[VoiceOps] Geographic redundancy

Alex Balashov abalashov at evaristesys.com
Wed Aug 12 10:13:59 EDT 2009

Jason Vanick wrote:
>>> No, not sure how you got this idea, you think every mid-sized ISP in the 
>>> '90s had connections to the service control points? For a CLEC to get a 
>>> lot of the O/T benefits SS7 interconnection would be desirable, but not 
>>> required.
>> That's true.  I was assuming we were talking about telephony here 
>> strictly.
>> There are a few uses ISPs have for CLEC licenses that have nothing to do 
>> with phone.  One is rights-of-way for network build-out, pole 
>> attachment, etc.  Another is getting UNE rates on leased circuits 
>> instead of wholesale access rates.  That still required interconnection 
>> and/or CO colocation for aggregation, but not SS7.
> There were 2 other good reasons to have a clec license, at least in the 
> rate-center type latas... (Chicago/Lata 358 comes to mind)...
> 1. was to play the reciprocal comp game with the ILEC...  At least one CLEC's
> entire business model was nearly completely based on this early on (Focal Communications)

Ha!  Oh, yes, the good ol' reciprocal comp. arbitrage.  :-)  Some of 
them were practically giving away bulk PRIs to ISPs... didn't matter, 
it's the reciprocal compensation that counts.

> 2. was to have a folded modem pool where all the rate centers terminated into one
> large modem pool.  It was easy to turn up a few ds3s to a few tandem switches to receive
> inbound calls from a large portion of the lata.  After you got up and running and found the
> 'hot spots' you'd then turn up end-office trunks to each of those rate centers to take
> advantage of the more favorable termination rates for #1.

Yes, but these require SS7 interconnection.  The discussion was about 
applications for a CLEC license by an ISP that isn't connected to the 
ILEC tandems and, therefore, doesn't take phone calls per se.  :-)

> Ah the good 'ol days of the Dial-up isp biz...  I remember 20+ Ascend Max TNT's each humming
> along with 16 inbound PRI's of dial-up...
> If I remember correctly tho, in order to connect to the tandems you had to be able to provide 
> ss7 services.  We got all of our ports out of a DMS500, but I do remember people using something
> from cisco to emulate a switch (SCC maybe?) and back end all the dial traffic into 5800's....

There were lots of switch-lite solutions (signaling gateways) that were 
popular during the dialup boom.  The Cisco PGW was very popular among 
them.  All of these could control media gateways via H.248/MEGACO or 
MGCP, and the TNTs did H.248.  Just very basic SS7 ISUP->media gateway 
control was needed to get modem pools going.

Alex Balashov
Evariste Systems
Web     : http://www.evaristesys.com/
Tel     : (+1) (678) 954-0670
Direct  : (+1) (678) 954-0671

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