T1 and T3 are two common types of digital transmission systems used in telecommunications. AT&T originally developed T1 lines in the 1960s to support telephone service. The service gradually evolved to support both voice and data. T3 lines (also known as DS3) are an enhanced version of T1 that gives better bandwidth. Both T1 and T3 have become popular options for supporting business-class internet service.

Understanding T3 Lines

A T3 line is a point-to-point connection between two sites or between a Phone Company Central office and a business location that provides dedicated high-speed internet connectivity or it can be configured to carry multiple T1’s for voice and data. The T-Carrier system works by multiplexing multiple digital channels. Each channel offers a bandwidth of 64kbps. T1 connections contain 24 channels and offer a speed of 1.544 Megabits per second.

A T3 line is, in reality, a large group of T1 lines. 28 T1 lines are bundled together to create one T3 connection. In other words, 28 bundles of 1.544 Mbps are brought together to offer you a speed of 44.736 Mbps.

How does T3 work?

A T3 line carries 672 channels that each run at 64 Kbps. A T3 connection uses TDM or Time Division Multiplexing to interweave these data channels. A multiplexer is a digital switch that accepts all the channels and gives a singular output. It combines inputs by sending signals from different channels over different time slots, enabling several channels to be carried on the same line.

Initially, a T3 line starts as four T1 lines multiplexed to create a T2 line (this is fairly uncommon in the marketplace). An M13 (Multiplex T1 to T3) multiplexes 7 T2 lines to form the T3 transmission line. With each channel running at 64 Kbps, a speed of 42.924 Mbps is achieved through these multiple layers of multiplexing—additionally, some extra bits signal and control of data transmission.

Fiber optics cables are most common but in some limited instances, a 4 wire twisted pair circuit is possible and is used as the T3 transmission medium. However, the copper signal will not run for more than 50ft. Modern wiring technologies such as coaxial cables and optical fibers are more suitable to carry out T3 data transmission.

Benefits of T3 Lines

Reliability of Service

Reliability of Service

Like T1 lines, T3 lines also establish physical connectivity between the ISP (Internet Service Provider) or the phone company and the end customer location. This makes them highly reliable high-speed internet, data and voice connections.

The T3 internet speed and its reliability are two main reasons why this connection is preferred by large enterprises.

In addition to this, the uptime offered by T3 connections is excellent. This is because the repairs of dedicated connections take precedence over repairs of general or shared internet connections. In case of an outage concerning weather conditions, the T3 lines will be repaired and restored before general internet connections. Therefore, T3 internet speed is preferred by businesses requiring dedicated speed with guaranteed uptime.

Fixed monthly expenditure

With a dedicated T3 line, you pay for dedicated bandwidth, high-speed access, and almost negligible downtime. While it is undoubtedly a premium service, with costs ranging anywhere between $500 – $1500 every month, the expense can be easily managed and budgeted for as it does not vary over time.

Symmetric connection service

Suppose your business requires large file sharing, regular high-volume backups, and constant cloud access. In that case, there is a high possibility you will suffer from slow internet speed while uploading data if you are over a broadband connection.

On the other hand, T3 lines are symmetrical, meaning that they offer the same upload and download speed. Both upload and download can take place at the same time without impacting the performance of one another.

Should I upgrade to a T3 line?

If your business requires high reliability and upload speeds, a T3 line may be a viable solution. Even with newer technologies, customers may still prefer using T1 or T3 lines due to their uptime guarantees.

However, it is important to remember that while T3 internet speed offers amazing support for your business requirements, it can also be quite expensive.

CarrierBid has over 180 carriers and service providers in our partner network. Contact us today for a free consultation (we never charge a fee for our service!) to discuss if T3 Lines are right for you!

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