Fiber-Optic Communication Lines (FOCL)
Working documentation: from 22 days
Price from 50000 roubles
We design fiber-optic communication lines with guaranteed high throughput, low latency and stable operation even over long distances - from cable routing to selection of equipment and connection diagrams.
We design fiber-optic communication lines for industrial, commercial and infrastructure facilities. We develop routes, select optical cables and equipment, and also create connection and redundancy schemes. A well-designed communication line ensures high data transfer speeds, minimal delays and reliable network operation under any operating conditions.
Why does the reliability of the entire facility network depend on the quality of the FOCL project?
A fiber-optic communication line is the physical basis of the communication infrastructure: it carries not only the Internet and corporate data, but also security system signals, industrial automated process control protocols, video streams and redundant technological channels. An incorrectly selected type of fiber, underestimated optical losses along the path, ignoring the attenuation margin or lack of a redundancy scheme - and the facility does not just have fast Internet, but does not have a workable dispatching, accounting or security system. All this manifests itself after installation, when the rework costs many times more than the initially competent project.
AYU-Project develops design documentation and working documentation for fiber-optic communication lines for industrial, commercial and infrastructure facilities of any complexity: from on-site fiber optic communication lines of a campus or residential complex to long inter-facility highways and access lines to electric power facilities. Our portfolio includes completed projects for Russian Railways, PJSC Rosseti Siberia, Federal Grid Company and NTEK, where the requirements for documentation and network reliability are traditionally higher than the market average.
What is FOCL and how is it superior to copper cable?
A fiber optic communication line (FOCL) is a data transmission system over an optical fiber, where the information carrier is a light pulse rather than an electric current. The physical nature of the transfer provides key technical advantages that are especially significant for B2B facilities:
- Bandwidth orders of magnitude exceeds the capabilities of copper cable and is practically unlimited when using modern CWDM/DWDM multiplexers - one fiber pair is capable of carrying several terabits per second;
- Range without signal regeneration: single-mode OS2 fiber (ITU-T G.652.D) provides transmission without amplification over a distance of more than 80 km; copper cable category 6A - no more than 100 m;
- Electromagnetic neutrality: optical fiber is not subject to electromagnetic interference from power cables, HF interference, lightning impulses and does not require grounding - critical at industrial facilities with powerful electrical equipment;
- Information security: intercepting a signal in an optical fiber without physically damaging the cable is almost impossible - unlike copper lines;
- Resource: a properly installed fiber-optic line retains its parameters for 25-40 years; Copper cable degrades much faster under high loads.
For which facilities is fibre-optic communication line design relevant?
FOCL is in demand wherever a facility requires a high-speed and reliable data transmission channel - especially when the distance between points exceeds the limitations of copper infrastructure, or with increased requirements for electromagnetic compatibility.
Main B2B construction segments:
- Residential complexes - backbone FOCL between buildings, connecting the technical floor and key rooms to the facility’s unified network, entering the building from telecom operators; FOCL provides connection of ACS, EVAC, video surveillance and intercom systems to a single infrastructure;
- Commercial and office real estate - backbone level SCS, interfloor risers and connection to operators at speeds from 1 Gbit/s and higher, redundancy of channels in the ring;
- Industrial enterprises - FOCL between production buildings, interbuildings of the workshop campus, connecting the server room to remote DATD and PLC ASU transformer substation; dielectric fiber cables are the only option for laying near high-voltage buses and in areas with explosive atmospheres;
- Electric power facilities - substations, distribution points, dispatch facilities; FOCL provides channels for RPA, telemechanics and corporate communications without the influence of high-voltage fields;
- Transport infrastructure - Russian Railways, road facilities, airports; FOCL is laid along tracks, roads and runways;
- Campus facilities - educational institutions, medical complexes, logistics parks - several buildings united into a single high-speed network via underground or overhead optical highways.
What methods of laying FOCL are we designing?
The laying method is a key design decision, which determines the type of cable, route, volume of construction work and the final cost of the line. We design fiber-optic lines using all the main installation methods:
Underground installation in cable ducts - the most secure and technologically preferable method for urban and industrial development. The optical cable is pulled into HDPE pipes Ø40-110 mm, laid in a trench or laid using the trenchless method (HDD - horizontal directional drilling). HDD is especially in demand when crossing roads, communications and hard surfaces without opening the surface. The project provides for the placement of cable wells (KK-1, KK-2) with a standardized spacing, a reserve diagram and coupling locations.
Underground installation directly into the ground - for suburban areas and routes with low intensity of subsequent excavation work. Laying depth is not less than 0,8 m (in arable lands - not less than 1,2 m). An armored cable with metal or synthetic armor is used; the project includes a route, cable wells at the joints and warning tape.
Suspended gasket on supports - self-supporting dielectric cable (OKSN, OKLK) on its own supports or on the supports of overhead power lines (FOCL-OHL). For power transmission line 110 kV and above, a cable built into the ground wire (OPGW) or wound over the ground wire is used. The project calculates the sag, wind and ice loads, support spacing, and anchorages.
Inside plant - in buildings and structures via cable trays, in boxes, in pipes, in cable shafts. The route from the input points to the optical distribution cabinets (ORSh) on the floors and in the server rooms is being designed.
Subsea gasket - when crossing water bodies; special armored cable for underwater installation, taking into account hydrological conditions.
What is included in the engineering calculation of the FOCL project?
The calculation part of the FOCL project is not background calculations, but the basis for making all key design decisions. Without correct calculations, it is impossible to justify the choice of fiber and cable type, nor to guarantee the operability of the network.
Calculation of the optical line budget - determines the maximum permissible total losses in the path (fiber attenuation, losses in connections and connectors, margin for fiber degradation, margin for build-up) and compares them with the characteristics of active equipment (transmitter power, receiver sensitivity). The result is a conclusion about the operability of the line and the power reserve. If the optical budget is negative, the line will not work even with perfect installation.
Variance calculation - for high-speed lines (10 Gbit/s and higher), not only the amplitude, but also the dispersion component of signal degradation is critical; calculated separately for single-mode and multimode fibers.
Calculation of the lengths of regeneration sections - for long trunk lines with EDFA amplifiers or regenerators.
Calculation of mechanical loads - for suspended installation: wind and ice loads on the cable and supports, sag at different temperatures, permissible support spacing.
What is included in the design documentation and working documentation on fiber-optic lines?
Documentation for FOCL is being developed in accordance with the requirements Government Decree of the Russian Federation No. 87 dated 16.02.2008 No. 87 (as amended on 21.10.2025) “On the composition of sections of project documentation and requirements for their content”, VSN 116-93 “Instructions for the design of line-cable communication structures” and SP 134.13330.2022.
Design documentation stage includes:
- an explanatory note with the choice and justification of the route, type of fiber, laying method;
- schematic diagram of a communication line with input and switching nodes;
- optical budget calculation;
- description of cable protection measures in difficult sections of the route;
- coordination of the route with the owners of the intersecting communications.
Working Documentation Stage (WD) contains:
- route plan with location reference and coordinates;
- route profile;
- layout of cable wells, couplings and cable reserves;
- cable magazine with cable brands, number of cables, cross-sections of load-bearing elements;
- wiring diagrams of ORSh and cross connections;
- circuit diagram for switching on active equipment;
- specifications of equipment and materials;
- work sheet;
- program and methodology for acceptance measurements.
Regulatory design basis FOCL
Design is carried out in accordance with the following key regulatory documents:
- VSN 116-93 “Instructions for the design of linear cable communication structures” is a fundamental industry document for the design of cable lines, including optical ones;
- WD 45.047-99 “Fiber-optic transmission lines on the backbone and intra-zonal primary networks of the VSS of Russia. Technical operation" - standards for calculating the lengths of regeneration sections and parameters of the fiber optic line;
- WD 45.156-2000 - composition of the as-built documentation for completed construction of linear fiber-optic communication lines;
- SP 134.13330.2022 “Telecommunication systems for buildings and structures” - in terms of intra-facility installation HVAC;
- GOST P ISO/IEC 11801-4 - fiber optic infrastructure for data center premises;
- ITU-T G.652, G.657 - characteristics of single-mode optical fibers;
- ITU-T G.651.1 - multimode fibers 50/125 μm OM3-OM5;
- Government Decree of the Russian Federation No. 87 dated 16.02.2008 No. 87 (as amended on 21.10.2025) “On the composition of sections of project documentation and requirements for their content” - regarding the composition of DD.
