Turn Your Old Router into a Range-Boosting Wi-Fi Repeater

If you're upgrading to a faster, stronger wireless router, don't chuck your older Wi-Fi box. With the magic of DD-WRT, you can turn your older wireless router into a range-expanding Wi-Fi repeater to cover everywhere you need a connection.

The advent of wireless home networks grew slowly in the past decade, but reached the point at which nearly every home with a high-speed connection had a wireless router that shared Wi-Fi connections throughout the home. Now Wireless N has become the standard at electronics retailers, promising faster connectivity with your wireless devices, faster transfer and streaming speeds between devices, and better connectivity. So what's to be done with your home's first wireless router?

Our suggestion is to install the open-source DD-WRT firmware on your router and turn it into a repeater for your main router, expanding your Wi-Fi signal to reach every nook and cranny of your house, and even into your backyard or garage, if needed. You'll be able to use the same password and security scheme, you won't need anything except a power outlet for the repeater when you're done, and most of your devices will automatically switch between the two signals when needed.

We've previously run down how to install DD-WRT on a Linksys router to give it many, many more features, including the repeater function we'll cover here. If you've already installed DD-WRT, then, skip to the section on repeater configuration. One notable difference in this guide, too, is that I'm installing a custom build of DD-WRT, the "micro" flavor, on a Linksys WRT54G ver. 6, or "version 6." Adam wrote his original guide in 2006, with a fully-DD-WRT-compatible Linksys WRT54GL router, and at that point, those who picked up a blue Linksys box without knowing about open-source firmware were pretty much stuck. Now there's a huge array of supported devices, and even my sadly restricted Linksys can run a Micro build, and Micro now includes a repeater function.

Update: A Note on Speed

Some intrepid bandwidth watchers, Will Smith among them, have pointed out that their own experiments with repeating signals has left them with slower connections. To be honest, I was using the repeater mostly for Google Reader in bed, and browsing and web working from outside the house, so I hadn't seen a noticeable drop in speed. A few tests at SpeedTest.net tell the tale. Pictured at left here is the result from my main router, a Buffalo model with Wireless N (detailed here), connecting from my upstairs office to the downstairs living room, then Buffalo, NY to Toronto, ON.

This result is through the modified Linksys WRT54G ver. 6 router about 10 feet away, connected as a repeater to the Buffalo router downstairs, and then tested again through Toronto. There is, as you can see, a download speed difference, and if I'd been using my Wireless N modem, it might be even more severe. So take a repeater for what it is—a slight trade-off in speed for a greater reach, with your mileage varying based on your hardware and connection. You might also note, though, that using SpeedTest's Android app, I actually received better download speeds from my office through the repeater than through the main router—for a smaller antenna, perhaps, connectivity can sometimes win over latency concerns.

What You'll Need

• Compatible router: Grab that old-but-still-works router and flip it over. Get the model number off the label, and write down the MAC address, while you're at it—the locations for both, on a standard Linksys "blue box," are pictured above. Type the first few characters of your model number into DD-WRT's router database, and look for your model to pop up. If you get any kind of green "Yes" listed with your model, you're in the clear—even the most pared-down DD-WRT build, micro, supports the repeater function.

• Firmware files for your router: In that same router database, click on the line that relates to your router model, then grab all the files listed there. You may not end up using all of them, but once you've taken your router offline, even if it's not your main router, you'll want to have all your files available offline.

• Print-out of your instructions: There's a good chance, if you've got a fairly popular router, that you'll have access to specific router model instructions on the DD-WRT wiki. You'll usually see a link on the same page as your firmware files; if not, go ahead and search the wiki. If you don't have a printer, or hate wasting paper, use a print-to-PDF tool like doPDF or the Nitro PDF Reader for Windows, or the built-in PDF functions in Mac or Linux. The reason, again, is that you want to be prepared in case you lose internet connectivity on one or more routers during the flash process.

• Ethernet cable & computer with Ethernet port: Enough cable to comfortably reach from your computer to the router you're working on, and a computer without any networking problems that you know of.

• A pen and paper: The paper for notes, and the pen for both writing and pressing and holding down the reset button on your router.

