Message Capture allows you to activate the capture of raw ISDN layer 3 messages between endpoints.

When activated, a small buffer is created in the /var/tmp directory, that stores each message being sent from or arriving on each channel. The buffer is circular, so it wraps around once it is full. When the buffer is full, it makes space by removing as many messages as required to store the next message. Therefore, once the buffer is full, the oldest call may still have some messages, but will probably not be the complete messaging for the call. Once the capture is activated, the user can select any channel to display. The messages are then formatted in a readable form from the stored ASN.1 format. The enable and buffer size settings are stored in the configuration. If the ISDN system restarts and the capture is enabled, the capture starts during ISDN system initialization. This allows capture of all D-channel messaging during layer 3 bring-up. The message capture works regardless of the ISDN settings being a network or client(user).

Enabling this does not cause any services to restart. If there are pending configuration changes, then a network restart will happen. When changing settings on this page, Ribbon recommends that all pending configuration changes be saved beforehand.

Configuring the Message Capture Settings

This section outlines how to configure the Message Capture settings.

This page is active only if T1 is configured for PRI service.

To Configure the Message Capture Settings:

  1. Choose Network > ISDN > Message Capture.

  2. Configure settings using the information in the following table as a guide. When you have finished configuring settings, click Submit.

    Message Capture Parameters

    ItemDescription
    Enable Message CaptureSelect the Enable Message Capture checkbox to enable the ISDN message capture.
    Channel Buffer SizeThis field sets the buffer size for each channel in Kb. Each channel has a separate buffer of this size, so that the total buffer size will be 24(T1) times the channel buffer size. Each enabled T1 will have one of these buffer files.
    Display T1This field shows the number of T1 to display. Only enabled T1 is included in the list box. They can range from 1 to 4.
    Display Channel This field indicates the channel number to display. If T1s are enabled, the list box is populated with 1-24. 
    Display Raw BufferIf this is enabled, the entire raw buffer for the channel is displayed in HEX at the bottom of the formatted messages. The buffer is displayed in natural order, so if the buffer has wrapped, the oldest message will almost never be at the top of the display.
    Request DataOnce the T1 and channel are selected, pressing this button sends a request to the system to return the formatted data. This option is disabled if any configuration changes to the buffer are selected, or any configuration changes are pending.