SmartStream

For those who stream video from online sources, the speed at which data can be sent into their home is critical. If your connection isn't fast enough, streaming video can sometimes stall as it fills the buffer in the receiving device, or the content provider might send a lower-quality stream because it senses that your available speed can't handle anything more.

What many refer to as "Internet speed" is actually the bandwidth available to accept data from the Internet into your home. Measured in megabits per second (Mbps), it's the amount of data that can be transferred from "the cloud" to your connected devices in one second.

For years, I lived in a rural area. We were excited to get DSL with speeds over 1 Mbps. At that speed, a standard-definition Netflix movie would stall and buffer or freeze altogether. Now, I live in a town that has broadband cable with a ridiculously fast top Internet speed of 100 Mbps.

Currently, no video streaming requires anything close to 100 Mbps. But all of the Internet-connected computers and devices in your home network share the total bandwidth you're paying for. Some of the bandwidth might be used by others in your home who want to stream to their TV or play online games. Also, if your neighbors subscribe to the same cable provider or share your building's overall bandwidth, that can decrease the bandwidth you have available if they all want to stream at the same time.

As you'll see below, even a huge video file with 3D and 1080p resolution and Dolby Digital Plus audio requires less than 10 Mbps. Still, if you want to stream 3D or 1080p videos, I recommend opting for an Internet speed of at least 20 Mbps. This takes into account that others might use the Internet at the same time.

At 20 Mbps or more, video streaming of most content will usually run as smoothly as live TV. Yet, several factors could still cause the video to stall and buffer. Popular streaming services could have too many people trying to access the same video at the same time. Perhaps you're streaming in the evening when demand for bandwidth is high in your neighborhood, or others in your house might also be streaming HD content.

If you have an older router with limited bandwidth capabilities, your streaming device might not be receiving all the bandwidth it needs. This is especially true of WiFi connections, which can also be problematic because of interference from other wireless devices in the home. If router is more than three years old and want to stream video, consider investing in an AV router like Netgear's WNDR 4500, D-Link's Amplifi, or Western Digital's MyNet900.

Netflix, Hulu Plus, and many network-TV streaming sites will automatically test your Internet speed before a video begins streaming. Based on its determination of your speed, it will deliver the best video quality—from standard definition to 1080p—that it thinks will run smoothly on your computer or device.

Vudu gives you the option of manually testing your Internet speed before renting or buying a movie, as shown in the screen shot above. You don't want to pay more for a high-quality video only to have it stop because your Internet connection isn't fast enough. To test your network speed, go to the "My Vudu" tab and click on "Info & Settings." Choose the Network test and run the test to see what speed Vudu recommends for your player. If you do rent a high-quality movie and it repeatedly stops to buffer, a message will appear offering to downgrade the quality of the movie you are watching for smoother video streaming.

Here is a list of the Internet speeds recommended by several popular streaming services:

Netflix

• 1 Mbps for viewing on a laptop computer
• 2 Mbps for SD video on a TV
• 4 Mbps for 720p HD video
• 5 Mbps for "the best video and audio experience" (according to Netflix)

Hulu Plus

Note: If a TV show or movie repeatedly needs to buffer, Hulu Plus will stop streaming the video and recommend that you downgrade the video quality.

• 1 Mbps for SD video
• 2 Mbps for 720p video
• Over 3.2 Mbps for best quality HD video and audio

Vudu

Note: All Vudu movies are streamed with Dolby Digital Plus 5.1 audio.

• 1.0 - 2.3 Mbps for SD video
• 2.3 - 4.5 Mbps for 720p video
• 4.5 - 9.0 Mbps for HDX 1080p video
• Over 9 Mbps for 3D HD movies

One thing is certain: Our need for faster speeds will continue to grow. Perhaps we will be streaming 4K video sometime in the future, or we'll need more bandwidth for high-resolution audio formats. But just as dial-up speeds were less than a hundredth of the speed we need today, we will find uses for gigabit Internet speeds in the not-too-distant future.