Many companies need to communicate quickly with other companies so that business can be done with ease and efficiency.  There are many ways to make this work, and one thing that can be very helpful is a fast internet connection.  A T3 connection will ensure that you have a fast connection.  If you do decide to get a T3 Internet connection for your business, keep in mind that you probably should not enter directly into discussions with a bandwidth provider while deciding your bandwidth requirements. They are likely to be focused on "making a sale" than in helping you with your infrastructure decisions. Instead, seek the advice of an independent unbiased broker.

They can walk you through the process to finding a solution which best makes business sense to you and your organization.

There are some questions that you can ask that will help you in receiving the best connections.  If you have a business, there are many questions about a T3 Connection.  For instance, for your company's specific business applications, how do you decide on how much bandwidth will be necessary? Is it T1, DS3, or OC3 or greater? Do you factor in a reasonable overage to account for potential emergent situations? What modeling approach do you use to calculate your min and max load and thus your supportable need range? How do you decide how much is adequate?

Every analysis might be based on the task concept.  In addition, the specific tasks in any application will likely differ by user type so it is useful to look at the frequency of specific tasks by user group.

Every task can be looked at in terms of time. The best time to define bandwidth requirements is during application development. The reason is that most applications can be tuned to perform with significantly less traffic while still in development, and the traffic is often a good indication of other problems like poor database structure or less than optimal distribution of work.

The second best time is before purchasing an application. Two similar applications will have significantly different WAN performance characteristics and this can be a key decision criteria.

The total time is split among the parts. Before worrying about bandwidth, you should determine just where the time is being spent for each task. Do not consider the user action in the task analysis - their keyboard time is best handled with scripts to eliminate that variable, and output is done when the screen is populated or the printout complete. While there are many "favorite" tools to speed the analysis, it can all be accomplished with a spreadsheet, and a packet capture too. 

While applications vary, most have yet to find the application that improves performance on any task when bandwidth goes above about 750Kb. The majority sees no improvement once bandwidth reaches 200Kb.

Added bandwidth becomes an issue of user count after you face the other problems that are entailed in the services of a T3 Connection.  The majority of applications do not suffer performance drops until total average utilization goes above about eighty percent. The communications aspect is impacted by volume of data moved, amount of communications overhead, background load, packet size, protocol, latency, and bandwidth as well.