Adsl Ber Error Start Test
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enable scripting. ADSL statistics This page shows the signal attributes of the gateway's ADSL connection. At the bottom of this page, there is a button for running an ADSL bit error rate calculation BER Test (bit error rate). This test determines the quality of the bit error rate test ADSL connection. There is information on this test below the table describing the fields. This table describes the bit error rate example fields on the page: Mode: This is the modulation protocol — G.DMT, T1.413, or G.lite. Type: The channel type, which can be Interleave or Fast. Line coding: This indicates whether
Bit Error Rate Vs Snr
Trellis coding is off or on. Status: This is the status of the DSL link. Link power state: Displays the power management state of the ADSL connection. SNR margin (dB): This is a signal-to-noise ratio (SNR) margin for traffic going in both directions. Attenuation (dB): An estimate of the average loop attenuation downstream and upstream. Output power (dBm): The total bit error rate pdf output power in both directions. Attainable rate: This is the maximum achievable downstream rate. Rate (Kbps): The actual rate at which data is flowing in both directions. K: This is the number of data bytes in an ADSL data frame. R: The number of redundant check bytes per Reed-Solomon code word. S: The length of the Reed-Solomon code word, in data frames. D: The interleaver depth. Delay: The delay, in microseconds, of the ADSL connection. Super frames: This is the total number of super frames. Super frame Errors: The number of super frames received that had errors. RS words: This is the total number of Reed-Solomon code words. RS correctable Errors: The number of Reed-Solomon code words with correctable errors. RS uncorrectable Errors: The number of R-S code words that had uncorrectable errors. HEC Errors: The total number of header error checksum errors. OCD Errors: The number of out-of-cell delineation errors. LCD Errors: The total of lost-cell-delineation errors. Total Errors: The total number of errors. Data Cells: The number of data cells. Bit Errors: The number of bit e
be challenged and removed. (March 2013) (Learn how and when to remove this template message) In digital transmission, the number of bit errors is the number of received bits of a data stream over a communication channel that have been ber repair altered due to noise, interference, distortion or bit synchronization errors. The bit error rate
Ber Meaning
(BER) is the number of bit errors per unit time. The bit error ratio (also BER) is the number of bit errors
Bit Error Rate Matlab
divided by the total number of transferred bits during a studied time interval. BER is a unitless performance measure, often expressed as a percentage.[1] The bit error probability pe is the expectation value of the http://support.usr.com/support/9113/9113-ug/status_adsl.html bit error ratio. The bit error ratio can be considered as an approximate estimate of the bit error probability. This estimate is accurate for a long time interval and a high number of bit errors. Contents 1 Example 2 Packet error ratio 3 Factors affecting the BER 4 Analysis of the BER 5 Mathematical draft 6 Bit error rate test 6.1 Common types of BERT stress patterns 7 Bit error rate tester https://en.wikipedia.org/wiki/Bit_error_rate 8 See also 9 References 10 External links Example[edit] As an example, assume this transmitted bit sequence: 0 1 1 0 0 0 1 0 1 1 and the following received bit sequence: 0 0 1 0 1 0 1 0 0 1, The number of bit errors (the underlined bits) is, in this case, 3. The BER is 3 incorrect bits divided by 10 transferred bits, resulting in a BER of 0.3 or 30%. Packet error ratio[edit] The packet error ratio (PER) is the number of incorrectly received data packets divided by the total number of received packets. A packet is declared incorrect if at least one bit is erroneous. The expectation value of the PER is denoted packet error probability pp, which for a data packet length of N bits can be expressed as p p = 1 − ( 1 − p e ) N {\displaystyle p_{p}=1-(1-p_{e})^{N}} , assuming that the bit errors are independent of each other. For small bit error probabilities, this is approximately p p ≈ p e N . {\displaystyle p_{p}\approx p_{e}N.} Similar measurements can be carried out for the transmission of frames, blocks, or symbols. Factors affecting the BER[edit] In a communication system, the receiver side BER may be affected by transmission channel noise, interference, distortion,