• At least an hour's time, and patience: Instructions for most routers are laid out in step-by-step detail, with very specific instructions. Even so, you do not want to rush things, or load the wrong file at the wrong time. Doing so opens the potential for a "bricked" router, one that doesn't work and can't be accessed or set back to its default, factory-fresh state. That's not going to happen to the patient, cautious firmware flasher, though.

Get Started

As stated above, different routers will take different paths to installing DD-WRT. There are some common procedures, and a general path, to getting it installed, though, so you can read along as I follow the DD-WRT Wiki's instructions for a WRT54G version 6 installation.

• Do a hard (30/30/30) reset on your router: A "hard" reset, or a "30/30/30," means locating the reset notch on the back of your router, then inserting a pen and holding it there for a total of 90 seconds—30 seconds at first with the power on, then yank the power cord and wait another 30, then plug the power cord back in and wait 30 seconds, all while still holding the pen. It seems a bit excessive, but trust me—I've had friends with electronic engineering skills explain just how finicky, and sometimes random, physical memory chips like those in routers can be at holding their settings or otherwise not completely blanking out.

• Set a static IP address on your computer: Most DD-WRT guides want you to set your computer's IP address, the one it draws from your router, to 192.168.1.7, and set a subnet mask to 255.255.255.0. How do you do this in your computer, without the router being accessible?

Head to Windows' Network and Sharing Center, usually by right-clicking on your network connection icon in the system tray, or heading there through the Control Panel. In the left-hand panel, click "Change adapter settings," then right-click on your "Local Area Connection" offering and select Properties. Under the Network tab, select the "Internet Protocol Version 4 (TCP/IPv4)" and hit the Properties button. Now in the General tab, change the first radio switch button to "Use the following IP address:", then enter 192.168.1.7 in the IP Address field, and 255.255.255.0 should fill itself in under "Subnet mask." Make sure you've got the IP entered correctly—Windows can skip the "7" part if there's only a single digit in the third section—and hit OK when you're done.

Firmware Installation

Now we're gonna get serious. Connect the Ethernet cable between your computer and the router—be sure to insert the cable into one of the numbered ports, not the port labeled "Internet" that's slightly distanced from the others. Turn off any wireless connection to your main router, unplug any broadband cellular modems, and so forth.

In the case of my WRT54G ver. 6, I had to create a customized flashing image for my router, with a designated MAC address written in. The MAC address is a supposedly unique identifier given to all computer hardware that can access the internet, one that allows networks to allow and block hardware based on this address. Your internet provider and the the cable modem they provided also tracks the MAC address of your router, and can deny service if a different router than the one the modem is used to servicing suddenly appears. So I followed the instructions for downloading GV5Flash.zip, unpacking its contents, then running the vximgtoolgui application and filling in the MAC address I wrote down from underneath my router, and pointing the app at a place to drop the resulting .bin file.

Now you're going to pull off one of those "hard," or 30/30/30 power cycles—hold down reset for 30 seconds plugged in, 30 unplugged, then 30 seconds again plugged in. When you're done, wait a few seconds, open your browser (making sure your computer's still connected by cable), point it to http://192.168.1.1, and you should get a prompt for a username and password. The default for my router in this mode is "root/admin"—yours can likely be found at RouterPasswords.com, or in your own DD-WRT instructions. After entering that combo, you should see the default router screen. A Linksys default usually looks like this:

In most cases, you're next going to head to the Administration section (circled in the pic), then click the Firmware Upgrade sub-section. It's usually a simple affair: a Browse button to find the file you want to upload, and an OK/Apply button to set it in motion. From here on out, unless you have my same exact router, you'll possibly have a different set of one or two files to upload, in a very particular order—follow your own DD-WRT customized instructions. In general, though, you'll be doing a procedure along these lines:

