6.14 Feeder Cables
Cables Connecting OLT at CO to Remote splitter/FDT/FDH
Laid in P2P or ring topology
Single mode, loose tube available from 12F-288F
6.15 Distribution Cables
Cables connecting FDT Splitter to FAT/Closures.
Laid in P2P/Star topology from FDT/Splitter location.
Single mode, loose tube available from 12F-96F
6.16 Drop Cables
Last mile from FAT to FTB
Last mile from FTB to FOB/ATB (customer premises)
Bending radius 15 mm.
Single mode, center or loose tube available from 2F-4F
Network Sector – Design ةكبشنا ىيًصت
Doc. Number: GL 621211–02-03 Issue #: 1 - Issue Date: 23 May, 2010
7. GPON Design Features and Characteristics (ISP & OSP) 7.1 ISP Design – Fundamental Planning Guidelines:
To develop a network capable to deliver 100 Mbps
The line plant shall be developed to meeting the ultimate requirements.
The initial capability of delivery of the network shall be 40 Mbps, with 1:2 splitters in the central office and 1:32 at the remote end.
7.2 OSP Design – Fundamental Planning Guidelines:
Scalable network
Deployment of technically matured products
Economical component prices
Reduction in CAPEX and OPEX
Ease to install, maintain and operate
Quick to restore the service
Design FO network within 28 dB loss budget, end to end
Cascaded, Centralized and pre connectorized splitters in CO & FDTs
Splitter ratio 1:2 in CO and 1:32 in FDTs
Induction of 2F drop cables in Indoor and Outdoor
LC/APC Connectivity and connectors at all stages
Use of existing cabinet and or locations as splitter cabinet in some cases
Distribution cables to be loose tube 8F/16F/24F/48F/96F, from Outdoor splitter cabinet
FAT Closures in Joint Box to lay drop cable up to fiber FTB or FOB/ONT
Provision of 2F per unit and splice through 1F drop closures (FAT)
Termination of single fibers in ONT and ODF / Splitter (FDH) Cabinet
8. Fiber Optic Civil & Cable Development (Green & Brown Field) 8.1 Brown Field Considerations:-
Fibers already laid for local networks shall be considered for utilization while developing the GPON network.
To prevent additional expenses in civil work all existing infrastructures is proposed to be used as far as possible.
Network Sector – Design ةكبشنا ىيًصت
Doc. Number: GL 621211–02-03 Issue #: 1 - Issue Date: 23 May, 2010
Where there are no duct spaces available and the distances are short, fiber cable may be shared the available duct space with the existing copper cables, if possible through a sub duct and following to be taken care as:
a) If copper cable is already exists, lay sub duct over copper cable and then pull the fiber cable in sub duct.
b) Fiber cable should not be directly pulled over copper cable or vice versa.
All the existing outdoor MSAN & copper cabinets may be considered to accommodate the splitters – No consideration has been taken for the time being.
8.2 Green Field
Considerations:- Considering the future of fiber based GPON technology and to cope up with the future
prospective services and bandwidth demand, the network development shall be planned on fiber optic cable from the OLT in central office to the ONT in the customer premises.
Fiber Optic cables, splitter cabinet & civil (ducts, joint boxes, etc) shall be proposed in
the most economical way.
The OSP fiber counts from the central office shall be of a suitable size to ensure
meeting the future capacity requirements.
Considering the initial low take rate, spare fibers, splitter usage, future service
offerings, distance from central office and other unknowns, the number of fibers in the OSP cable would more likely end up being closer to 1 Fiber per 20 to 32 tenants.
Where the diversity is required for palaces, airports, police offices, hospitals,
ministries or E-government sites etc; the fiber can be routed in two different routes, diversity routes; (Pre-approval required in such cases).
Requirements of direct fibers for business establishment are also to be considered
while sizing the main cables.
The spare fibers available in the junction cable network to be utilized to connect,
OLTs in one exchange area and ONTs in the other Exchanges.
The duct network shall be considerably reduced and the corresponding joint box /
manholes can also be reduced, as the number of FO cables that would be installed shall
be far less than the legacy copper network.
Network Sector – Design ةكبشنا ىيًصت
Doc. Number: GL 621211–02-03 Issue #: 1 - Issue Date: 23 May, 2010
Accordingly, the ducts shall be reduced to maximum 2Wx110 mm and Joint Boxes
(HH) of two cover. One cover HH may be exception if no FAT will be proposed or very low numbers connections like mosques, schools or 2/3 villas.
As for as possible the joints in the main cable may not be planned to be operated
frequently to divert or put through fibers.
The main joint closures have 4 in ports and 4 out ports which can be used for multiple
branching of distribution
The drop closures (FATs) are recommended to be installed inside joint boxes close to
group of villas. These have 24 outlets for drop cables.
Joint location for maximum utilization of full drum length to avoid short cut lengths.
8.3 A) Civil Work Design Parameters – Feeder & Distribution
Use Ne system to design all FTTH works.
PEC 110 mm Empty or PEC 110 mm with 5-sub/ducts to be used between hand holes
or manholes.
Span between hand-holes to be labeled as 110 mm/5SD-xx m.
32 mm HDPE drop duct/conduit for each residential parcel.
50 mm HDPE drop duct/conduit for business/commercial and very high forecast
parcels (need of multiple lead in duct are exception for complexes and business compounds).
Drop conduit from hand-holes to each parcel to be labeled as 50 xx m or 32
mm-xx m
Drop ducts from each hand holes to be numbered in sequence and follow the rule left
to right or anti-clock wise.
Drop ducts should be labeled and numbered as per the site.
Hand-hole covers 2 to be used to accommodate FATs and FO closures for distribution
and also for feeder routes with in distribution areas.
Small or Mini manholes or 2-cover hand holes to be used for feeder route outside
distribution area depending on the forecast and future needs in the vicinity.
2PEC/5SD (or) 4PEC/5SD to be used outside for feeder route outside distribution area
depending on the forecast and future needs in the vicinity.
Hand-hole 1-cover to be used if no possibility of FO closures and FAT now or in
future.
Network Sector – Design ةكبشنا ىيًصت
Doc. Number: GL 621211–02-03 Issue #: 1 - Issue Date: 23 May, 2010
Feeder civil with distribution to be included in distribution civil as shared conduits and
hand-holes for feeder and secondary. Hence no distinct trenches for feeder and distribution in same side/street and distinct conduits for feeder and distribution.
All parcel (existing, under construction or empty) will be provided with duct, while the
cable will be provided for existing and under construction units. No bag and buried will be used.
Single span length to be shown from hand-hole to hand-hole.
Single span length to be shown for drop ducts from hand-hole to each Parcel.
Efforts to be made to reduce the numbers of hand-holes in accordance with the FAT
capacity of 24 drops from one FAT. FAT refer to FTTH DP for SFUs/villas.
BOQ to be calculated precisely particularly the trenching and conduit lengths.