| Full title | Optical Fiber Cabling and Components Standard |
| Publisher | Telecommunications Industry Association (TIA), committee TR-42.11 |
| Current revision | ANSI/TIA-568.3-E, published 29 September 2022 |
| Status | Current. Addendum 568.3-E-1 is in ballot, with a full revision (568.3-F) planned. |
| Replaces | ANSI/TIA-568.3-D (2016) and its addendum 568.3-D-1 (2019) |
| Related standards | ANSI/TIA-598, ANSI/TIA-568.0, 568.1, 568.2, ISO/IEC 11801-1, EN 50173-1 |
What it covers
ANSI/TIA-568.3 applies to premises optical fibre cabling and components. It sets requirements for cable, connectors, connecting hardware, patch cords, array cables and transitions, and for the transmission performance and testing of installed cabling.
The main clauses are:
- optical fibre cable
- connecting hardware (connectors, adapters and splices)
- cords, array cables and transitions
- optical fibre transmission performance and test requirements
- annexes on connector performance, grandfathered fibre types, maintaining polarity (Annex C), optical branching components, and field-testing guidelines for length, loss and polarity (Annex E)
Revision history
| Document | Date | Notes |
|---|---|---|
| ANSI/TIA-568.3-D | October 2016 | Revision of the optical fibre standard |
| ANSI/TIA-568.3-D-1 | January 2019 | Added OM5 and OS1a names, lime colour for OM5 connecting hardware, and testing of MPO-terminated cabling |
| ANSI/TIA-568.3-E | September 2022 | Current revision. Includes D-1. Adds connectivity Methods U1 and U2, adds IEC and ISO/IEC fibre designations, removes OM1 and OM2 colour designations, and changes the multimode reference-grade to standard-grade allowance to 0.5 dB. |
| ANSI/TIA-568.3-E-1 | In ballot | Addendum. Includes extra array polarity variants requested for IEEE 802.3dj. |
Recognised fibre types
568.3-E uses the ISO/IEC names OM3, OM4, OM5, OS1a and OS2, alongside the IEC and TIA fibre specification names. Colour designations for OM1 and OM2 were removed in 568.3-E.
Maximum cable attenuation
| Cable type | Wavelength | Maximum attenuation |
|---|---|---|
| Multimode 50/125 µm (OM3, OM4, OM5) | 850 nm | 3.0 dB/km |
| Multimode 50/125 µm (OM3, OM4, OM5) | 1 300 nm | 1.5 dB/km |
| Single-mode, inside plant (OS1a, OS2) | 1 310 nm and 1 550 nm | 1.0 dB/km |
| Single-mode, outside plant (OS1a, OS2) | 1 310 nm and 1 550 nm | 0.5 dB/km |
OM5 is wideband multimode fibre. Field testing of OM5 is carried out at 850 nm and 1 300 nm.
Loss budget
The link attenuation allowance is the sum of the allowances for cable, connections and splices:
Link loss allowance (dB) = (cable attenuation in dB/km × length in km) + (number of mated connector pairs × 0.75 dB) + (number of splices × 0.3 dB)
| Element | Maximum allowance |
|---|---|
| Mated connector pair (standard grade) | 0.75 dB |
| Splice | 0.3 dB |
| Cable | Attenuation coefficient × length |
Worked example: a 150 m OM4 link at 850 nm with two mated pairs and no splices. Cable 3.0 × 0.15 = 0.45 dB. Connectors 2 × 0.75 = 1.50 dB. Allowance 1.95 dB.
The standard also gives tighter values for reference-grade test cords used during testing. Test equipment applies these when the reference-grade method is selected.
Polarity
Annex C sets out how to keep transmit and receive in the right place across a link.
| Cabling | Methods |
|---|---|
| Duplex connectivity | Consecutive-fibre positioning and reverse-pair positioning |
| Array (MPO) connectivity | Connectivity Methods A, B and C |
| Array cabling carrying multiple duplex signals | Methods U1 and U2 |
All components in a link, including trunks, cassettes and cords, must follow the same method.
Colour coding
568.3 refers to ANSI/TIA-598, Optical Fiber Cable Color Coding, for fibre and cable colours. 568.3-D-1 introduced lime as the colour for OM5 connecting hardware.
How it relates to other standards
- ISO/IEC 11801-1 and EN 50173-1 use the same OM and OS category names. Their attenuation figures can differ from TIA figures, so check which standard the contract names.
- ANSI/TIA-568.0 and 568.1 set the cabling topology that 568.3 components are used in.
- Application standards such as IEEE 802.3 set their own channel loss and length limits, which can be tighter than the cabling allowance.
What it means in practice
- Calculate a loss budget for every link before testing. A tester needs the length, number of connections and splices to set a pass limit.
- Test multimode at 850 nm and 1 300 nm, and single-mode at 1 310 nm and 1 550 nm.
- Check that a test report names TIA-568.3 and the reference method used.
- Confirm the polarity method on drawings and order trunks, cassettes and cords to that method.
- Check the application loss limit as well as the cabling allowance. A link can pass 568.3 and still exceed the budget for a high-speed application.
Related reading: Fibre optic loss budget: how to calculate insertion loss · Single-mode vs multimode fibre: OM3, OM4 and OS2 explained.