• Uploading a "prep" file that gets your router ready for a new firmware.
• Waiting a solid five minutes—no cheating.
• "Power cycle" the router (a simple unplug, 30-second wait, then re-plug).
• Re-connect to 192.168.1.1, see the "Management Mode" window, then upload your (possibly customized) specific DD-WRT image and hit Apply.
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• After seeing this nice little "Upgrade Success" message, wait another full, honest five minutes.
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• Open a TFTP program, usually provided among your DD-WRT files, and point it at 192.168.1.1 (your router). Select your specific DD-WRT firmware (a micro build, in my case), then set the retries to 99—But! Before hitting "Upgrade," power cycle your router, wait a few seconds after re-powering, then go for it. When your TFTP app has a green light and success message, wait another full five minutes, then come on back.
• Undo the static IP setup you put in place on your computer from the Network and Sharing settings. Unplug and re-plug your cable, then open a browser. If you can connect to 192.168.1.1 on your computer browser and see a setup page for DD-WRT, do a (final) 30/30/30 "hard" reset on your router, then check that you still see the DD-WRT setup. If so, you're all set up!

Setting Up the Repeater

Now that you've got your oldie-but-goodie router set up with DD-WRT, you can set it up to pick up the signal from your primary router and re-broadcast it within its own radius. Here's how to do that.

With your computer still hooked up to the now-secondary router, head into the DD-WRT setup screen. It will ask you to set a better password and username at first, so go ahead and do that—you'll probably want to set up the same admin/password as your primary router to avoid confusion. Once you're in, your setup screen will look something like this, as my Micro setup on my Linksys appears:

First up, click on the Wireless tab, then choose Basic Settings. Switch "Wireless Mode" to "Repeater," and the "Wireless Network Name" to the same as the main router you're going to be re-broadcasting. Don't worry about the bridged/unbridged radio buttons—they'll set themselves later. Hit the "Save" button at the very bottom, but do not hit "Apply Settings" just yet.

In the "Virtual Interfaces" section, below that main "Wireless Physical Interfaces" section you just modified, hit the "Add" button, then enter a new name for your repeater—don't use the same as your router, or else suffer the wrath of confused devices. Adding "Repeater" or "2" to the end of your main router's name is pretty sensible in most cases. If you prefer an access point that doesn't broadcast its name, save that for switching off later—while we're testing our repeater, we'll be using basic settings to make sure the connection goes through. Hit the "Save" button at the bottom again.

With the main Wireless tab still selected, head to the "Wireless Security" sub-tab to the right. You'll see two interfaces again—a "Physical Interface" and a "Virtual Interface." In the "Physical Interface" section at the top, fill in the same exact security settings as your primary router—the security mode, the algorithm (TKIP or AES, generally), and the password any device would use to connect. You might need to jump back into your primary router settings to confirm these—that's fine, but do so from another device. Under the "Virtual Interface" section, set up the same exact security settings as your primary router, again. Hit the "Save" key at very bottom again and, again, avoid "Apply Settings" for the moment.

Jump over to the Setup tab at the very top, then scroll down to the Network Setup section under Basic Setup. The main thing to do here is slightly alter the "Local IP Address" from what your primary router is. If you connect to your main router at 192.168.1.1, for example, set this repeater router to something like 192.168.2.1, or another number that you can remember in the second-to-last position. Hit (you guessed it!) Save.

Finally, head to the Security tab up top, and in the Firewall section, disable the "SPI Firewall," and un-check everything under the "Block WAN Requests," except "Filter Multicast." Hit "Save" at the bottom one last time. Finally, head over to Administration, double-check that you've got your administrator password written down or remembered, and hit "Apply Settings" at the very bottom. Your router will reset itself now, so give it time to do so.

Unplug your computer's Ethernet cable, turn on a wireless device, and see if you can find your new repeater bridge. Connect to it, use the same password you'd use for the main router, and you should have success. If not, run through the steps and double-check your settings. DD-WRT's wiki page for WLAN Repeaters has a good deal of troubleshooting advice, so check there too.

You've now got a second Wi-Fi station in your house that picks up signal from the main router and offers it out to devices that are farther out. It's likely not as fast a connection between devices—it's wireless G, in most cases, as opposed to N. Then again, at this point, there are very, very few services or streaming applications that make full use of Wireless N's crazy bandwidth potential, so your Hulu streaming, web browsing, and other usual internet life will likely be unaffected.

In my own case, my wife and I don't have to use modern-day divining tricks in our very non-linear Victorian home to keep a spotty Wi-Fi signal to an iPod touch or Android phone, and a side patio has just become a preferred secondary home office for the summer. As a bonus, my closest neighbors now know that I'm a serious, serious nerd when they fire up their laptops. Here's hoping you find similarly fun and free uses for a Wi-Fi repeater.

