Troubleshooting example of POS swiping card-- POS swiping failure caused by EC configuration
Reason: POS card swiping failure caused by EC configuration
Failure phenomenon: failed to swipe the card
Device packet prompt message: media analysis on the pos side
Phenomenon 1: discontinuous loss of pos data, media information on the device side of pos card swiping failure
Phenomenon 2: pos swipe card normal packet
Reason analysis: by parsing the packet information, you can see that the data of the POS machine is interrupted and discontinuous after passing through the device. The specific reason is that because the EC on the device is enabled, some of the data is regarded by the DSP of the device as echo cancellation resulting in data loss, and the pos card swiping failed.
Handling measures: for pos services, the detection IP tone switch needs to be enabled.
AIM > voip dsp vbd tdm-ip-auto / / enable the tone detection switch on the IP side. If the device detects the tone,DSP on the ip side, it will automatically turn off the ec configuration.
Remarks:
1, high-speed fax machine and high-speed modem at the beginning of the fax and modem will be reported with phase reversal of the 2100HZ signal, the difference is that the fax will be reported after the V21Flag signal, the role of changing the parameters is to detect a phase reversal of the 2100HZ signal to start a timer, if the timer timeout before the V21Flag signal, it is considered to be a fax, if the timeout is reported to the modem. The timer recommends 10s, as shown in the figure
2. Data services include low-speed data services (fax) and high-speed data services (high-speed fax, pos services, etc.). For high-speed data services, the EC/VAD/CNG of the equipment and other functions that may affect the original signal have little impact on the low speed.
3. Description of pos interaction process:
A. When pos swipes the card, the device sends the originating call to the platform (sip/mgcp/h348, basic call flow).
B. After the platform is connected, start pos data exchange in the media channel (because pos data is high-speed data, before pos data exchange, you need to send a 2100HZ signal with phase reversal. After the device detects this signal, you need to turn off EC/VAD/CNG and other functions that may affect the signal.)
C. Pos signaling interaction process after the platform is connected
