T-1 Cas - wink start

Unanswered Question
Jul 15th, 2008

I'm trying to receive an 800 number over a T-1 CAS with the carrier sending me the last four digits as the dnis. When I call the number I get dead air. My carrier says they aren't getting a wink back from my equipment. Here is my config on the T-1 controller T1 0/0/0

framing sf

linecode ami

cablelength short 133

ds0-group 0 timeslots 1-24 type e&m-wink-start

description BROADWING LD T1: 0040121319

Any help would be appreciated.



I have this problem too.
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Paolo Bevilacqua Tue, 07/15/2008 - 09:55

Hi, first of all pls post "show controllers T1" because AMI/SF are a bit surprising to be still around these days.

After that it can be a simple issue as tuning timings.

Paolo Bevilacqua Wed, 07/16/2008 - 06:50

Hi, circuit is fine. Try:

voice-port 0/0/0

timing wait-wink 1200

If no changes, configure "service timestamps debug msec", then take "debug vpm signal" with "term mon" for incoming call.

dfhensley Wed, 07/16/2008 - 07:08

Same result after I added the timing wait-wink 1200. I then configured debug and ran the debug vpm signal and called the number. I have attached the debug output.

Thanks again for the help!


Paolo Bevilacqua Wed, 07/16/2008 - 07:13

Hi, please configure "service timestamps debug datetime msec" and take the trace again.

Please use .TXT only as that format is hard to read due to line truncation.

Paolo Bevilacqua Wed, 07/16/2008 - 08:10

Hi, something is happening here:

Jul 16 15:23:30.709: htsp_process_event:[0/0/0:0(5), EM_WAIT_SETUP_ACK, E_HTSP_PROCEEDING]

Jul 16 15:23:30.709: htsp_process_event:[0/0/0:0(5),EM_WAIT_SETUP_ACK,E_HTSP_RELEASE_REQ]em_wait_setup_ack_release em_onhook (0)vnm_dsp_set_sig_state:[recEive and transMit0/0/0:0(5)] set signal state = 0x0

Apparently the received off-hook is very short - 8 msec. Can you ask which wink timing they're using ? Also which exact IOS are you using ?

EDIT: for reference below a normal E&M "handshaking" until to the point where DNSI digits are received:

Jul 16 08:47:41.593: htsp_process_event: [0/0/0:0(7), EM_ONHOOK, E_DSP_SIG_1100]em_onhook_offhook

Jul 16 08:47:41.593: htsp_timer - 3000 msec

Jul 16 08:47:41.597: htsp_process_event: [0/0/0:0(7), EM_WAIT_SETUP_ACK, E_HTSP_SETUP_ACK]em_wait_setup_ack_get_ack

Jul 16 08:47:41.597: htsp_timer_stop interdigit timer cfgd to 3000

Jul 16 08:47:41.597: htsp_timer2 - 176 msec

Jul 16 08:47:41.773: htsp_process_event: [0/0/0:0(7), EM_WAIT_SETUP_ACK, E_HTSP_EVENT_TIMER2]em_wait_prewink_timer

Jul 16 08:47:41.773: em_offhook (0)vnm_dsp_set_sig_state:[recEive and transMit0/0/0:0(7)] set signal state = 0x8em_onhook (200)vnm_dsp_set_sig_s tate:[recEive and transMit0/0/0:0(7)] set signal state = 0x0

Jul 16 08:47:41.773: htsp_timer2 - 10000 msec

Jul 16 08:47:42.177: htsp_digit_ready: digit = 2A

Jul 16 08:47:42.177: htsp_process_event: [0/0/0:0(7), EM_OFFHOOK, E_VTSP_DIGIT]em_offhook_digit_collect

Jul 16 08:47:42.177: htsp_timer_stop2

dfhensley Wed, 07/16/2008 - 09:14

IOS is 12.4(11) and the carrier wink was 6 seconds he increased it to 10 seconds, but says that he is getting our wink back in 11 seconds. Can the equipment be set to send wink quicker?

Again I really appreciate all the help!


Paolo Bevilacqua Wed, 07/16/2008 - 09:41


router is supposed to send wink in 180 - 200ms as you can see from the successful trace above.

The wink at 11 sec they're seeing is an absolute anomaly.

What is happening is something abnormal after 8msec.

Can you upgrade to 12.4(11)XJ4 ?

Note: if they could switch you to PRI instead you would be up and running already. T1 CAS can be challenging sometime.

dfhensley Wed, 07/16/2008 - 10:06

Why are you suggesting upgrading the IOS? Would that resolve this issue?



Paolo Bevilacqua Wed, 07/16/2008 - 09:46

It's all defaults and that's ok.

You can reset wait-wink to default, beside it's important only for outgoing.

Conversely wink-wait is the time before sending wink on incoming.


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