Structured Cabling: The Physical Foundation of Your Business Network

Structured cabling is the organised system of cables, outlets, patch panels and rack cabinets that delivers network connectivity to every point in a building, designed to the ISO/IEC 11801 and EN 50173 standards. Properly installed, it lasts 15–20 years, carries data, VoIP telephony, Wi-Fi and CCTV, and must always be instrument-certified on completion.

It looks like the least interesting part of your IT infrastructure — which is precisely why it's where the worst savings are made. In more than 25 years of working with SMEs across the Milan area, we've seen slow networks, crackling phone lines and access points that reboot themselves at random. In a surprising number of cases the culprit wasn't the server or the firewall, but a badly crimped cable behind someone's desk.

What structured cabling is (and how it differs from "just running cables")

Cabling is structured when it follows a standard, hierarchical design that is independent of whatever equipment gets plugged into it. In practice: every workstation has its own outlets, every outlet terminates at a numbered patch panel in the cabinet, and every link is documented and tested. Swap your phone system, switches or ERP tomorrow and you won't touch a single metre of cable.

The opposite is cabling that "grew organically": trailing extension leads, desktop switches daisy-chained under desks, unlabelled cables vanishing into the suspended ceiling. It works — until it doesn't. At that point, every fault diagnosis becomes an archaeological dig, paid for in hours of downtime.

The standard elements of a structured installation are:

• Horizontal cabling: the copper runs connecting user outlets to the floor's comms room. The permanent link must not exceed 90 metres (100 metres including patch leads).
• Backbone: the link between floors or buildings — almost always optical fibre these days.
• Rack cabinet and patch panels: the concentration point where every outlet terminates in an orderly fashion, and where switches, firewalls and servers live.
• User outlets (TOs) and patch leads: the network access point for PCs, phones, printers and access points.
• Labelling and documentation: every point carries a unique identifier, recorded on the outlet, the patch panel and the floor plan.

Cable categories: what to specify in 2026

The "category" defines the guaranteed performance of a copper cable. It's the first line to check on any quotation, because the cable itself is a small share of the total cost — yet it locks in your network's capability for the next 15 years.

Cat 5e: legacy only

Guaranteed for 1 Gbps up to 100 metres. A Cat 5e installation in good condition doesn't need ripping out on principle, but installing new Cat 5e today makes no sense: the saving over Cat 6A is marginal and the useful life far shorter.

Cat 6: the bare minimum

Handles 1 Gbps at 100 metres, and 10 Gbps only over short runs (around 55 metres, under favourable conditions). Acceptable for small offices with stable requirements, but it's a choice that looks backwards.

Cat 6A: the standard we recommend

Cat 6A guarantees 10 Gbps over 100 metres and is today's benchmark for new business installations. There's a second, less well-known reason to choose it: PoE. Wi-Fi 6/7 access points, IP cameras and desk phones are increasingly powered over the network cable itself (up to 90 W under the 802.3bt standard), and the thicker conductors in Cat 6A dissipate heat far better inside cable bundles. If you're evaluating a cloud-hosted VoIP phone system, the cabling is the first thing to check.

Cat 7 and Cat 8: niche cases

Cat 7 uses proprietary connectors with limited adoption, and in real-world SME practice it's rarely justified. Cat 8 reaches 25/40 Gbps but only over 30 metres: it's designed for links inside the data centre, not for floor cabling.

Optical fibre: the backbone

Between floors, warehouses or buildings, fibre is the right answer: OM4 multimode for short on-site runs, OS2 single-mode where distances grow or you want maximum future headroom. Fibre is also immune to electromagnetic interference — a tangible advantage in production halls full of motors and inverter drives.

