[asterisk-dev] CDR issues - Can someone sanity check them?

[Kevin P. Fleming]

On 01/04/2012 01:32 PM, Ryan Wagoner wrote:

> I understand there is no definition of a transfer CDR. That problem is
> the transfer is not accounted for. For example party A calls party B,
> party B answers, party B attended transfers to party C using a Polycom
> phone. I'm assuming the Polycom phones just calls party C then uses a
> SIP REFER.
>
> This scenario is common as we have a main line that everyone answers.
> They answer, call the responsible party, announce the call, and
> transfer.  The CDR logs leave out that the call was transferred to party C.

I'm not disputing your need for this information; my point is that the 
CDR format, and the fields it contains, pre-dates Asterisk by many, many 
years (maybe even decades), and there aren't any fields available to 
properly represent transfers. In a CDR there is a calling party and a 
called party; if the call from A to B incurred costs for you, *and* the 
call from B to C (later transferred to A) also incurs costs for you, it 
is impossible for a single CDR record to store that information. If the 
call is later transferred to a fourth party, again incurring costs for 
you, the situation just gets worse.

What has been attempted in the past is generating individual CDRs for 
each of these connected-call-leg pairs (A+B, B+C, A+C, etc.) and having 
some sort of unique data in a CDR field that would allow them to be tied 
together in whatever way that your billing system decides to do so. 
However, even that is not without its problems, and even this method of 
using CDRs is very, very close to what CEL does.

> If Asterisk just picked a format to log the transfer CDR that would be
> acceptable. You could always quickly parse the CDR log into the format
> needed. CEL provides way more information than needed and requires a
> more complex parser not to mention data storage. For the last year I
> have 1GB of CDR data in mySQL with 4.5 million rows. I'm guessing CEL
> would be 4-5 times this.

'Asterisk' can't pick anything, it is a piece of software... so to 
properly state your request, if the "users of Asterisk convinced the 
Asterisk developers to pick a format to log the transfer CDR" that would 
be acceptable. Yes it would... except that there is no way to log a 
transfer in a CDR without either losing information, or producing 
multiple CDRs that need to be coalesced in some sort of post-processing 
step.

-- 
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
Jabber: kfleming at digium.com | SIP: kpfleming at digium.com | Skype: kpfleming
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
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