What the Acronyms Actually Mean
The FTTx family of acronyms all share the same structure: "Fiber to the X," where X describes the termination point of the fiber run. FTTH is Fiber to the Home — the fiber ends at your house. FTTC is Fiber to the Cabinet — the fiber ends at a street-side distribution cabinet. FTTP is Fiber to the Premises — a term used primarily in the UK that encompasses any deployment where fiber reaches the customer's building, making it functionally synonymous with FTTH for residential connections.
The critical distinction is what happens after the fiber ends. In FTTH and FTTP, nothing happens — the fiber is the entire connection. In FTTC, a copper telephone wire carries the signal from the street cabinet to your home using VDSL2 or G.fast technology. That copper segment is called the last mile, and it is what limits FTTC performance relative to full fiber.
FTTH: Full Fiber All the Way
In an FTTH deployment, a single-mode fiber strand runs from the ISP's OLT (Optical Line Terminal) — through passive optical splitters in the distribution network — all the way to an ONT (Optical Network Terminal) installed at your home. Every meter of the path between the ISP and your premises is glass fiber. There is no copper anywhere in the last-mile connection.
This pure-fiber path delivers the full performance benefits the technology is capable of: symmetric speeds from 300 Mbps to 10 Gbps, round-trip latency of 1–5 ms, and signal quality that does not degrade with distance from the cabinet. A home 50 meters from the distribution point and a home 2 km away receive identical signal quality, because attenuation in single-mode fiber over these distances is negligible. FTTH is the deployment model used by AT&T Fiber, Google Fiber, Verizon Fios, and most modern fiber ISPs in the United States.
FTTC: Fiber to the Cabinet, Then Copper
FTTC is a hybrid approach that upgrades the backbone without replacing the expensive last-mile copper infrastructure. Fiber runs from the central office to a street cabinet — a green metal box on the pavement that contains active electronics including a DSLAM (Digital Subscriber Line Access Multiplexer). From the cabinet, existing copper telephone wire carries the signal to homes using VDSL2, which achieves speeds of up to 80 Mbps downstream and 20 Mbps upstream under ideal conditions.
The speed you actually receive from FTTC depends heavily on your distance from the cabinet. At 50–100 meters, VDSL2 can achieve close to its theoretical maximum. By 300 meters, speeds drop noticeably. Beyond 500 meters, you may receive less than half the rated speed. Because cabinets serve the surrounding neighborhood, and houses are at varying distances, FTTC produces a wide range of actual customer speeds from a single service tier. This variability is one of FTTC's main criticisms.
FTTP: The UK Term for Full Fiber
In the United Kingdom, Openreach — the infrastructure arm of BT that owns most of the nation's telephone network — uses the term FTTP (Fiber to the Premises) for its full fiber product. This is the same technology as FTTH: fiber all the way to the building with an ONT at the customer end. Openreach's FTTP rollout, which accelerated significantly after 2020, aims to pass the majority of UK premises by the late 2020s.
The distinction between FTTP and FTTH is largely geographical and organizational. Some engineers use FTTP as the broader term covering both residential (FTTH) and business premises (FTTB — Fiber to the Building), while others use them interchangeably for home connections. From a customer's perspective, if your ISP describes your connection as FTTP or FTTH, you have full fiber and can expect the same performance characteristics.
FTTB: Fiber to the Building
FTTB (Fiber to the Building or Fiber to the Basement) is common in multi-dwelling units like apartment blocks and office buildings. Fiber runs to a network termination point in the building's basement or communications room, and then copper or short Ethernet runs distribute the connection to individual units. Because the copper segment is very short — typically under 100 meters within a single building — FTTB can deliver speeds approaching FTTH in practice. The key difference is that the infrastructure within the building is shared and often managed by the building owner rather than the ISP, which can create bottlenecks if the in-building wiring is old or poorly maintained.
How to Find Out Which Type You Have
The most reliable indicator is your home equipment. If you have a box labeled ONT (Optical Network Terminal) with a fiber cable entering it and an Ethernet cable going to your router, you have FTTH or FTTP. If you have a DSL modem connected to a standard telephone socket via a gray or white telephone cable, you are on FTTC or ADSL with a copper last mile.
You can also contact your ISP directly and ask whether your address has full fiber or FTTC. In the US, the FCC's National Broadband Map identifies the technology type at each address. In the UK, Openreach's checker at checker.ofcom.org.uk shows the technology available at your postcode. If your ISP advertises speeds as "up to 80 Mbps" with highly variable estimates by address, you are almost certainly on FTTC.
