|Sling Media Slingbox|
|Summary||Streams any video content over a LAN or Internet to a Windows XP PC.|
|Pros||• Allows remote viewing and control of any video source
• Supports control of many different video input devices and sources
|Cons||• Currently only supports Windows XP and 2000
• Can be tricky to setup in some environments
When Personal Video Recorders became popular a few years back, consumers learned that they could watch TV on their own schedule. "Time Shifting" - first popularized by TiVo - had always been possible with VCRs, but PVRs made it dead-simple to automatically record a large number programs for later viewing.
Now there's another company trying to once again change our TV viewing habits. What if you could subscribe to satellite or cable TV at home, and then watch it anywhere you had an high-speed Internet connection, be it at school, work, or even vacationing half way around the world? And even better, what if, you could do this with no monthly fees to pay? That's the promise of a company called Sling Media, which has coined "Place Shifting" to describe what its new Slingbox does.
When I first looked at the device, I noticed its shape and color was reminiscent of a silver bullion bar. The Slingbox is around 10 inches long, 4 inches wide and 2 inches tall, with a fairly plain front adorned only with power, and network connectivity LEDs and a pattern of red LEDs indicating client connectivity.
In contrast to the front, the back (Figure 1) is chock-full of connectors for both input and output ports that should handle most standard-definition television needs. There are connectors for S-Video, composite video and coaxial video, as well as composite audio.
Figure 1: Back panel showing connectors
In addition to the A/V connectors, there are 10/100 Ethernet , power and infrared extender cable connectors. The infrared extender is used to send IR commands to your chosen video input component, with one end of the extender plugging into the Slingbox and the other end placed near the IR window of the video input component you need to control.
With the number of different connectors available, you can imagine that setup might be a bit intimidating for some users. To address this complexity, Sling Media provides a long user's guide formatted as a large-format, cartoon-like, setup manual that was fairly easy to follow.
I connected the Slingbox up to my satellite receiver, which had an extra composite output available. So audio / video setup for me was just a matter of feeding that output into the Slingbox. If you don't have an extra output available, you'll need to feed your single connection into the Slingbox, and then use another cable to feed it back out again to your TV or AV system.
Network connection was also fairly easy. I have a router in my entertainment center, so it was just a matter of plugging in an Ethernet cable. If you're not Ethernet-equipped near your video source, you'll have a more difficult time, since the only network option for the Slingbox is Ethernet. With signal connections completed, I powered the Slingbox up and in short-order the network connectivity LED showed a good connection. The box had evidently acquired an IP address via the DHCP server on my Linksys WRT54G router.
Other home-network audio / video devices I've used generally display their user interface on a TV screen. But the Slingbox is different because it's not designed to be locally controlled. The Slingbox doesn't even have a power button, much less a remote control. In my setup, it also didn't have an output connection to my TV. All configuration is designed to be accomplished via a PC running an application that connects to the device across the network.
Client support is currently provided for Windows XP only, but Sling Media has recently released support for Windows 2000. They've also made statements that Macintosh OS X, Linux and other operating systems will be supported in the future. So since my iBook wasn't supported, I turned to my XP laptop for installation. The installation program included a "Wizard" that found the device on my home network and started the setup.
One of the first configuration screens displayed had an area for a video preview. Figure 2 (from the manual) shows what the screen should look like, but all I got was a video area full of static. I checked with the "help" option and followed the suggestions of checking cables without change. Finally, I noticed a suggestion to ignore the problem and continue.
Figure 2: Setup
Evidently, the device was trying to acquire video from the coaxial connection, which I wasn't using. When I got to the screen that allowed me to change the input to composite video, my picture came in. It would have been nice to have the input selection on the first screen, or at least have a notice on that screen, indicating where it was trying to acquire video from.
Setting Up, Continued
Continuing with the configuration brought me to a screen allowing me to choose the specific device I was getting video from. In my case, I was using a fairly obscure Dish Network Personal Video Recorder that wasn't listed on the Sling Media list of supported devices. I wasn't sure it would work, but the setup screen allowed me to cycle through several Dish Network options and I quickly found a code that was able to control my unit.
The setup screens also allowed me to password protect my unit for both an administrative and normal users. This is an important step because the device is designed to be present on the open Internet where it is reachable from anywhere in the world. So, unless you want a Romanian hacker to be able to watch and control your TV, pick a good password.
Finally, there was a setup screen for network options. The device defaults to trying to lease a DHCP address, but for long-term use, it needs an address that won't change from day-to-day. If you're going to allow the device to be used from the Internet, it also needs a "hole punched" (forwarded port) in your router's firewall. The easiest way to set all this up is automatically, using the UPnP protocol (Figure 3).
