Question 1

How does cable broadband work, and what is DOCSIS?

Accepted Answer

Cable broadband delivers internet over the **coaxial television network**, using a standard called **DOCSIS** — Data Over Cable Service Interface Specification — that defines how data shares that cable with everything else on it.

**The physical arrangement.** Modern cable networks are **hybrid fibre-coaxial (HFC)**: fibre runs from the head-end to a local **node** serving a neighbourhood, and coaxial cable covers the final stretch to homes. So it is partly fibre, though not to the premises.

**How data shares the cable.** The coaxial cable carries a wide range of radio frequencies. Specific **channels** are allocated to downstream and upstream data, and **channel bonding** combines many channels to increase throughput — which is what successive DOCSIS versions have largely done more of.

**Why upload is so much lower.** This is the defining characteristic. The frequency spectrum was originally designed for **television**, which is overwhelmingly one-directional. Only a narrow band at the low end of the spectrum was left available for the return path, and it is both small and the noisiest part of the cable. The result is a sharply asymmetric service — high download, comparatively meagre upload — and it is an architectural inheritance rather than a commercial choice.

**Why performance varies by time of day.** Everyone on a node **shares** the same channels. When neighbours are streaming in the evening, the shared capacity is divided. **Node splitting** — subdividing a node to serve fewer homes — is the operator's main remedy.

**The DOCSIS versions:**

**3.0** introduced channel bonding, enabling the first genuinely fast cable services.

**3.1** added far more efficient modulation and much higher capacity, and is the basis of gigabit cable.

**4.0** substantially increases upstream capacity, addressing the asymmetry directly by reallocating spectrum — which is the significant development for cable's competitiveness against full fibre.

**Practical points:** the **modem must support** the version your provider uses; **signal levels and noise** on the coaxial run cause many faults, and **ingress noise** from a damaged cable or connector anywhere on the shared segment can degrade service for a whole street; and splitters and old internal wiring are a common cause of problems.

Question 2

What is fixed wireless access, and is it as good as a cable?

Accepted Answer

Fixed wireless access (FWA) delivers broadband to a building over a radio link rather than a wire — typically from a mobile network's 4G or 5G masts to a receiver in your home. Why it exists. Digging

Question 3

How does fibre actually carry data?

Accepted Answer

As pulses of light down a strand of extremely pure glass, guided by a physical effect that keeps the light from escaping even as the cable bends. The physical mechanism. A fibre has a core of glass

Question 4

What is the difference between FTTC and FTTP?

Accepted Answer

How far the fibre actually goes — and that single fact determines almost everything about the speed and reliability you get. FTTC — fibre to the cabinet. Fibre runs from the exchange to the green

Question 5

How does the internet actually cross oceans?

Accepted Answer

Through submarine fibre optic cables lying on the seabed — not satellites, which carry a negligible share of intercontinental traffic despite what most people assume. The scale. Well over 95% of

Question 6

What is radio spectrum, and why is it auctioned?

Accepted Answer

Spectrum is the range of radio frequencies usable for wireless communication — and it is auctioned because it is a genuinely finite shared resource where two users of the same frequency in the same

Question 7

What do "up to" and "average" broadband speeds actually mean?

Accepted Answer

They are defined advertising terms rather than promises, and understanding which one you were given tells you what you can actually hold a provider to. "Up to" speeds described the theoretical

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