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How is your repeater working out for you? Do you have any suggestions on making the repeater more convenient, or another guide for DD-WRT, Tomato, or another firmware? We'd love to hear your comments, questions, and tips in the comments!

Why Streaming Video Over 3G Sucks

The thing about wirelessly streaming video to millions and millions of phones is that it's, like, hard.

Wireless vs. Wired

Why is it, you might be wondering, that wireless speeds can't just zoom zoom, faster faster, the way that Verizon or Comcast seem to press a button and magically, new, faster internet speeds appear. Well, for one, it's not that magical—even cable and fiber optic "wired" broadband costs billions of dollars per year for new internet pipe, with plenty of griping from carriers about videos and torrents and other bandwidth hoggery, hence all the buzz about net neutrality.

But there are more demanding constraints when it comes to wireless broadband:

• Speed: No matter what happens, wired technologies will be faster than wireless, because electrical impulses guided upon a wire, or optical impulses running through fiber, are more efficient than radio waves scattering themselves into the air in the hope of getting picked up.

• Reliability: Even when you can consistently pick up wireless signal, its strength may vary, not just because of how close you are to the cell tower or Wi-Fi hotspot, but because radio is blocked by the foliage on the trees, or the water in an aquarium.

• Cost: Delivering the same bandwidth wirelessly will always be more expensive, because radio waves—due to the above constraints—require massive amounts of power to work well. As we'll see, there's also a matter of paying for the right to use radio waves, a privilege that is only granted after payouts in the billions of dollars.

If that sounds a bit remedial, it's supposed to: Wireless always, always lags behind wired. Think of how much faster gigabit ethernet is compared to Wireless N. It's just how the world works. But people want wireless connections, in their pockets, for obvious reasons. What we're talking about is why it's so hard to pull off well.

What's Coming

See that chart up above? That's the growth of data traffic on AT&T's network over the past four years. Despite all the email, photos, music, tweets, apps and voice data traveling across the network, the single largest type of traffic is video. Funny thing is, the true video explosion hasn't happened yet.

What do I mean by that? Well, take Netflix's Watch Instantly streaming video service, for example. Right now, the only mobile device it's available on is the iPad, with an iPhone app promised by the end of the year. But Netflix's vision is to be on basically every device with a screen. Imagine a world where every phone, millions and millions of them, can stream nearly any movie over the air. Where phones with bigger, better, higher res screens demand serious quality video to take advantage of the extra pixels. Multiply that by apps current or future apps for Hulu, SlingPlayer, ABC, CBS, NBC, HBO, Vimeo, and oh yeah, YouTube.

Not to mention streaming video from phones, which are on the verge of universally breaching HD quality recording. Today, Microsoft's Kin phones—running on Verizon's 3G network—automatically upload every 5- and 8-megapixel photo, every 720p video you record, to the cloud. They're just the first, to be sure.

Two years from now, that bar at the far right of the chart may appear as tiny as the one at the beginning, compared to the traffic that's coming.

There are three major constraints on streaming video to a mobile device over the air: wireless spectrum, backhaul, and the device itself.

Need More Spectrum, Dude

Wireless spectrum, while invisible, is not an infinite resource. In fact, it's pretty damn constricted, at least in crowded urban areas.

To radically simplify it, an easy way to think about spectrum is kind of like a highway, divided into lanes. In the US, the FCC designates who and what's allowed to travel in each lane. (Check out the FCC's spectrum dashboard to see who owns what spectrum where.) The FCC typically divides the spectrum into "blocks" (stick with the mixed metaphor here) that are 10- or 20-MHz wide (so a carrier would get, say, a slice from 700MHZ to 710MHz). A standard configuration is for a carrier is to use half of each block to send a signal, and half to receive (outbound and inbound traffic). Each lane/block can only carry so much traffic. So when you get a ton of people pumping a ton of stuff over the airwaves in a small area, you run into issues.

The solution, though, is not simply to build more cell towers for a given frequency ad infinitum—it doesn't actually create more wireless spectrum in the universe for signals to travel on, and in fact, if you crowd too many towers too close together, you get bunch of noise and interference. Basically, you don't paint extra lines on a freeway in order to make way for more cars.