Why the Last Mile Determines Your Speed Ceiling
It is a common misconception that the fiber backbone is what limits broadband speeds. In reality, backbone fiber between cities and between ISPs carries terabits per second of aggregate traffic — it is almost never the bottleneck. The speed limit for residential connections is almost always in the last mile: the segment between the ISP's local distribution equipment and your home.
For FTTH, the last-mile medium is glass fiber, which has a theoretical bandwidth far in excess of anything residential customers currently need. For FTTC, the last-mile medium is copper telephone wire, which has a hard physical ceiling determined by its gauge, length, and condition. No amount of software optimization can make copper carry 1 Gbps over 300 meters — the physics simply does not permit it. This is why upgrading from FTTC to FTTH requires civil engineering work to physically replace the copper with fiber, not just a software or equipment update.
Fiber Deployment Types Compared
| Type | Fiber Reach | Last-Mile Technology | Typical Downstream | Typical Upstream | Latency |
|---|---|---|---|---|---|
| FTTH / FTTP | All the way to premises | Fiber (none) | 300 Mbps – 10 Gbps | 300 Mbps – 10 Gbps | 1 – 5 ms |
| FTTC | To street cabinet | Copper VDSL2 | 40 – 80 Mbps | 10 – 20 Mbps | 10 – 20 ms |
| FTTB | To building basement | Short copper / Ethernet | 100 – 500 Mbps | 50 – 200 Mbps | 2 – 10 ms |
Frequently Asked Questions
What is FTTH?
FTTH stands for Fiber to the Home. It means the fiber optic cable runs all the way from the ISP's central office or distribution point directly to your individual home or apartment, terminating at an ONT installed on or inside your premises. There is no copper segment in the last mile — your connection is pure fiber from end to end. FTTH delivers the full speed and latency benefits of fiber internet, including symmetric gigabit or multi-gigabit speeds and round-trip times of 1–5 ms.
What is FTTC and why is it slower than FTTH?
FTTC stands for Fiber to the Cabinet (also called Fiber to the Curb). In an FTTC deployment, fiber runs from the ISP's facility to a street-side distribution cabinet — typically located within 50–300 meters of your home — and the final stretch from the cabinet to your premises uses the existing copper telephone wire with VDSL2 or G.fast technology. Because copper's data-carrying capacity degrades sharply with distance, the further you are from the cabinet, the slower your connection. A home 50 m from the cabinet might get 80 Mbps down; one 300 m away might get 40 Mbps or less.
Is FTTP the same as FTTH?
Effectively yes. FTTP stands for Fiber to the Premises, which is the broader term used primarily in the United Kingdom to describe any deployment where fiber reaches the customer's building — whether a house, apartment, or business. FTTH specifically means a single residential home. In practice, FTTP and FTTH describe the same technology and deliver the same performance: pure fiber all the way to the building with no copper last mile. Openreach in the UK uses "FTTP" as its official term for what would be called FTTH in the United States.
How do I know if I have full fiber or FTTC?
The clearest indicator is your equipment. If a technician installed an ONT — a small box that connects to your router via Ethernet and has a fiber cable entering it — you have full fiber (FTTH/FTTP). If you have a standard DSL modem connected to a phone socket via a telephone-style cable, you are on FTTC or ADSL with a copper last mile. You can also check with your ISP directly, ask your neighbors what service they receive, or use the FCC's broadband map (in the US) or Openreach's checker (in the UK) to see what technology is registered at your address.
Can FTTC be upgraded to FTTH?
Yes, but it requires civil engineering work. Upgrading FTTC to FTTH means physically running a new fiber strand from the street cabinet (or a new closer distribution point) all the way to your home. This involves trenching your property, threading conduit, and installing an ONT. ISPs typically roll out FTTH upgrades area by area rather than home by home, so the timeline depends on whether your ISP has that area in its build schedule. Some ISPs offer to expedite a single-premises upgrade for a one-time installation fee, though policies vary.
Why does distance from the cabinet affect FTTC speed?
FTTC's copper last mile uses VDSL2, which encodes data as high-frequency electrical signals on telephone wire. Copper has significant resistance and capacitance that attenuate high-frequency signals over distance — the farther the signal travels, the weaker and more degraded it becomes. VDSL2 can achieve around 80 Mbps at 50 meters from the cabinet but degrades to roughly 40 Mbps at 300 meters and drops below 20 Mbps beyond 500 meters. This distance sensitivity is fundamentally different from fiber, where signal quality is essentially the same whether you are 100 meters or 5 kilometers from the distribution point.