to transmit digital data over the telephone line between our home and the exchange. Unlike cable broadband which uses specially laid optical fibre to the premises and forms part of http://www.kitz.co.uk/adsl/adsl_technology.htm a larger network, ADSL utilises existing telephone cable to bring broadband to the home. How http://www.cisco.com/c/en/us/td/docs/ios/12_0s/feature/guide/bert.html does adsl work - on the line. What is modulation? What is DMT? How does DMT work? What frequencies are used? VDSL2 tones in use. Tones which aren't in use. What are Tones, carriers, buckets, bins? Initialisation and Synchronisation Bit Loading Bit Allocation Bit Allocation Table What is Bit Swapping? What is Bit Error Rate (BER)? Bit Allocation and Power Cut Back Bit bit error Allocation and Low SNR Bit Allocation and Long Lines What is Seamless Rate Adaption (SRA)? ~ How does adsl work - 'on the line'. Telephone lines can be used to convey analogue signals and the copper pair has the ability to carry a range of frequencies. DSL makes use of the fact that voice signals for telephone devices are all under 4kHz, and utilises the previously unused higher frequencies to transmit data. An adsl splitter is used bit error rate in the home to separate the telephony and adsl signals and to help ensure that telephony devices don't use any of the frequencies used by ADSL. ADSL1 and ADSL2 utilise frequencies up to 1.1 MHz ADSL2+ utilises frequencies up to 2.2 MHz VDSL2 utilises frequencies up to 17.664 MHz DSL uses a technology called Frequency Division Multiplexing (FDM) which means it combines multiple frequency signals onto a single carrier wave over a shared medium such as cable, wire or fibre. Several years ago it was not unusual to hear BT engineers refer to DSLAMs at the exchange as a "Mux" or Multiplexor - DSLAM stands for Digital Subscriber Line Access Multiplexer. ~ What is Modulation? Because our computers use digital data a MODEM (MOdulator-DEModulator) is needed to code and decode between digital and analogue signals. The method of converting digital data into analogue signals which can be carried over the copper wire is known as Modulation. Our modem/routers and the DSLAM at the exchange are the hardware equipment that perform modulation. There are different methods of modulation, but the common standard used for ADSL is called DMT. Variations on the basic DMT modulation may be used depending upon the adsl type, but the basic theory remains the same. Type Standard Modulation Tech Notes ADSL1 G.992.1 g.DMT DMT standard for adsl1 ADSL2 G.992.3 g.DMT.bis Improved
IOS and NX-OS SoftwareCisco IOS Software Releases 12.0 SConfigureFeature Guides Bit Error Rate Testing Download Print Available Languages Download Options PDF (492.0 KB) View with Adobe Reader on a variety of devices Updated:May 27, 2008 Bit Error Rate Testing Table Of Contents Bit Error Rate Testing Contents Feature Overview Performing a BER Test BERT Patterns Supported Benefits Restrictions Related Features and Technologies Related Documents Configuration Tasks Performing a BER Test on a T1 Line Terminating a BER Test on a T1 Line Verifying a BER Test on a T1 Line Performing a BER Test on a DS3/E3 Interface Terminating a BER Test on a DS3/E3 Interface Verifying a BER Test on a DS3/E3 Interface Monitoring and Maintaining BER Tests Configuration Examples Additional References Standards MIBs RFCs Technical Assistance Command Reference bert pattern interval show controllers Glossary Bit Error Rate Testing This feature module describes how to configure a bit error rate test (BERT) and display the test results for channelized line cards in Cisco internet routers. History for the Bit Error Rate Testing Feature Release Modification 12.0(14)S This feature was introduced with six-port Channelized T3 line cards in Cisco 12000 series Internet routers. 12.0(17)S12.0(17)ST This feature was introduced with two-port Channelized OC-3/STM-1 line cards in Cisco 12000 series Internet routers. 12.0(21)S12.0(21)ST This feature was introduced with four-port Channelized OC-12/STM-4 line cards in Cisco 12000 series Internet routers. 12.0(21)S BERT pattern enhancements were added on six-port Channelized T3 line cards in Cisco 12000 series Internet routers. 12.2(28)SB This feature was integrated into CiscoIOS Release 12.2(28)SB. 12.0(33)S This feature was integrated into CiscoIOS Release 12.0(33)S. Finding Support Information for Platforms and Cisco IOS Software Images Use Cisco Feature Navigator to find information about platform support and CiscoIOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructio