Internet bandwidth is always a finite resource, and that’s especially true of upstream connections, where speeds typically range anywhere from 1/3 to 1/12 that of downloads. And when limited Internet connection bandwidth isn’t used efficiently, you can experience performance problems for certain kinds of applications – like VoIP – that rely on speedy data delivery.
Enter Propel Personal Bandwidth Manager, a $29.95 Windows utility (XP-compatible only at the moment, though a Vista version is in beta testing and due out soon) that makes two promises. The first is to keep you informed about how your Internet connection’s bandwidth is being used—i.e., which applications are using it, and how much.
The second is to automatically manage the data flowing into and out of that Internet connection so that time-sensitive applications like streaming media and VoIP applications receive priority over less critical tasks like file transfers, in order to avoid slow video playback and garbled voice communication.
Although it has a few problems, Propel PBM seems to make good on both promises. We say “seems” because the payoff on the second promise may be tough to gauge in many situations.
Before putting PBM on our XP-based Dell notebook PC — connected to an 802.11g network via its built-in wireless network adapter– we went to Speedtest.net to get a reading on the system’s connection speed. The site consistently reported a downstream speed of about 4,250 Kbps (4.2 Mbps) and an upload speed around 360 Kbps via our Comcast cable modem.
Which application hogs the most bandwidth? PBM’s Traffic Monitor displays the incriminating data in both megabytes and percentages.
(Click for larger image).
Installing PBM is a simple matter since you don’t have to configure anything — at least not usually. After ascertaining the speed of your PC’s Internet connection, the software decides on its own how to manage the available bandwidth. According to PBM, our Dell’s connection speed was only 2,620 Kbps downstream (and the same 360 Kbps up).
Another check at Speedtest correlated with PBM’s findings, but when we disabled PBM, Speedtest’s performance figures returned to the pre-installation levels. Propel says that PBM can misidentify connection speed in certain instances, and it provides the ability to override the automatically detected settings when this happens. We did that so the PBM figures would be in agreement with the Speedtest download figures.
Eye in the Sky
We like PBM’s Traffic Monitor feature, which is so named because it provides a big-picture look at how you’re using your Internet connection. Easily accessed through a desktop system tray icon, the Traffic Monitor reports how much data each application is currently sending and receiving, and it also records cumulative data–expressed in both absolute (megabytes) or relative (percent) terms—so you can see which of your applications are the biggest bandwidth hogs over time.
Because the application names displayed by the Traffic Monitor are the same cryptic labels you usually see in the Windows Task Manager’s Processes tab, an Application Info button provides more detail on a highlighted application. The database of info must be pretty sparse, however, because more often than not we found the button offered no additional information. Each info window does provide a link to a Google search of the application name to fall back on.
Traffic Manager has other minor usability issues, too. For starters, the display window lacks the “Always on Top” option (like you get with Windows Task Manager), so if there’s limited screen real estate — as was the case with our notebook—application windows are constantly overlapping Traffic Monitor while you’re trying to read it. Also, Traffic Monitor wipes away cumulative data with every system reboot, which obviously limits how far back the data will go, and likely it’s historical usefulness as well.
Perhaps in a tacit admission that the real-world benefits of traffic management aren’t always plain to see, PBM includes a wizard that aims to demonstrate the utility’s effectiveness through a series of three test calls (the kind where your voice is recorded and played back to you in order to test microphone settings) using Skype or your preferred VoIP utility.
The wizard essentially floods your upstream connection with data to illustrate the difference in call quality when PBM is off and on. In our baseline test call (without any interfering data or PBM involvement) our voice was played back without any problems.
In the second call, with interfering data being sent but with PBM inactive, the playback was unintelligible, indicating that our outgoing Skype voice data had in fact been squelched by the competing traffic. Finally in the last call, with the data still flowing but PBM turned on, our playback quality was markedly improved and almost as clear as it had been in the first call.
Built-in demos are all well and good, but to see how well PBM prevented nonessential network traffic from impeding the important stuff in the real world, we used Skype to make calls that included not just voice but video as well. While the Skype call was in progress, we uploaded a multi-megabyte file via YouSendIt, a Web site that provides an alternative to sending large files as e-mail attachments.
Although we expected this scenario to degrade our Skype call to some degree, we were surprised that the call quality as reported by the other party remained unchanged– which is to say, good– whether or not PBM was enabled (you can toggle it on and off via the tray icon). Even when we increased the number of files being uploaded simultaneously to two, then three — and verified the increased amount of outbound data via Traffic Manager– Skype worked fine with or without PBM.
We then tried the Skype calls again, but this time while sending a large file to someone via e-mail and simultaneously uploading another file to an FTP site. Again, the presence or absence of PBM didn’t cause any detectable difference in Skype call quality. (Because Traffic Monitor is unavailable when PBM is disabled, we couldn’t use it to compare the upstream data rates when PBM was on to when it was off.)
The fact that we were hard pressed to see a PBM effect in action outside the demo suggests that the demo was an extreme scenario that you probably won’t encounter unless you have an especially slow or taxed connection.
We don’t doubt that PBM is actually performing traffic management, but evidently it wasn’t necessary given the 4,250/360k connection we enjoyed in spite of our attempts to overload it. With something like lower-end DSL service (typically 768k up/128k down) or a cellular modem connection, which is slower still, it would have likely been more useful.
It’s also worth noting that because most people use shared Internet connections and PBM runs on individual PCs, the software can’t manage your system’s use of bandwidth relative to others. In other words, PBM can make the best of what you have, but how much you have depends on how many others are on the network and how much bandwidth they’re using. Propel says a future version of PBM will introduce the ability for multiple computers to work together to optimize bandwidth.
For some people, Propel Personal Bandwidth Manager may be worth the $29.99 price tag (as of this writing it’s being offered at a discounted introductory price of $19.99) just for the detailed connection usage data it provides. Most will want to start with the fully-functional 30-day trial version of PBM from Propelpbm.com, so you don’t have to part with any cash until you determine its usefulness given your own connection speed and usage patterns.
Pros: Built-in Traffic Monitor shows you exactly what applications are putting a load on your Internet connection.
Cons: May miscalculate available Internet bandwidth; benefits of bandwidth management not always evident on a 360K upstream cable modem connection; currently not Vista-compatible.
Joe Moran is a former editor and analyst with Ziff-Davis Publishing. He’s currently principal of Neighborhood Techs, a technology service firm in Naples, Fla. He holds several industry certifications, including Microsoft Certified Systems Engineer (MCSE) and Cisco Certified Network Associate (CCNA).