How to choose the type of optical fiber and cable?
The type of fiber is determined by distance, transmission speed and the nature of the operating environment - this is not a matter of preference, but an engineering calculation with a clear result.
| Parameter | Singlemode (OS1/OS2) | Multimode OM3/OM4/OM5 |
|---|---|---|
| Distance | To 80 km or more | Up to 300-550 m (10 Gbps) |
| Speed | 1 Gbit/s - 100 Gbit/s and higher | 10-100 Gbit/s within the facility |
| Cost HVAC | Below | Higher |
| Cost of active equipment | Higher (laser transceivers) | Below (VCSEL sources) |
| Application | Highways, interbuildings, FOCL power transmission line | Inside data center, building campuses |
For most external inter-facility FOCL, a standard single-mode cable is optimal G.652.D: balanced attenuation, compatibility with the entire fleet of active equipment, virtually unlimited throughput for future replacement of the active part. Multimode OM3 to OM5 cable is economical for short, high-speed links within a campus or data center.
Cost and procedure for ordering the project FOCL
The cost of developing design documentation and working documentation is determined by the length and method of laying the route, the number of fibers in the cable, the number of switching nodes, the composition of active equipment and the list of stages being developed. Approximate calculation - through the online calculator on the website. An accurate commercial proposal is generated free of charge after receiving the technical specifications.
To get started, leave a request: indicate the type of facility, the length of the route (approximately), the laying method and the availability of initial data - general plan, topographic survey, data on intersecting communications. The initial consultation is free, and we work remotely across Russia.
How to order the design of FOCL: stages of work
-
Submit an enquiry - the consultation is free
Form on the website or phone: +7 (383) 375-73-77 / +7 (923) 743-73-77. Indicate the type of object, the approximate length of the route and the available source data. -
Receive a Commercial Proposal Within 1 Business Day
CP with the scope of work, cost and deadlines. When ordering FOCL together with SCS, LAN or other sections of communication networks, there is a discount. -
Approve the ToR and sign the contract
We specify the stage of documentation (DD, WD or technical working design), installation method (underground sewerage, HDD, suspended, in-house), number of fibers, redundancy requirements and timing. The contract fixes the composition and cost. -
Analysis of initial data and departure to the track (if necessary)
We study the general plan, topographic survey, data on intersecting communications. If necessary, visit the site to inspect the existing cable infrastructure and clarify installation conditions. -
Routing, fiber selection and optical budget calculation
We develop the optimal route for the route. We determine the type of fiber (OS2 - for external routes; OM4/OM5 - for intra-facility high-speed lines and data center). We calculate the optical budget, dispersion (for lines 10 Gbit/s and higher) and mechanical loads (for overhead installation). -
Development of DD and coordination of the route with departments
Set DD according to Government Decree of the Russian Federation No. 87 (edited by 21.10.2025) and VSN 116-93: explanatory note, circuit diagram, calculation of the optical budget. At the same time, we coordinate the route with the owners of the intersecting communications. We eliminate the expert's comments free of charge. -
Preparation of Working Documentation (WD) and Delivery to the Client
Complete installation kit: route plan with coordinates, route profile, diagram of cable manholes and couplings, cable log with marks HVAC, installation diagrams ORSh, specifications with articles, program of acceptance measurements (attenuation, OTDR). PDF and DWG formats.
Advantages of Fiber-Optic Lines
- Fiber-optic communication lines provide reliable connectivity because optical cables can transmit signals over long distances without loss.
- The connection speed is extremely high, making fiber-optic lines ideal for handling large volumes of data.
- Fiber-optic communication is significantly more secure and reliable than radio-frequency systems and offers excellent immunity to interference.