If the router on your network has support for UpnP, the Slingbox configuration will use it to both acquire a static IP address and set up its port-forwarding needs. Since my WRT54G has UPnP support, this was all seamlessly accomplished in a few seconds. If you don't have UPnP support, or if you want to do the same thing manually, there are configuration screens and tips on configuration for your router. Depending on how complex your home network is however, setting up the Slingbox to be accessed from outside your firewall can get complicated, so fairly extensive documentation was provided.
Figure 3: Router Configuration
When you enable your Slingbox to be used from the Internet, a unique ID is automatically generated and registered with Sling Media. This ID can be used in order to find your box when you bring up a client from a remote location, such as work or an hotel. If you're so inclined, you can skip the ID and directly attach using the port number and IP address of your router. This is why it's so important to pick a good password, because if you can connect to your Slingbox remotely, so can that Romanian hacker. Of course, the most he or she could do is watch and control your TV, or maybe order a few Pay-Per-View movies.
Now that I had the Slingbox configured, it was time to check it out on my local network. Using the client software was fairly simple and just a matter of starting the program and using the simulated remote to control my satellite receiver. In general, the video quality was OK, with some visible compression artifacts. Not bad, but certainly not great.
I generally didn't have any problems with "jitter" or stalling that would indicate the Slingbox couldn't get the bandwidth it needed. Controlling my satellite receiver worked fairly well, with all functions available, but it had an obvious lag of a couple of seconds, which is to be expected considering the path the command was taking.
There is an option for "Control Mode," where the commands sent to your device take precedence over video, at the expense of video quality. You might want to use this mode if you are doing a lot of menu interaction, but I found myself just putting up with the lag. The video window could be used in various sizes, including full-screen, but the compression artifacts became more and more noticeable the larger the window became. To further check it out, I took my laptop out to my back yard and successfully watched a baseball game. Who would have thought of it? Wireless TV!
Figure 4: Slingbox in use
(click image to enlarge)
Of course, using the Slingbox on my local LAN was all well and good, but the real appeal of this device is being able to watch and control your home video system while you are away from home. To this end, I tried the client software from a distant location, behind a firewall and through a web proxy.
In my case, it was no sweat connecting and using my Slingbox. I typed in the ID that was generated when I set the box up, entered my proxy information, and a few seconds later I was connected (Figure 5). Even though setup for remote viewing was easy for me, I'm sure that some others might have more difficulty with multiple levels of routers, stricter firewalls, proxies that restrict content, etc. It's not an easy environment to work with.
Figure 5: Entering the ID for remote viewing
When I started my test, I realized I'd forgotten to turn my satellite receiver on as I left home, so I thought I'd have to postpone the test. But then I realized that I had complete control, including turning my system on and off. Once I remotely turned my satellite receiver on, I was able to bring up its menus, navigate and make my selections.
I subjectively judged the video quality to be a bit lower than on the local LAN, but still acceptable. I also found that commands seemed to lag a bit more, which was also expected. Overall, the experience was fun as I controlled my home system from far away. Of course, if someone else were at home using the system, I'd be changing their channel and popping up menus while they were watching. But they also could do the same to me. Note also that only a single Slingbox client can be connected at any one time.
Under the Covers
Figure 6 shows the main board of the Slingbox. The main video processor is a Texas Instruments TMS320-series Digital Media Processor and Ethernet is provided by an ICS 1893BF. To check its presence on the LAN, I did a network port-scan of the device and found only a single port - 5001 - open, which is the standard port used by clients for acquiring video.
Figure 6: Slingbox main board
(click image to enlarge)
While I was at it, I tried pointing VLC, a video streaming "Jack of all Trades", at the Slingbox, but it got nowhere fast. That confirms that the protocol used by the Slingbox is custom.
I found the Slingbox fun to use, and easy to set up. It worked as advertised and gave me a "place shifting" capability that I hadn't had before. But the big question is, do I need that capability? For me, the answer is probably no. I don't need to watch TV when at work. And when I'm traveling and do want to watch TV, I don't need anything more than what a hotel would offer.
But other people will have different needs - at least that's what Sling Media hopes! I browsed some on-line Slingbox forums and saw quite a few people asking questions regarding use of the client software from behind a corporate firewall, so evidently there are jobs out there where it is acceptable to watch TV from your desk.
Whether Sling Media will find a small niche in the market for their product, or whether they'll be able to break into the mainstream, only time will tell. Either way, the Slingbox was well done and a pleasure to use.