Tuesday, March 16, 2010

Internet Data Access, a strategy for selecting T1, DSL, or Cable Modem

Internet Data Access, a strategy for selecting T1, DSL, or Cable Modem

The primary difference between DSL and a T1 is in the dedicated bandwidth and level of over subscription that occurs before the service reaches the end user. When you purchase a full T1 of Internet access, you are generally getting access to 1.544 Mbps of transmission on the carrier’s network, regardless of what other customers are transmitting and receiving. To better illustrate this, let’s assume that a carrier has capacity for 150 Mbps at any given time. This means that they would sell is 100 T1s at the most; Tier One carrier networks are seldom oversubscribed. For every megabyte of capacity, they can sell one megabyte access to a customer.

DSL works differently than T1 lines - and costs less - because of over subscription. When you use a DSL connection your service runs through a piece of equipment called a DSLAM, as opposed to running directly into the Internet. The DSLAM acts as a point of aggregation between the DSL subscribers and the direct connection to the Internet (normally a T1 or DS-3). Typical DSL over subscription rates run from 4:1 to 25:1. Or in other words, for every one megabyte of demand coming into the DSLAM, a fraction of that is available. For example, if the Carrier provides a 3.0 Mbps DSL Line to its customer, that line will be shared by 4 to 25 customers, thus allowing .12 Mbps to .75 Mbps per customer. The benefit to this design is that a DSL provider can provide a 3 Mbps connection for a fraction of the T1 price. The disadvantage is that when the DSLAM gets busy, your connection speed will slow considerably.

Each T-1 channel can be used to run both voice and data. For instance you could have four channels dedicated to four different voice numbers with the remainder allocated to data. Virtually any permutation is available. The voice channels simply plug into the phone company's jacks into the channel bank where the voice service is located, and that's it. Many carriers will be able to offer long distance at a very reasonable price as well.

A DSL connection has a low price and is less reliable than a T1 connection. A T1 is much more expensive than a DSL connection but is also much more reliable.

So are you looking for reliability or price? Reliability becomes critical when customers or employees depend on your connection for immediate responses.

If your customers use your connection to access your databases or your server or the Internet then reliability of your connection is critical. If your employees depend on your connections because you host the e-mail server in house or host web servers, your connections is considered critical.

A critical connection can be viewed much like a life line, without which your business would be negatively impacted. Your monthly savings of having a sub-par connections will not make up for the loss in productivity of your employees or loss of customers when your DSL connections gets bogged down or cut off.

The price for T-1’s circuits have dropped dramatically in recent years. Generally, for companies with more than 5 lines, a T-1 circuit will be very cost competitive.

Dan Young is President & CEO of Young Consulting Group, a boutique business consulting firm, focused on helping owners grow their business. Young Consulting Group provides Telecom Consulting services for companies in the Small & Medium Business Sectors. For your FREE Telecom Analysis, call 800.798.7996 or email us at You can also find more Business Growth ideas by going now to

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