[asterisk-users] Simple CDRs

[Anthony Francis]

Tilghman Lesher wrote:
> On Friday 09 January 2009 13:52:56 Anthony Francis wrote:
>   
>> Tilghman Lesher wrote:
>>     
>>> We are entirely interested in DETERMINISTIC methods of uniqueness, not
>>> random and hope-for-the-best.  Given a truly random generator, it is
>>> possible for the same number to come up 100 times in sequence.  That is
>>> part of what random means.  It may be statistically unlikely, but it is
>>> just as likely as any other sequence.  When it comes to fragility, using
>>> a random number for a UUID is NOT deterministic and MAY produce
>>> collisions.
>>>       
>> I may be over simplifying but I would have a serial number object that
>> gets incremented anytime it is called and will be set to 0 at start-up.
>> I would then use it to generate a UUID like this:
>> MAC.serialid.64bit timedate
>>
>> Not only would this number be perfectly universally unique (as long as
>> you dont falsify the MAC) but from a record standpoint it gives you
>> easily parsable information in a single field, the id of the call for
>> referential integrity, the machine that generated the uuid, the calls
>> created since start at the time of the call creation, and the exact time
>> of creation with microseconds.
>>     
>
> Of course, one of the problems comes in with:  what do you do for machines
> which don't have a MAC address?  We've been approached by individuals who
> use virtualized network addresses and don't have direct access to their MAC
> address (which is somewhat important for things like G729 licenses).  What do
> you do for them?
>
>   
In cases of virtualization, at least in xen you can give a virtual 
machine access to a physical card, if not, then fake it using a fake mac 
address on each virtual machine in the research range of addresses, 
after all, you only really care about not conflicting with UUIDs in your 
own system.

Anthony