Fiber Optic Cables

How to choose fiber components

Four decisions settle almost every fiber specification on an Iraqi project:

• Single mode or multimode. Single mode (OS2, 9/125 um core) is correct for anything that leaves the building: campus backbone, inter-building runs, GPON and FTTH aggregation, and metro transport. Multimode (OM1 at 62.5/125 um, OM2, OM3 and OM4 at 50/125 um) is for short high-bandwidth runs inside a server room or a data centre row.
• Connector family. LC is the dominant interface on modern SFP, SFP+ and QSFP optics and gives roughly twice the panel density of SC. SC remains the standard on ODF ports, FTTH boxes and older transport equipment. ST appears on legacy plant that still has to be reached.
• Polish. UPC is the general-purpose polish. APC uses an 8 degree angled endface that deflects reflected light out of the core, which is why PON and FTTH deployments specify it.
• Where it terminates. Rack builds land in a 19 inch ODF. Cabinets, street furniture and small nodes land on a DIN rail ODF. Subscriber drops land in a wall or pole mounted FTTH box.

What each sub-category covers

Where these parts get used in Iraq

• ISP last-mile build-out. Feeder fiber into a street cabinet ODF, distribution into FTTH boxes on the building, drops terminated with OS2 APC pigtails.
• Government and bank server rooms. OS2 uplinks between buildings, OM3 or OM4 inside the room, everything landing on a 19 inch ODF above the switch stack.
• University campuses in Erbil and Sulaymaniyah. Single mode between blocks, multimode inside each block, patch cords sized per rack row.
• New-build offices and towers. Riser fiber terminated floor by floor, with an FTTH box or a DIN rail ODF in each floor cabinet.

Related reading: Fiber Optic Patch Cord Types Explained: OM1 to OS2, LC to SC, UPC vs APC and How to Plan a Structured Cabling Installation. For copper horizontal cabling in the same build, see Copper Cables, and for the enclosures that hold it all, see Racks.

To specify a bill of materials, confirm availability, or request a project quotation anywhere in Iraq or the Kurdistan Region, contact a DAD LINK authorized distributor.