First test for fast-tech Netcom ADSL2 + (1)

ADSL has become the main force for home broadband access. Currently, most users use the first-generation ADSL access technology. With the maturity of the second generation of ADSL access technology, ADSL2 + has begun to embark on a commercial journey. China Netcom and China Telecom have invested heavily in creating the ADSL2 + network to enrich the use of home broadband access to users. As a lucky person, I have the honor to try the second generation of China Netcom ADSL Access Network (ADSL2 + for short ). Compared with the first-generation ADSL access technology, ADSL2 + has a significant improvement in download speed.

For ordinary users, ADSL2 + is still a strange face. What is ADSL2 +? Let's take a look at what ADSL2 + access technology is.

ADSL2 + Access Technology Overview

The G992.5 standard used by ADSL2 + is further extended based on the G.992.3 standard used by ADSL2, mainly to extend the spectrum range from 1.1Mhz to 2.2 Mhz, the maximum number of subcarriers is also increased from 256 to 512. ADSL2 + supports a net data rate of up to 16 Mbps and up to 1024 Kbps. Theoretically, the maximum downlink rate of ADSL2 + can be as high as 24 Mbps, and the maximum uplink rate is as high as 1 Mbps. ADSL2 + breaks the bandwidth limit of the ADSL Access Mode and makes its application more extensive.

The advantages of ADSL2 + are not only the improvement in download speed, but also the great improvement in access distance. The traditional ADSL system has a maximum coverage of about 3 km, which means that the distance between the ADSL user and the local data center of the network operator cannot exceed 3000 meters. If the line is damaged or noise is disturbed, the ADSL coverage will be smaller. The maximum coverage of the ADSL2 + system reaches 6 km, which will enable more users to enjoy the cheap and efficient access mode of ADSL2 +.

Appearance of the Second Generation ADSL cat

Today, with more and more network applications, traditional ADSL cannot meet the requirements of home users. The emergence of ADSL2 + can meet users' needs for a wide range of network applications. The ADSL2 + and ADSL use the same copper telephone connection mode. The network operator can complete the smooth upgrade of ADSL2 + by upgrading the local IDC equipment and the client's ADSL cat.

ADSL2 + trial Evaluation

To upgrade to ADSL2 +, you only need to replace the ADSL cat at home. In terms of appearance, there is no difference between the cat of ADSL2 + and that of ADSL. You can see the difference only when you log on to the management interface.

Modulation status setting for ADSL2 + cats

It is not difficult to see that the cats of ADSL2 + are somewhat different from those of the ADSL generation. The most intuitive feeling of upgrading to ADSL2 + is that the network transmission speed has been significantly improved.

Because the author's ADSL2 + network is in the internal test phase, the downlink speed is changed from 2 Mbps to 10 Mbps. Note: The speed-up test has just been conducted to 10 Mbps ), the uplink speed is adjusted from Kbps to 1 Mbps. After the network is upgraded to ADSL2 +, the most direct change is that the download speed is significantly improved.