Streamyx

Delivery of dedicated bandwidth services to meet business data network requirements is evolving at breakneck speed (no pun intended). But that doesn't mean your options are limited. In fact....it really creates more opportunity to be creative.

Case in point is set up of DS3 connectivity for local loops.

According to my knowledge nowdays most of the DS3 drops are connected by fiber. But is that description entirely accurate?

DS3 hand-off is always done as copper. However, I've never heard of any LEC stringing coax DS3 cables across telephone poles; the coax DS3 is used within the building where the hand-off takes place.

To ride between buildings (e.g. to the CO), DS3 is muxed-up to OC3 or higher. This means that to get a single DS3 into a building with no fiber yet, the LEC will trench fiber into the building and install an OC3 mux...very expensive.

DS3's themselves are definately copper (Coax w/BNC connectors).

They commonly are brought in via a SONET Fibre system (aka. a single channel on an OC3/STS-1). Thus perhaps the confusion.

If you require more than 1 DS3, the provider will usually drop an OC3/OC12 SONET MUX/ADM on your premises; and mux the multiple DS3's into a SONET/OC3-OC12 signal for delivery into the Telco Metro Network.

However, "your" interface (i.e. your side of the DEMARC) is always Coax/BNC, one pair of coax (Tx/Rx) per DS3. The fact that the local telos may employ a SONET/Fibre facility is irrelevant to you for all intents and purposes.

The only Caveat to that, is if you *also* have your own SONET ADM/MUXing equipment. You could request 3 x DS3's, but ask that the Telco bring it in on a channelized OC3 (3 x STS-1's); and you would DEMUX the DS'3s from the SONET signal yourself.

This is what quite a few business do - for example they may have a bunch of Nortel OM3500 OC-48 Transport Nodes, and usually request their carriers to drop any leased DS3's to them on SONET APS 1+1 OC3/OC12 links; after which they can then run protected SONET/Fibre to their equipment.

These businesses would then Mux/Demux the DS3's themselves. However, the *all* still terminate as individual Coax/BNC connections on their own internal DSX-3 termination panel.

So....yes both copper and fiber are involved in obtaining a DS3. But the exact configuration is not as limiting as it may appear....and creativity in a final solution is definitely possible.

Michael is the owner of FreedomFire Communications....including DS3-Bandwidth.com and Business-VoIP-Solution.com. Michael also authors Broadband Nation where you're always welcome to drop in and catch up on the latest BroadBand news, tips, insights, and ramblings for the masses.