Posted by: Mudassir Ali | May 28, 2010

PCM Capture

Currently Being Moderated

PCM Capture

Q.) How to Do it ?

Ans.) The PCM capture procedure is fairly straightforward.

The steps are as follows:
1. Enter configure terminal mode on the GW.
2. Enter “voice hpi capture buffer 5000000” to configure the capture buffer.
3. Enter “voice hpi capture destination flash:pcm.dat” to specify the destination file.

Once you have the above configured you are ready to capture the PCM stream
from the router. Reproduce the issue.

1. Enter “show call active voice brief” and determine what voice port a trouble call is using. “show voice call sum” will also show what ports are in use.
2. Enter “test voice port x/y/z pcm-dump caplog 7” where x/y/z is the number of the port that has the problem call up.

You can check the status of the capture using the following command:
sh voice hpi capture

This will show you the following output:
HPI Capture is on and is logging to URL
11196 mesages sent to URL, 0 messages dropped
Message Buffer (total:inuse:free) 3048:0000:3048
Buffer Memory: 999744 bytes, Message size: 328 bytes

If the number of “messages sent to URL” is increasing at a steady state then the capture is working properly. If it is not, something is not working properly.

When you are done capturing, just enter configure terminal again and do the following:
no voice hpi capture destination flash:pcm.dat
no voice hpi capture buffer 5000000

Do a dir flash: and get the “pcm.dat” for analysis?

Q.) How to Decode a PCM capture ?

Ans.) Please contact TAC


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s


%d bloggers like this: