How do these symmetries work? Symmetrical bandwidth means that the upload and download speeds are exactly the same. You’ll see this identified as 3 x 3 Mbps Ethernet or 100 x 100 Mbps Fast Ethernet. The classic example of symmetrical bandwidth is the venerable T1 line. It offers a fixed 1.5 Mbps in the upload or transmit direction and 1.5 Mbps in the download or receive direction.
T1, DS3 and SONET are all symmetrical bandwidth services. The reason for this is historical. These are standards developed by the telephone companies to transport phone calls in bulk. The same bandwidth is needed for talk as well as listen on both ends. Ethernet over Fiber and Copper also tends to be symmetrical. It’s because these services were designed as replacements for T1, DS3 and SONET when used in business.
Asymmetrical bandwidth is characterized by differences in the upload and download speeds. This can be as much as an order of magnitude or 10x. You might order a service with 20 Mbps download and 2 Mbps upload or 100 Mbps download and 10 Mbps upload.
Asymmetrical bandwidth is dominant in consumer broadband services. These include DSL, Cable, 3G and 4G wireless, two-way satellite, WiFi hotspots and WiMAX. Why? It’s the nature of the Internet.
Most people browse the Web or download software and video while they are online. When you are doing these things, you are sending commands via your keyboard to the remotely located Web server. These commands are inherently low bandwidth and are based on text you type or links you click on. Neither of these has very many bytes of data involved. Downloads are another matter. Web pages, video clips and streams, music and other audio, software updates and large files are all bandwidth intensive because of their large file sizes. You want the maximum bandwidth available for downloads to minimize load times. You don’t need much bandwidth at all in the upload direction for the usual Web browsing.
What changes this picture? Any process that results in sending out large files as well as receiving them. Examples are remote backups, video conferencing, posting photos and movies online, and making large updates to Web servers. Most consumers do some of these things some of the time. Businesses are far more likely to be sending as much as they receive. But... not all.
If you are heavily involved in big data, cloud computing, enterprise VoIP, video production and distribution, medical image transmission or similar large file operations, you’ll want to opt for symmetrical bandwidth. Fast download speeds may not be so valuable when you wait forever to upload something or try to conduct an HD video conference.
Why pick asymmetrical bandwidth options? The primary reason is to save money. The asymmetrical services like Cable, DSL and 3G wireless are usually priced at a fraction of the cost for symmetrical services. This is generally due to more than symmetry. Asymmetrical services are most often shared rather than dedicated bandwidth. This reduces costs dramatically but means that your bandwidth will vary depending on what other users are doing. There are generally no service level agreements or performance guarantees on asymmetrical bandwidth services. That may be changing as business service providers begin offering dedicated asymmetrical bandwidth options.
What is the best bandwidth option for your business? Find out by comparing prices and features for a wide variety of asymmetrical and symmetrical bandwidth options on carriers serving your business location. Free consulting is also available to help you make the appropriate choice.