FTC disclaimer: This post contains affiliate links and I will be compensated if you make a purchase after clicking on my link.
SDSL is generally in demand for small businesses that can support data speed of up to 3 Mbps through a single pair of copper wire.
Moreover, we cannot use SDSL on the same telephone line from which we are availing conventional voice services.
Let’s look into what symmetric DSL means and the SDSL speed you can get. Further, we will see how SDSL is different from ADSL and SHDSL.
What is Symmetric DSL?
Symmetric Digital Subscriber Line (SDSL) is based on DSL technology that allows symmetric bandwidth on the downstream and upstream and enables data transfer on a single copper line.
Moreover, Symmetric Digital Subscriber Line (SDSL) technology provides high-speed internet services over copper wire.
SDSL is also referred to as “Single-line DSL” because it uses single twisted-pair copper wire.
How Does SDSL work?
SDSL working mechanism and implementation are very similar to High-bit Rate Digital Subscriber (HDSL) and Asymmetric Digital Subscriber Line (ADSL).
Moreover, it is based on the same algorithm (2B1Q) used by HDSL and ISDN (Integrated Services Digital Network) circuit.
SDSL transfers data over one pair of copper wires, and the transmission rate is up to 2 Mbps, which is very similar to HDSL circuits.
The transmission speed of data downstream and upstream is the same in both directions.
The transmission speed will vary if it exceeds 3000 meters and the quality of the circuit is not good.
Difference between SDSL and ADSL technology
ADSL technology has a downstream speed more than an upstream speed, whereas SDSL has the same transmission speed in both directions.
ADSL supports both the telephone line service and internet service simultaneously, but SDSL allows only data service with a given copper wire pair.
Moreover, ADSL is not ideal for businesses because if the companies require good upstream data like uploading files and video conferencing, they will struggle along the way.
Whereas SDSL guarantees the same downstream and upstream data speed, which is suitable for businesses.
ADSL bandwidth decreases with distance, whereas in SDSL, distance doesn’t affect the bandwidth only if not exceeded the pre-defined length.
Additionally, SDSL service is “always available,” which means that there would be no disconnection and reset of the service. But, the only exception is at the time of reconfiguration or troubleshooting.
Whereas SDSL service is no guarantee to have always-on services. So it is not aimed for business purposes instead ideal for home users.
Lastly, SDSL is more expensive than ADSL because it provides dedicated data connections without compromising bandwidth.
What are the maximum SDSL speeds you will get?
SDSL speeds vary depending on the subscription level and the limitation put by service providers.
However, SDSL speed ranges from 72 kbps to 2.3 Mbps. But, the average speed of SDSL is somewhat 1 to 1.5 Mbps.
Where will you get SDSL service?
Most larger ISPs or telephone companies in the United States like Verizon, AT&T, and Sprint provides SDSL services.
It is also available in other parts of the world like North America, South America, Europe, and some parts of Asia.
In Europe, SDSL standard changes because of which they have different equipment.
Currently, SDSL service is growing fastly in most parts of Asia because of its huge popularity.
How is SHDSL different from SDSL?
SHDSL stands for Single-pair High-Speed Digital Subscriber Line.
Both SHDSL and SDSL are based on the same technology, but SHDSL delivers a faster data transmission rate.