[asterisk-dev] The New CDR system

Tim Panton tim at mexuar.com
Sun Apr 1 01:15:16 MST 2007

On 31 Mar 2007, at 17:17, Rod Dorman wrote:

> On Saturday, March 31, 2007, 09:43:53, critch wrote:
>> On Sat, 2007-03-31 at 10:59 +0300, Tzafrir Cohen wrote:
>>>    ...
>>> But CDR data really needs what TCP has to offer.
>>> What you do is re-implement TCP (or TCP/with a bit of SSL). While it
>>> might work, ,it is not as good as the original.
>> The only thing needed is guarenteed delivery. IAX full frames in UDP
>> already do that. Seems to work fine for most people.
> I can understand Tzafrir's point of view. The IAX2 protocol draft  
> states
>      "Full frames are sent reliably, so all full frames require an
>      immediate acknowledgment upon receipt"
> whereas  TCP  utilizes a sliding window protocol that doesn't  
> require an
> ACK for every individual transmission.

Actually if you cared to it would be legitmate for an IAX implementation
to ACK a number of fullframes by just acking the _last_ one, this
implicitly acks all the earlier full-frames in that call.

IAX is more like TCP in this respect than it is similar to other UDP
protocols (SNMP for example) where indeed each packet needs its own


Tim Panton


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