- Fiber-optic lines have minimal installation, maintenance and operating costs.
- A high level of information security ensures that transmitted data is protected against unauthorized access.
- The systems have a service life of more than 25 years.
To learn more about our design delivery process, discuss pricing or request a consultation, contact one of our specialists.
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Frequently Asked Questions
For intra-site lines of a campus or residential complex - from 2 to 4 weeks for the design documentation stage, 3-5 weeks for detailed design documentation. For long outdoor routes with coordination of intersections and passage through the lands of different rights holders - individually, usually 4-8 weeks. The terms are fixed in the contract.
Fiber-optic cable, when installed correctly and in compliance with permissible loads, retains the standardized parameters for 25-40 years. Active equipment - transceivers, switches, multiplexers - has a significantly shorter lifespan, usually 10-15 years, and must be replaced regardless of the state of the cable infrastructure. This is one of the key advantages of fiber-optic lines over copper infrastructure: replacing the active part does not require reworking the cable routes.
Yes. Experience working with Russian Railways, PJSC Rosseti Siberia and FSK includes FOCL-VL projects: cable in lightning wire (OPGW) or self-supporting OVK (OKSN) on supports of high-voltage lines 110 kV and above, as well as on-site FOCL of substations and distribution points. These facilities require the use of dielectric cables and special technical solutions for protection from electromagnetic influences of high-voltage fields.
Technically possible, but professionally unacceptable: excess cable creates additional loops on which attenuation increases, and a spontaneously wound cable is a potential site of mechanical damage. A competent project provides for a regulated reserve at strictly defined points: at cable wells, couplings and bushings - according to VSN 116-93.
Yes. The route of an external fiber-optic communication line crossing roads, utilities, protected areas or passing through the lands of various rights holders requires coordination with the relevant departments and organizations. AYU-Project carries out this approval as part of the development of the DD and accompanies the procedure until the receipt of permits.
Calculation of the optical budget determines the total allowable losses in the path - fiber attenuation, losses on welded joints and connectors, margin for fiber degradation and possible build-up - and compares them with the characteristics of the active equipment (transmitter power, receiver sensitivity). If the optical budget is negative, the line will not work even with ideal installation. The calculation is an obligatory part of the design proposal for fiber-optic lines and the rationale for all key design decisions: type of fiber, laying method, permissible route length, number of splice points.
The answer is determined by distance and transmission speed - this is an engineering calculation, not a matter of preference. Single-mode fiber OS2 (ITU-T G.652.D) is optimal for any external routes longer than 100-150 m: the cable is cheaper, the throughput for future replacement of the active part is practically unlimited. Multimode OM4/OM5 is economically justified for short, high-speed lines inside a building or data center, where active equipment with VCSEL sources is much cheaper than single-mode laser transceivers. The optimal type is determined by calculating the optical budget in each specific project.
Yes. If the design documentation has already passed the expert review, we develop only working documentation based on it. To do this, we need an approved PD kit with circuit diagrams, optical budget calculations and an agreed route. Cost and terms are calculated individually.
State expert review is mandatory for publicly funded capital construction projects and for projects falling within the requirements of the Russian Urban Planning Code. For commercial and industrial facilities that do not require a building permit, a combined design and detailed-design package may be sufficient without expert review. AYU-Project supports the documentation through state or independent expert review and resolves reviewers' comments at no additional charge.
To get started, all you need is: a general plan of the facility or a topographical survey of the route; approximate route length and preferred laying method; data on crossed communications (if available); technical specifications or requirements for throughput and redundancy. We help collect the missing initial data - including requesting technical specifications from telecom operators and owners of related communications.
Yes, even for an inside plant installation, working documentation is necessary: without it, the installation organization cannot accurately calculate cable lengths, determine the installation locations of ORSh, reserves and couplings, and also confirm the operability of the route by calculating the optical budget. For capital construction projects, the on-site fiber-optic communication line (FOCL) is included in the “Communication Networks” section of the design documentation, developed according to Russian Government Resolution No. 87 (ed. from 21.10.2025) and SP 134.13330.2022.
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