DS3 Internet Service Options

Medium size businesses and large corporations that have long exceeded the bandwidth available from T1 lines have migrated to DS3 Internet Service as the next logical step in telecom line services. Now there are more options than ever before for smaller businesses that have large bandwidth requirements and larger operations that need and want this level of service.

DS3, or Digital Signal level 3, is a longstanding telecommunications standard for digital transmission. It offers highly reliable 45 Mbps bandwidth for dedicated point to point, PBX telephone, or Internet connections. Smaller Internet Service Providers find DS3 service to be the right size and price to serve their customers. Other key applications are medical image transmission, video transport, and call center operations.

When DS3 was first deployed by the telephone companies, it may have been delivered by coaxial cable, microwave relay tower, or even rigid waveguide pipes. As soon as fiber optic trunk cables were available, DS3 logically moved to fiber based delivery. This is still the standard transmission medium for DS3, especially over long distances. Multiple DS3 signals are often multiplexed onto an OC3 or higher level SONET fiber optic carrier and demultiplexed to be dropped off where needed.

Recent developments by new network service providers with their own regional and nationwide fiber optic networks have dramatically lowered the price of DS3 services to where they are affordable by businesses and organizations that couldn’t previously afford the lease rates. They’ve also deployed additional deliver platforms so that there are multiple ways to get DS3 Internet.

If your building is already lit for fiber optic service, that’s likely the best option for DS3 Internet. If not, you might consider moving your high bandwidth Internet servers to a colocation center. Colo centers generally have the best prices on WAN bandwidth and the availability of multiple carriers to choose from. Construction costs are minimal due to everything being in the same building.

For business locations in a metropolitan areas, including nearby suburbs, there are a couple of other options for DS3 Internet. One is wireless transmission. This is line-of-sight microwave transmission on licensed bands from a carrier’s point of presence to an antenna on your building. It only works fairly close to the carrier and if there are no obstructions in the way.

DS3 over Copper isn’t affected by terrain or building density. This service uses multiple pair of standard twisted pair cabling to transport a DS3 level signal. Special modulation equipment is needed at each end of the path, which is provided by the carrier. DS3 over Copper (DS3oC) is also a relatively short range transmission scheme and is generally available only near carrier facilities.

Would your business benefit from a dedicated DS3 Internet connection, or do you already have one? If so, you owe it to yourself to check prices and availability of DS3 Internet for your business location. You may be surprised to find lower prices and more options that you expect.

The DS1 DS3 Relationship

If you are involved with business telecommunications networking or need to be, you have probably heard the terms DS1 and DS3 bandied about. But what do these terms really mean and where did they come from?

The DS in DS1 and DS3 stands for Digital Signal level. It is a designation that is used to specify the capacity of a digital line in the T-carrier system. You know the most popular T-carrier service as T1. Another popular service is T3. In simple terms, DS1 goes along with T1 and DS3 goes along with T3.

Now, let’s see what’s behind these DS levels and T-carriers. The history of this system goes back to the 1950’s, when Bell Labs recognized the advantage of changing from an all-analog telephone system to digital connections between telephone company offices. Digital transmission carries many conversations on few wires and eliminates the noise and cross-talk that were commonly heard on long distance calls at that time.

The most basic service is one two-way telephone conversation. That was made the most basic element of the T-carrier system and given the designation DS0 or Digital Signal level zero. A DS0 signal is the digital representation of a single voice call. It has a bandwidth of 64 Kbps formed by sampling the audio conversation at a rate of 8 Kbps with 8 bits of data. Those numbers are critical, because they represent the minimum bandwidth needed to give the same audio quality as an equivalent analog phone line.

If a DS0 is one phone call and consumes 64 Kbps of bandwidth, then what is a DS1? DS1 is a collection of 24 DS0 “channels” packed together in a bundle. That’s 24 separate telephone conversations. The bandwidth for this bundle is 1.536 Mbps. When you add 8 Kbps for synchronization, the total bandwidth is 1.544 Mbps. It’s commonly referred to as 1.5 Mbps. A T1 line is a DS1 digital signal package carried on a very specific physical network consisting of 2 pair of twisted pair telco wires with a defined voltage and waveform characteristic.

That’s what DS1 means. Now, how about DS3? If you bundle 28 DS1 signals, the equivalent of 672 DS0 voice channels, you get a DS3. The bandwidth of this signal is 44.736 Mbps, often referred to as 45 Mbps. A T3 line carries a DS3 signal on coaxial cable, although T3 service may also be sent by microwave.

Now, here’s where things get interesting. You can generate the DS digital signal protocol but not necessarily use a T1 line or T3 line for transport. In a process called multiplexing, multiple DS1 and DS3 signals can be combined and transported over fiber optic cable. The SONET fiber optic services were designed to directly accommodate this. The lowest bandwidth SONET service generally available is OC3, which carries 3 multiplexed DS3 signals with a total bandwidth of 155.52 Mbps. When the signals get to where they are needed, they are separated or demultiplexed to get back the 3 DS3 signals, which might be constructed of 28 DS1 signals each.

When used to transport data packets instead of telephone calls, the individual channels are generally invisible to the end user, although they exist within the T-carrier and SONET systems. DS1 and T1 can be said to have a bandwidth 1.5 Mbps. DS3 and T3 can be said to have a bandwidth of 45 Mbps. It is these numbers that you can use to compare pricing with competing telecom services , such as Metro Ethernet.