The best solution, from a carrier perspective, is to get more spectrum allotted from the FCC. Typically the rights have to be purchased for billions of dollars, as you might've noticed during the frenzied devouring of the 700MHz block by AT&T and Verizon for their upcoming 4G LTE networks. The thing about 4G is that is uses really fat channels—really wide lanes—which is why they can transfer data really fast.

As a side note, not all spectrum is the same: If you remember your high-school physics, lower frequencies travel farther with less energy, and penetrate buildings better too. As such, they are better suited for sharing massive amounts of wireless data, hence the popularity of the 700MHz block, for carriers who generally deal with spectrum from 1700MHz to 2100MHz.

No matter how many FCC auctions, limited spectrum availability for carriers dealing with a data tsunami is going to continue to be an issue—Clearwire says a 120MHz-wide slice of contiguous spectrum is what's needed for legit mobile broadband. The wireless industry association CTIA says the whole industry needs about 800MHz of spectrum total, as opposed to around 400MHz currently allotted. That's why part of the FCC's national broadband plan is to reallocate 300MHz more for mobile broadband in the next five years.

Need More Backhaul, Dude

Next up is backhaul, which is basically the connection between cell towers and the rest of the network. Even if a carrier had a virtually infinite amount of spectrum to carry all of that data back and forth between phones and towers in a fantasy world with exceptional signal strength and no interference, they'd still need fat pipes running from each and every cell tower.

Without decent backhaul, cell towers will run into the same kind of congestion problems you run into at home when you're trying to torrent more than your internet connection can handle. Everything slows down, and it sucks. The problem is that a huge portion of the cell towers in the country are still connected using slow copper lines, and running fiber backhaul to them is expensive. (No carrier will reveal how much of their backhaul is actually fiber for competitive reasons.)

There is also the option of a wireless microwave backhaul, but it requires cell towers that are in the same line of sight, and at some point the data still has to go wired.

The Phones, They Are Puny

The final constraint on delivering streaming video over the air? The phones themselves. Sure, the chips inside of them may technically support wireless broadband speeds of 3.6 or 7.2Mbps, or even faster, but actual speeds tend to be about half of their theoretical maximum, in part because running full blaze would kill their batteries that much faster. And remember those phones with the antennas you had to yank out? Tech may have gotten better, but those antennas went away for mostly cosmetic reasons—we'd be better off with big old metal wands sticking up out of our Droids and iPhones.

Let's Talk About the Video

Okay, so let's talk a bit about the actual video, and the ways it gets it to you. As it turns out, there are actually special standards in place for mobile video that are a bit different from the more familiar standards for the general internet, since they're designed specifically for phones. But, with phones getting better and better at handling the real web—since they're just very personal computers—a shift is happening, so that mobile standards are more like the real internet.

Some of the most standard, um, standards are defined by the 3GPP and 3GPP2—the 3rd Generation Partnership Project (roughly, GSM stuff, so in the USA, T-Mobile and AT&T) and 3rd Generation Partnership Project 2 (roughly, CDMA stuff, concerning Verizon and Sprint)—which lays out standards and specifications for telecommunications things, including mobile phone multimedia. In fact, they even have specified container formats for audio and video (the file candy coatings around the codec center, like h.264 or MPEG-4 or MP3) called 3GP (defined by the 3GPP for GSM phones) and 3G2 (designed by the 3GPP2 for CDMA phones) that most 3G phones can play.

More importantly, though, is the 3GPP's specification for a packet-switched streaming service—explained in great detail here (PDF)—and its protocols like Real Time Streaming Protocol and the Real Time Transfer Protocol (RTSP and RTP), which define one of the major frameworks used to stream video to mobile phones. The main thing to know about is that they're designed to be global standards, and they're built to adapt to wildly varying network conditions, adjusting bitrates on the fly. And if a carrier or service is serving 3GPP video to mobile phones, they need special servers to do it.

