| Summary: | ASTERISK-04538: Capi | ||
| Reporter: | Marco Löwl (mloewl) | Labels: | |
| Date Opened: | 2005-07-08 03:44:39 | Date Closed: | 2011-06-07 14:02:52 |
| Priority: | Major | Regression? | No |
| Status: | Closed/Complete | Components: | Core/General |
| Versions: | Frequency of Occurrence | ||
| Related Issues: | |||
| Environment: | Attachments: | ( 0) CxEcho.pdf | |
| Description: | there are two general issues with Asterisk at a first glance: - the tiny issue is that facility selector 6 is used to switch on the echo canceller. Facility selector 8 should be used instead. In our procucts we implemented the LEC as facility selector 6 first, but the CAPI association approved 8 because the 6 was allocated by the CAPI Broadband Extension. We adapted it meanwhile. - it seems that Asterisk doesn't make use of the delivery confirmation for transparent data (see DATA_B3_REQ, delivery confirmation flag). This delivery confirmation is a way to control the queue size for outgoing data and thus to keep a short delay on a connection. For links between ISDN cards this is no issue since they all follow the ISDN clock. But as soon as data from another clock source is involved the ISDN card would buffer data and cause long delays. The delivery confirmation bit just causes the DATA_B3_CONF to be indicated when the last byte of the data block has been sent to the line. The queue size then corresponds to the DATA_B3_REQ's pending at that moment. | ||
| Comments: | By: Marco Löwl (mloewl) 2005-07-08 03:49:12 0:00:36.827 CAPI20_PUT(021) 0x0000 01 00 80 80 3D 04 01 04 07 00 06 00 06 01 00 02 ....=........... 0x0010 00 40 00 .@. --- FACILITY REQ AppID 0x0001 MsgNr 0x043d NCCI: 0x00070401 Facility selector: 0x6 Broadband Extensions/Echo Cancellation Facility parameter (0x6): Function: Enable line echo canceller operation Echo Canceller parameter (0x2): By: Michael Jerris (mikej) 2005-07-08 09:09:44 Can you provide a patch for either of these issues? By: Russell Bryant (russell) 2005-07-08 09:22:58 chan_capi is not a part of Asterisk. Please submit any issues you have with it to their developers. Here is the project web page. https://sourceforge.net/projects/chan-capi/ | ||