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This page presents information about data transmission in both the transmit and receive directions of communication. You receive information about the quality of the line, and meters are displayed for error events on the ADSL layer.

Click on the "Refresh" button to view the current values.

Negotiated Connection Properties

Max. DSLAM throughput Highest possible speed of data transmission at the DSL exchange (DSLAM). Given in kilobits per second (kbit/s).
Min. DSLAM throughput Lowest possible speed of data transmission at the DSL exchange (DSLAM). Given in kilobits per second (kbit/s).
Attainable data rate The maximum volume of data that can be sent on the line. Given in kilobits per second (kbit/s).
Current throughput The bit rate actually configured on the line. This is the speed at which the data are transmitted over the line. Given in kilobits per second (kbit/s).
Min. effective data rate

This value is displayed only when G.INP is switched on (see below).

The effective data rate is the data rate than can be effectively used. The more defective DSL packets have to be sent repeatedly, the lower the effective data rate.

The Min. effective data rate is the lowest effective data rate since data recording started.

Seamless Rate Adaptation Technology for ADSL2+ that adjusts the speed of data transmission to the transmission quality of the DSL connection without re-synchronizing the DSL connection. This process is switched on or off at the DSL central exchange (DSLAM). When it is switched on, the FRITZ!Box will use it.
Energy-saving mode L2 Power-saving function of ADSL2+. When it is active, it reduces power when the DSL line is subject to no or little use. This function is switched on or off at the DSL exchange (DSLAM). When it is switched on, the FRITZ!Box will use this function.
   
Latency The time that a symbol word needs to arrive completely at the other end of the transmission path (DSLAM or modem). Given in seconds (s).
Impulse Noise Protection (INP) Impulse noise protection: The higher the value displayed here, the lower the impulse noise.
G.INP Protection from impulsive noise by retransmitting on the physical layer in accordance with ITU-T G.998.4. The FRITZ!Box negotiates with the central switching station of the internet provider about whether G.INP is enabled or disabled.
   
Signal-to-Noise Ratio Margin Rate by which the signal can become weaker before an error rate of 10-7 occurs. Given in decibels (dB).
Bitswap A bit swap makes it possible to adjust data transmission to changing line conditions by redistributing the bits over the carriers. Data throughput remains unchanged in a bit swap. If a bit swap is needed, its performance is negotiated with the telephone exchange.
Line attenuation Rate by which the signal is attenuated during transmission. Given in decibels (dB).
Line Branching

The "Line Branching" entry is displayed only if branched lines were detected.

Line branching is when there are branches in the telephone cabling between the DSL mulitplexer (DSLAM) and the FRITZ!Box. Whenever the FRITZ!Box detected branching, the number of branches found is displayed here.

Line branching is also displayed in the diagrams on the "Specrum" tab.

Line branching has detrimental effects on the quality of the DSL connection.

Power reduction

This is a characteristic of ADSL lines only.

If the communication between the modem and DSLAM is good, for instance because they are located very close to each other, the power can be cut back to reduce the minimum energy requirement and minimize interference in cables in the vicinity.

approximate line length The approximate length of the line between the DSL multiplexer (DSLM) and the FRITZ!Box. Given in meters (m).
   
Profile

This is a characteristic of VDSL lines only.

During the synchronization of the VDSL line, a VDSL profile is negotiated. A VDSL profile specifies the following parameters: bandwidth (MHz), tones, interval (kHz), transmission power (dBm) and maximum data rate.

G.Vector G.Vector is an option on VDSL lines. The display here indicates whether vectoring is supported on the VDSL connection.
   
Carrier record This value indicates which handshakes are used for Annex J or VDSL

 

Error Counter

Errored Seconds (ES)  
Errored Seconds (ES) ES stands for "Errored Seconds". This value indicates the number of seconds during which transmission errors occurred. The seconds are counted starting from when the DSL connection is established.
many errors (SES) SES stands for "Severely Errored Seconds". This value indicates the number of seconds during which many transmission errors occurred.
   
Unrecoverable Errors (CRC) CRC stands for "Cyclic Redundancy Check". The check sum of the superframe transmitted by the remote party does not correspond to the sum calculated locally. Possible cause: Disturbances on the line.
per minute Average number of unrecoverable errors per minute.
last 15 minutes Number of unrecoverable errors within the last 15 minutes.
   
corrected DTU DTU stands for Data Transfer Unit. Data transfer units are DSL packets sent between the transmitter and the receiver. Corrected DTU are packets that were damaged during transmission, but which were recalculated by the receiver using a checksum for lossless correction.
per minute Average number of corrected DTU per minute
last 15 minutes Number of corrected DTU within the last 15 minutes
   
uncorrected DTU DTU stands for Data Transfer Unit. Data transfer units are DSL packets sent between the transmitter and the receiver. Uncorrected DTU are packets that are retransmitted because they were damaged during transmission.
per minute Average number of uncorrected DTU per minute
last 15 minutes Number of uncorrected DTU within the last 15 minutes