But because of wirelessly connected netbooks and devices like the iPad, more and more video comes over mobile networks in the form of good ol' HTTP. The hyper-text transfer protocol—the basis of all web browsers—comes in two general flavors. There's non-adaptive HTTP streaming, which is incredibly simple, just a stream pumped out at a given bitrate, no matter what the network conditions. Trouble is, it's so simple, you're apt to see plenty of stutters and freeze-ups if your network connection suddenly goes south.

HTTP adaptive streaming is what it sounds like, a smarter take on HTTP streaming that it adapts in real time to network conditions, switching to different bitrates depending on what the current bandwidth situation is like. It doesn't require a special server, either. It's actually what Apple uses as its standard for streaming video over-the-air to the iPhone and iPad. (They call it HTTP live streaming.) Microsoft has its own spin, called smooth streaming.

A quick word on codecs. Just like much of the internet has anointed h.264 as the standard for internet video, so goes mobile video. Verizon and SlingPlayer, for instance, both currently use WMV for their streams, but without promising anything, Verizon says "h.264 looks like it's got a lot of promise," while Sling says they're definitely moving to h.264 (as they already have on the iPhone), since it's a "tighter codec" that'll help them use a little bit less bandwidth and support hardware accelerated decoding. Of course, Apple's HTTP live streaming only supports h.264, so if you use an app that streams video over 3G, it's coming via HTTP live streaming, and it's encoded in h.264.

(In case you were curious, most of the 3GPP video is encoded in h.263 MPEG-4, with AMR audio, but it's gradually shifting to h.264, too.)

An Alternative Approach to Streaming

So, there are two broad approaches to get video to you—unicasting and multicasting. Unicasting is what I mostly described above, and what you're probably most familiar with, actually. When you look at a YouTube video, pull up a Netflix stream, watch a video on a site, or any kind of standard internet video, it's probably unicast—it's going to you on demand, from start to finish. Multicast, on the other hand, is basically broadcasting—it's being pumped out there continuously for any number of people to pick up. It works best for live events, like news or sports, but if you don't jump in at the start of an event, you'll miss something.

The most prolific of the multicasters in the US is Qualcomm's MediaFLO, which exists as a separate service, and is offered through Verizon's VCAST and AT&T's Mobile TV. It requires specific phones with MediaFLO-support, since they need the MediaFLO receiver and decoder chipset. The basic flow, if you will, is that Qualcomm takes content from a broadcaster, sends it out to its own national network of broadcast towers, and phones can tune in—just like broadcast TV, but beamed using the FLO protocol.

The advantage of multicasting is that it's extremely scalable: For crazy live events—say, the Super Bowl or World Cup—it's no more demanding to serve video to a million phones than it is to ten thousand phones. And since MediaFLO uses Qualcomm's own setup, it takes strain off of the main cell network for the carriers. That's why Qualcomm sees MediaFLO as complementary to the growing availability of streaming on-demand internet video.

The Current State of Video

What kind of video are we actually getting today, anyway? Does it actually look decent? Well, here's a brief assessment.

Verizon's VCAST service adapts to the device—meaning they have to encode a single video several times at varying quality levels—so at the top end, a phone like the HTC Incredible would get a stream at around 256kbps and 15fps and Verizon is exploring going higher, up to 400kbps with 30fps. AT&T still prefers 3GPP video, since most of its phones support it, streamed at bitrates between 64-200kbps. Qualcomm's MediaFLO broadcasts a single stream of 320x240 stream. And Apple's HTTP live streaming specs for cell networks—which every video streaming app for iPhone and iPad has to use, from Netflix to Sling—run from 64kbps to 240kbps. All of them are a long, long way from HD.

Netflix over 3G is actually impressively watchable today. But with 4G networks—LTE and WiMax—and new devices with faster, more energy efficient processors, a near-future where we're all streaming near-HD video anywhere and everywhere isn't so far away, if you squint hard enough.

You know, unless we really do explode the internet.

Still something you wanna know? Send questions about streaming video, sprinkling, or squirting here, with "Giz Explains" in the subject line.

T-Mobile HSPA+ Speed Test: 3G Gets Pumped Up to 21Mbps

Streaming HD video. Uploading gigantic files. Surfing the web comfortably. These aren't things you'd normally expect on 3G. But T-Mobile's beefed up HSPA+ network, which I tested recently in the first city to launch, handled these tasks beautifully. Simultaneously.

