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Advantages and Disadvantages of Symmetric DSL Service

What is Symmetric DSL?

Symmetric DSL, also known as SDSL, stands for Symmetric Digital Subscriber Line.   It is a service that offers upstream and downstream data rates at the same speed.   

SDSL is a type of symmetric communication, which involves any telecommunications system whose data speed works the same in both directions. 

All types of DSL connectivity work through ordinary telephone lines to provide users with a high speed Internet connection without disrupting the phone lines or tying them up.  DSL works by sending out digital pulses through the phone lines to provide its customers with fast, reliable Internet service, as long as the customer is located within a reasonable distance to the phone company’s central office. 

Advantages of Symmetric DSL

People like symmetric DSL services because the upstream and downstream data rates match.  Additionally, a solid SDSL connection can often support data rates of 3 Mbps. 

Disadvantages of Symmetric DSL

The majority of people who use the Internet will spend their time surfing the Web and checking their e-mail, which uses the downstream direction of data flow.  Because of this, most regular DSL services offer asymmetric DSL, where the downstream rates are far faster than the upstream rates.  Symmetric DSL offers an equal downstream and upstream rate, and some find that the high upstream rate is not used nor needed.  In this case, the resources would better be utilized in the downstream rate.  

Another disadvantage of SDSL is that it requires a special SDSL modem for the service, which can get costly. 

SBC Yahoo Symmetric DSL Services

SBC Yahoo offers Symmetric DSL services for businesses.  They offer a large variety of packages, ranging in speed and price.  Each SDSL plan will come with matching upstream and downstream speeds, ranging from 144 Kbps to 1500 Kpbs.  All Symmetric DSL packages through SBC come with a free router, free activation, and five static IP addresses.