How does the internet work 16

ADSL2 +: Surfing at up to 16 Mbit / s

ADSL2 +: Surfing at up to 16 Mbit / s
Image: teltarif.de Internet connections based on DSL are standard in many households these days. The technology divides the existing frequency band into different channels for voice and data information, and higher frequency ranges that were previously unused are also used.

One of the means to accelerate the data flow again is the certified ADSL successor standard ADSL2 + (ITU standards G.992.5 and G.992.5 Annex L). DSL stands for "Digital Subscriber Line", the "A" for asynchronous - because this most widespread DSL variant allows data to be received much faster than it is sent. Like the previous ADSL standard, ADSL2 + is based on a double copper wire, but uses the frequency ranges of up to 0.14 MHz for the upstream and up to 2.2 MHz for the downstream, whereas previously only frequencies up to 1.1 MHz were used . Due to the larger frequency range, higher bandwidths can be realized over a relatively short distance. While downstream rates of up to 8 Mbit / s are possible over short distances with ADSL, for example, the newer ADSL2 + variant theoretically achieves up to 25 Mbit / s. In addition, it should be less susceptible to disruptive influences on the DSL signal.

Current ADSL2 + offers

ADSL2 +: Surfing at up to 16 Mbit / s
Image: teltarif.de Such surfing speeds are not achieved in practice. Instead, DSL providers rely on 16 Mbit / s connections. As a rule, they do not show the ADSL2 + technology (or the simple name ADSL) - the corresponding connections are simply marketed under the name DSL.

Above all, if the users are to receive triple-play services such as IPTV or video on demand via broadband access in appropriate quality, even higher data transmission rates are necessary - these are then made possible, for example, by means of VDSL. VDSL connections that achieve up to 50 Mbit / s or more in the downstream, however, are based on a different technology.

When it comes to ADSL2 +, it is clear that the providers offer increased DSL bandwidth in metropolitan areas, but ADSL2 + has never been a beacon of hope for the flat country. Because the longer the line, the stronger the signal attenuation - not significantly less with ADSL2 + than with conventional DSL. The range of ADSL2 + is around three kilometers. From a line length of around six to seven kilometers between the household and the exchange, the classic, slower DSL signal hardly ever reaches the user.

In order to be able to receive data from the Internet at up to 16 Mbit / s, users must have the right hardware - standard for new connections today. Sometimes older DSL modems or routers can also be adjusted to the new requirements by means of a firmware upgrade. It is also possible to connect a conventional DSL modem to an ADSL2 + connection or an ADSL2 + -capable modem to a DSL connection. In both cases, however, the full service is not available to the user.

In a separate guide, we show you how to proceed if the provider does not deliver the promised speed.

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