FTTC, FTTP and the Last Mile: Broadband Access Technologies Compared

Fibre to the X describes how far fibre runs before copper or coaxial cable takes over for the final stretch. The naming is consistent once you know it, and the differences matter because the copper section determines the speed.

The variants

FTTP or FTTH — fibre to the premises or home. Fibre all the way to the building, with no copper in the access path. The highest performance and the most expensive to deploy, because every property needs a physical fibre installation.

FTTB — fibre to the building. Fibre to a multi-occupancy building, with existing internal copper distributing to individual units. Short copper runs, so performance is close to FTTP.

FTTC — fibre to the cabinet. Fibre to a street cabinet, copper from there to the premises, typically a few hundred metres. Far cheaper than FTTP because it reuses the existing copper, and the copper section sets the ceiling.

FTTN — fibre to the node, the same idea with a longer copper run and correspondingly lower speeds.

The rule to hold: the shorter the copper, the higher the speed, because attenuation over twisted pair increases sharply with distance and with frequency. That is why two customers on the same FTTC service get different speeds depending on how far they sit from the cabinet, and why the quoted figure is "up to".

Cable and other access methods

Cable uses the coaxial television network, with fibre to a neighbourhood node and coaxial from there. Speeds are high, and the coaxial segment is shared among the premises on it, so throughput varies with neighbours' usage in a way that a dedicated copper pair does not. Upload is typically much lower than download because of how the spectrum is allocated.

Fixed wireless and satellite cover areas where cable installation is impractical. Satellite's distinguishing characteristic is latency: geostationary services add substantial delay that no bandwidth improves, which breaks interactive applications and, notably, anything sensitive to round-trip time. Low-earth-orbit constellations reduce this considerably.

Cellular is increasingly a primary connection for small sites and a standard backup path elsewhere — the out-of-band route discussed under out-of-band management.

Symmetry and contention

Two properties that matter more than headline speed for business use, and are rarely on the marketing material.

Symmetry. Consumer broadband is asymmetric — far more download than upload — because household usage is. A business hosting services, running video conferencing, or backing up offsite is constrained by upload, and an asymmetric service with an impressive download figure may be unusable for it. FTTP services frequently offer symmetric options; FTTC generally does not.

Contention. Capacity is shared upstream, so the quoted speed is a maximum rather than a guarantee. Business services specify a contention ratio or provide a committed information rate with a service level agreement, which is what you are paying the premium for — and whether that SLA is meaningful depends on reading it the way described under SLOs and SLAs.

Troubleshooting the access line

Establish which segment is the problem first. Check the modem or router's line statistics — sync speed, attenuation, signal-to-noise margin — because those describe the copper or coaxial section independently of anything on your network.

A line that syncs well below its expected rate, or shows a low noise margin, points at the physical path: distance, damaged cable, water in a joint, or interference. A line that syncs correctly but performs badly points at contention, at the provider's network, or at something on your side.

Interference and degradation appear as errors, and the interface counters tell you where — the diagnostic sequence under CRC and frame check sequence errors.

For resilience, a second connection is only redundant if it is genuinely independent: a different medium, a different physical path into the building, and ideally a different provider — because two services resold over the same underlying infrastructure fail together, which is the dependency trap discussed under site resilience.

Exam angles

Know FTTP/FTTH as fibre to the premises, FTTB to the building, FTTC to the cabinet and FTTN to the node, in decreasing order of performance as the copper run lengthens. Know that copper distance and attenuation set the achievable speed on FTTC. Recognize cable as using a shared coaxial segment with asymmetric speeds, and satellite as latency-limited regardless of bandwidth. Distinguish symmetric from asymmetric service and understand contention ratios and committed rates.