Standards and the CPR: what a compliant installation must meet

A properly engineered structured cabling installation references three families of standards:

• ISO/IEC 11801 and EN 50173: these define the architecture, performance and distances of generic cabling for offices, industrial premises and data centres.
• TIA/EIA-568: the American standard, useful above all for termination schemes (the widely used T568B).
• The Construction Products Regulation, CPR (EU 305/2011): since 2017, cables permanently installed in buildings are classed as construction products and must carry a declared fire reaction class. For office buildings in Italy, standard practice under the CEI guidelines typically calls for cables rated Cca-s1b,d1,a1: in a fire they burn more slowly and release fewer toxic fumes.

This is a point worth being pedantic about with any supplier: an aggressive quote based on Eca-class cable isn't a saving — it's a non-compliant installation.

Certification: without instrument testing, you've bought nothing

This is what separates a professional installer from a well-meaning electrician. On completion, every single link must be measured with a network certifier (a Fluke DSX or equivalent) that verifies attenuation, NEXT, return loss and length against the limits of the declared category.

The result is a report for every outlet, with a PASS or FAIL verdict. You need it for three practical reasons:

1. Contractual proof: you paid for a Cat 6A installation, and you hold the measurements that prove it.
2. Extended warranty: certified systems from the major manufacturers carry channel warranties of up to 25 years — but only with a qualified installer and the certification reports.
3. Future diagnostics: when a workstation starts misbehaving three years from now, you'll know within minutes whether the problem is physical or application-level.

If you inherit an installation with no documentation, a re-certification and re-labelling campaign costs little compared with what it saves in support time. It's one of the first steps we propose in our business network support projects.

The mistakes we see most often in SME installations

• Data and mains cables sharing the same trunking with no separation: interference, CRC errors and unpredictable performance.
• Daisy-chained switches under desks instead of additional outlets: every unmanaged switch is a blind spot and a failure waiting to happen.
• A rack cabinet with no ventilation and no order: bird's-nest patching turns every intervention into a gamble and pushes up equipment temperatures.
• No labels: the network map exists only in the head of whoever installed it — who usually left the company years ago.
• Zero spare points: cabling one extra workstation during the fit-out costs pennies; doing it afterwards costs a dedicated call-out.
• Copper backbone between buildings: beyond the distance limits, it exposes your equipment to surges and earth potential differences. Between buildings, it's fibre — always.

When it's worth replacing (or extending) your cabling

The typical warning signs: slow file transfers to the company NAS despite gigabit switches, degraded VoIP calls, upgraded Wi-Fi that doesn't improve because the access points are throttled by the cable feeding them, and recurring tickets from specific desks. An office move, a refurbishment or a large rollout of IP cameras and PoE access points is also the right moment to bring the installation up to Cat 6A.

Remember that cabling is a physical security matter too: live unused outlets and rack cabinets anyone can open are entry points into your network, every bit as much as the logical ones you close with your business firewall.

What structured cabling costs

The numbers vary with the building (suspended ceilings, existing trunking, structural constraints), but as a rule of thumb: a certified Cat 6A network point, in an office that can be cabled without building work, comes in at roughly €80–150 per outlet, covering materials, installation, termination and certification. Fibre backbones, cabinets and active equipment are a separate line and need sizing against the specific project.

The right way to read those figures is over a 15–20 year service life: across that horizon, the difference between a cheap installation and a compliant, certified one works out at a few tens of euros per workstation per year — less than the cost of a single afternoon with the network down.

How we work at TN Solutions

For over 25 years we've been designing and maintaining business networks from Melzo, just outside Milan, with ISO 9001 and ISO 27001 certified processes. A structured cabling project with us always follows the same path: site survey, design with floor plans and bill of quantities, CPR-compliant installation, instrument certification of every link, and handover of the complete documentation. And we don't disappear afterwards: we look after the network over time, from the switches to the Wi-Fi, under our support contracts.

Let's talk about your network

If the network is slow, opening the rack cabinet fills you with dread, or you're planning a move or an expansion, the right time to sort out your structured cabling is before it becomes an emergency. Tell us where you stand: a site survey and assessment are our starting point, not a commitment.

Call us on 02 9517550 or reach us through the contact page: a TN Solutions engineer — not a salesperson — will call you back to understand what you actually need.