先决条件 – 数字用户线路 (DSL)
ADSL代表非对称数字用户线，而VDSL代表极高比特率数字用户线。
主要在信息传输速度或速率方面存在分歧，其中 VDSL 比 ADSL 快得多。
我们来看看ADSL和VDSL的区别：
| S.NO | ADSL | VDSL |
|---|---|---|
| 1. | ADSL stands for Asymmetric digital subscriber line. | VDSL stands for Very High Bitrate Digital Subscriber Line. |
| 2. | It uses either Carrier-less Amplitude Phase or Discrete Multitone Technique for modulation. | While it uses Discrete Multitone Technique for modulation. |
| 3. | It uses Point-to-Point protocol rather than Asynchronous Transmission Mode protocol. | While it uses Asynchronous Transmission Mode protocol. |
| 4. | The coverage of ADSL is 18000 feet. | While the coverage of VDSL is 4500 feet. |
| 5. | The vary of upstream rate of ADSL is from sixty four Kbps to 1Mbps . | Whereas the vary of upstream rate of VDSL is from 1.5 Mbps to 2.5 Mbps . |
| 6. | The vary of downstream rate of ADSL is from five hundred Kbps to 8Mbps. | While he vary of downstream rate of VDSL is from fifty Mbps to fifty five Mbps. |
| 7. | ADSL provides the data service and POTS service. | It also provids the POTS service as well as symmetric data service. |