While the other carriers are looking past 3G to 4G technologies—Sprint with its WiMax already up and running, and AT&T and Verizon banking on LTE—T-Mobile is the one doing the most to upgrade the 3G network it already has in place. Overhauling their existing HSPA 3G network to HSPA+ promises theoretical speeds of 21Mbps—three times faster than the 3G we know and don't quite love.

In my testing throughout Philadelphia, the first city to get the upgrade, I found that I was routinely getting triple the speeds we expect from 3G nationally—take a look at our nationwide 3G megatest if you need a refresher—with the HSPA+ network averaging in the high 3Mbps range and peaking at 7.81Mbps in one location.

The 3x jump makes a big difference. Consistently averaging download speeds in the high 3Mbps range might not seem like a terrific improvement, but in practice it puts the experience a lot closer to the broadband you take for granted at home than the crippled access you're often stuck with on 3G. And I really tried to push the HSPA+ network by using the internet the way I would at home, at my most extreme. At one point, I was uploading a several-hundred megabyte file to FTP briskly (around 150KB/sec), downloading a torrent even more briskly (~350KB/sec), and still loading web pages quickly and all at once, instead of piece by frustrating piece. At the end of the day, when I was done with all my testing and just catching up with the stuff I follow on the internet, I didn't immediately ditch the 3G and jump back on Wi-Fi. I didn't feel the need to.

Philadelphia is the first city to get pumped up to HSPA+, though T-Mobile is aiming for coverage in major cities across the nation by the end of the year. Since it's not a new network, just an expansion of their current one, many customers who live in areas with HSPA+ coverage will see improvements in speed with the gear they're using right now. Anything that's HSPA 7.2 compatible—that includes HTC HD2, myTouch, Moto CLIQ, Moto CLIQ XT, Samsung Behold II, HTC Touch Pro 2, Dash 3G—will notice snappier speeds. But to really see things crank, you'll need a dedicated HSPA+ device, and T-Mobile's first is the webConnect Rocket USB stick. I tried out the Rocket, which works with Mac and PC, all over Philly, and was impressed with the results.

I tried the same tests we used in our nationwide 3G test: several runs of speedtest.net, several timed page loads of the Wikimedia Commons Hubble page, and several timed loads of a big Hubble image itself.

Here's where I went. Some of the places were suggested by T-Mobile as optimal testing spots—and cheating or not, I followed them in search of the biggest bandwidth readings. But even when I was off on my own, I found that my speeds rarely dipped to levels currently attainable by standard 3G, and were often, as you can see, much much faster, including latency under 100ms at almost every location.

View Philly HSPA+ Testing in a larger map

The webConnect Rocket USB stick is on sale now and can be purchased for $99 with a 2-year contract or $199 without one. With the contract, you get T-Mobile's EvenMore Data Plan, which will run you $59.99/mo for 5GB data or $29.99/mo for 200MB data, and without it the Rocket gets the EvenMore Data Plus Plan, costing $49.99/mo for 5GB and $19.99 a month for 200MB. If you pay full price up front, the stick pays for itself in 10 months, which might be a good deal, as it's just about how long HSPA+ will enjoy its mobile broadband crown until AT&T and Verizon start deploying LTE in 2011.

That 5GB data cap, however, could be a problem. With the 3G speeds we're used to just surfing the web can be a chore. Downloading big files or watching HD video were usually out of the question. But since the HSPA+ feels like your broadband at home, it's easy to treat it that way, and I can imagine users racking up 5GB dangerously quickly. By my back of the napkin calculations, at the speeds I saw, it'd only take about 4 hours of continuously downloading files to eat up your month's allowance. I forsee customers clamoring for beefed up plans to match T-Mobile's beefed up network.

T-Mobile says they are planning "broad national deployment" for HSPA+ by the end of 2010 and will be naming specific cities at the CTIA conference starting next week. How aggressively they roll out the upgrades will determine the fate of HSPA+, if it emerges as a worthwhile pre-4G alternative or if it falls to the footnotes of mobile broadband history. But if you have the need for speed and HSPA+ makes its way to your city, it's definitely worth your attention. It's so fast, you might forget it's 3G.