special ISP support
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Multi PPP advantages:
- Well, it works on some level I guess.
- Requires no special ISP support and may be used on 2 different ISPs. Multi-link can only be done using two accounts on a single ISP.

Multi PPP disadvantages:
- Just as slow as normal, except when downloading two files at once
- Under no circumstances is it ever as fast as multi-link.
- Not supported by any Windows operating systems. You will need a 3rd party program which may cost you some cash.
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