Saturday, September 13, 2008

Topology and layout ideas / Idées pour la topologie

I had lunch with Vincent MONVILLE again this week and we talked about some of the fiber details of the project. I was interested in his estimate of installation costs (to see if I've set aside enough) but he explained that first I had to decide exactly how I was going to distribute and split off each connection. Only then would it be possible to get a better grasp on the prices.

He was right so I took out my trusty Garmin GPS III Plus and marked all the handholes specified in the France Telecom map. That allowed me to get a pretty good estimate of the distances from each handhole back to the main aggregation point for telephone lines in our residence.

Handhole distance from aggregation point

Here are the numbers I came out with.

  • Total length of all fiber pair segments to the handhole (handhole to aggregation point): 3934 meters
  • Total length of all fiber pair segments to the house (generous estimate of home/apt to aggregation point): 4719 meters
  • Average loop length to handhole: 79 meters
  • Longest loop length to handhole: 220 meters
  • Shortest loop length to handhole: 19 meters

  • Best aggregation point: In the street next to waypoint #021
Distance from each house to aggregation point

I figure the best way to distribute the 50 lines is using some sort of microconduit within the existing conduit in the street. That way the line would be protected at the split-off points. I'm not sure though so any suggestions would be greatly appreciated.


sbultez said...
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Tad said...


Thank you for the comment. I'm so glad your mom spoke up in the meeting. Otherwise, I don't think we would have ever finished talking about just the roads.

Thank you as well for the link to Jean Michel Billaut's blog. For those not here in France, he's the driving force here in France for fiber. He seems to have really succeeded in raising awareness in government.

Hopefully we'll have some fiber here in the residence soon. I'm just having some trouble figuring out where we can put the aggregation point.

sbultez said...
This comment has been removed by the author.
Tad said...


I think there are two options for bringing the connection to our residence.

1. They build to us.
I think the best way to get an operator to build out to us is by convincing a large majority of the residence to switch over the fiber when it's ready. If we could offer an 80% penetration rate then the operators may find it possible to build out to us. An unbundled line (dégroupée) from France Telecom costs Free and Neuf nearly EUR 10 per month (EUR 400/month for 40 homes) so there is potential for savings. I also plan on extending the footprint out to neighboring residences as soon as we can get ours up and running as an example and "proof of concept". Any operator serving our residence would have easy access to these new areas as well.

I think it could be an interesting trial and opportunity for any of these companies.

2. We build out to the exchange
If we can't convince someone to come to us then we'll have to build out to the exchange (330 meters). The nice thing is the French government just opened up a process for accessing France Telecom's conduit. That would be much more economical than digging the line ourselves. However, in a worse-case scenario I would obtain financing for the dig and charge a fee to operators which would be slightly less than they pay now for a copper line.

The key here again is expanding the footprint to help spread the high fixed costs of the line to the exchange. I would want to branch out and expand to other residences just next to ours since there are many more homes in these areas (not far from ours) which would make interconnection much more interesting for operators.

Finally, I've spoken to 2 of the 3 operators informally but I'll start more formal discussions as soon as the business registration is completed. I've also spoken with operators outside France who would be interested in offering services as a test of borderless broadband provision.