1 Welcome John Mellis BT Laboratories Blown Fibre as a Reduced Cost Network Planning Solution
2 Scope Planning Rules Costing Assumptions Conventional Cable Solution Blown Fibre Solution Cost Comparison Conclusions
3 Planning Rules Maximum distance between flexibility points is 0.7 km Maximum continuous tube length is 1 km Maximum fibre unit blowing distance is 1.4 km in either direction from a central blowing point Penetration = 30% of potential customers in 10 years Duct dimensioned for at least 10 years demand Cable / BF tube dimensioned for at least 3 years demand BF unit installed when required for customer connect.
4 Costing Scenario Based on Second Operator Access Network Low Penetration Slow Roll out
5 Costing Assumptions 2 fibres from Point of Presence (POP) to each customer Same hand hole positions used for BF and conventional cable All fibres of a conventional cable spliced at each OTIAN node (fibre pair accessible at any node without risk to working fibres) Network planning, record keeping and project management included Net Present Value (NPV) rate is 10% above inflation.
6 Conventional Cable Solution (After Year 0) PoP Distance from POP (m) spine + 1 spare Duct connector 50m O T I A N 6 distribution Hand Hole OTIAN Node Customer Ten 32mm OD ducts and one 16 fibre cable Ten 32mm OD ducts and one 8 fibre cable Two 32mm OD ducts and one 4 fibre cable
7 Conventional Cable Solution (After Year 9) PoP All drops are 100m Distance from POP (m) Hand Hole OTIAN Node Customer Ten 32mm OD ducts and three 16 fibre cables Ten 32mm OD ducts and one 16 fibre cable Ten 32mm OD ducts and two 8 fibre cables Ten 32mm OD ducts and one 8 fibre cable Two 32mm OD ducts and one 4 fibre cable
8 Blown Fibre Solution (After Year 0) PoP Distance from POP (m) Hand Hole OTIAN Node BF Tube Flexibility Point Customer Four 32mm OD ducts and one 7 tube BF assembly One 32mm OD duct and one 2 tube BF assembly
9 Blown Fibre Solution (After Year 9) PoP All drops are 100m Distance from POP (m) Hand Hole OTIAN Node BF Tube Flexibility Point Customer Four 32mm OD ducts and two 7 tube BF assemblies Four 32mm OD ducts and one 7 tube BF assembly One 32mm OD duct and one 2 tube BF assembly
10 Blown Fibre Tube Configuration 2 spine + 1 spare 1 distribution 4 Ducts distribution duct Customer BF Tube Flexibility Point 7 tube BF 2 tube BF Hand hole containing OTIAN node or BF tube flexibility point BF Tube Flexibility Point Empty duct at this point can be used to feed customers from Hand hole 3
11 Blown Fibre Unit Configuration 8 customers fed using only 6 tubes from the POP. Use highest fibre count BF for node feeds to minimise tubes. POP Distance from POP (m) 2 fibre unit 4 fibre unit Tube flexibility point OTIAN node Customer
12 How Can BF Offer Cost Savings ? Reduced up front investment - lower Net Present Value Cost Eliminate unused fibre due to fibre being dropped off mid way Reduction in ducts required for same customer capacity Minimise splicing by feeding direct from POP / Track Joint to customer Replace some splicing nodes with cheaper tube joints.
13 Cost Comparison
14 Conclusions BF offers savings of up to 26% over conventional cable for a low penetration tree and branch network (assuming duct minimisation for BF) Without duct minimisation BF offers only 6% saving No cost advantage indicated for BF drops only.
15 Thank You John Mellis BT Laboratories Tel :