[Asterisk-biz] Call termination database

Alistair Cunningham acunningham at integrics.com
Thu Feb 17 11:38:39 MST 2005


I agree about the LERG information. It's not really what people here 
would be looking for. What we really need is a mapping of DID ranges to 
IP addresses. LERG contains routing information for the PSTN, not the 
internet. What I was thinking of is much more like E164, and indeed 
there could be an E164 interface to it.

<boring ramble> LERG is also not an easy format to work with. A couple 
of years ago, I had the job of writing code to process LERG files so 
that a telco's voicemail system would be able to set tinkle tone MWI 
anywhere in the NANPA, and by the time you get to all the NPA-NXX splits 
and overlays sorted out, the code becomes fairly convoluted. In some 
places, the LERG ranges go down to individual numbers. I ended up 
storing data in a MySQL database, with Perl import scripts from the LERG 
file. </boring ramble>

Alistair Cunningham,
Integrics Ltd,
Telephony, Database, Unix consulting worldwide
+44 (0)7870 699 479
http://integrics.com/


Kevin P. Fleming wrote:
> alex at pilosoft.com wrote:
> 
>> Telcordia LERG contains the real routing information. For a given 
>> NPA-NXX,
>> it maps into LATA and into OCN. Now, carriers group OCNs into "tiers"  
>> (just groups of carriers with similar rates).  Usually Tier 1 is RBOC,
>> Tier 6 is NECA, and those tiers are uniform across all termination
>> providers. All other "tiers" are subject to individual carrier's
>> termination agreements, and they can be "CLEC", "Cellular", "RBOC
>> Cellular" etc. Those OCN-Tier mappings are somewhat individual among 
>> carriers who sell termination.
> 
> 
> I wasn't considering NANPA as much as I was the rest of the world :-) In 
> NANPA, 99% of the routes are the same cost for nearly everyone (unless 
> you are an OC yourself). Alaska, Hawaii and the Caribbean being the 
> notable exceptions, of course.
> 
> Certainly I could see some value in publishing +1 rates down to NPA-NXX 
> level for certain parts of the country (as you say, NECA routes are a 
> biggie). I don't think we need to try to duplicate much LERG 
> information, though. If I publish a route for +1602, that covers all of 
> +1602 unless there are exceptions listed at a more detailed level (if 
> there were NECA or cellular at-cost routes here, but there aren't). When 
> the routing database is used, if you always do a longest-match-wins, 
> then we don't need to list every single NPA-NXX combination, only the 
> exceptions.
> 
> Same goes for international routes too: +44 is primarily a single rate, 
> except for cellular routes and premium numbers, which can be identified 
> using a prefix string.
> _______________________________________________
> Asterisk-Biz mailing list
> Asterisk-Biz at lists.digium.com
> http://lists.digium.com/mailman/listinfo/asterisk-biz
> 
> 



More information about the asterisk-biz mailing list