(iG): A Guide to Internet Access

The Internet is a global system of interconnected computer networks that communicate using protocols defined in the Internet Protocol Suite (TCP/IP). A central component of this suite is the Internet Protocol (IP), which provides a system for addressing and routing data (datagrams) between networks.

The Internet developed from early U.S.-based research networks, mainly ARPANET and NSFNET, which were originally created for academic and research purposes. During the late 1980s and early 1990s, the modern Internet began to take shape as policy changes and increasing demand led to the transition from publicly funded networks to commercial network providers.

The development and promotion of Internet standards is supported by organisations such as the Internet Society, alongside other bodies including the Internet Engineering Task Force (IETF), which develops many of the core technical standards.

Over time, the way people connect to the Internet has changed significantly. Early users relied on desktop computers with dial-up connections, whereas by 2025, smartphones using wireless mobile networks have become a common means of access.

Internet Service Providers (ISPs) are companies or organisations that run Internet Protocol (IP) networks and provide access to the Internet for users, who are typically referred to as subscribers.

In the period before the early 1990s, the Internet mainly functioned as a research and education system based on TCP/IP, with very limited commercial involvement. Core infrastructure, including networks such as NSFNET and earlier systems like ARPANET, was publicly funded and not intended for commercial use. During the late 1980s and early 1990s, changes in government policy in the United States, combined with increasing commercial interest, resulted in a shift towards privately operated backbone networks. This transition allowed private companies to begin offering Internet access to the public.

One of the earliest commonly referenced ISPs is The World, which began providing Internet access around 1989, although its status as the first ISP is sometimes disputed. Other early providers in the United States included CompuServe, AOL, EarthLink, PSINet, and UUNET. In the United Kingdom, early ISPs such as Pipex and Demon Internet emerged in the early 1990s, alongside several smaller providers. These services primarily relied on dial-up technology and initially served a limited user base. Despite their small scale, these early ISPs were important in the development of national Internet infrastructure. For example, Pipex, in collaboration with British Telecom, contributed to the establishment of the London Internet Exchange (LINX), which enabled different ISPs to exchange traffic directly and improved network efficiency while reducing costs. By the late 1990s, Internet access through large commercial ISPs had become widely available across most developed countries.

In the UK, Freeserve became the first widely popular provider, offering Internet access without a monthly subscription fee (users still paid call charges).

During the 2000s, many smaller ISPs were acquired by larger telecommunications companies, leading to a more consolidated market. For example, Pipex was acquired by Tiscali, which was later acquired by Carphone Warehouse and rebranded as TalkTalk.

Today, while smaller and niche ISPs (such as satellite or wireless providers) still exist, most UK users are served by a small number of major companies, including BT Group (including EE and Plusnet), Sky, Virgin Media, and TalkTalk, alongside others such as Vodafone.

ISPs vary in size and structure, including infrastructure providers (wholesale networks), retail service providers (consumer-facing ISPs), and vertically integrated providers that own infrastructure and also sell services directly to customers.

Consumer-facing ISPs typically offer broadband on monthly or annual contracts, with prices depending on speed, technology, and bundled services. Many packages advertise "unlimited" data, although this is often subject to a fair usage policy that may include traffic management during peak times.

Historically, ISPs focused on fixed-line (wired) access. Today, the landscape includes Mobile ISPs providing internet via cellular networks (4G, 5G, and 6G in development). A significant portion of the population are now "mobile-only" subscribers, relying entirely on cellular data for both personal and home internet, often utilizing 5G fixed-wireless access as a direct replacement for traditional wired broadband.

The following access technologies have been used by UK Internet Service Providers. The most common today (2026): 4G/5G and fibre. Amongst the fastest for consumers: Full fibre (FTTP/FTTH). Business-grade: Leased lines (symmetrical, dedicated). Obsolete: Dial-up, ISDN, Frame Relay, ATM:

Wireless

- Satellite: VSAT, TDMA, SCPC; modern LEO systems (e.g. Starlink)
- Mobile / Cellular (incl. Fixed Wireless Access): 2G, 3G, 4G, 5G
- WiMAX (fixed wireless): IEEE 802.16
- Wi-Fi (local wireless access): IEEE 802.11 (a, b, g, n, ac, ad)

Wired

- (Broadband) DSL (Digital Subscriber Line): ADSL, SDSL, VDSL/VDSL2, G.fast
- Cable: DOCSIS (via cable TV networks, e.g. Virgin Media)
- Fibre Optic / Ethernet: FTTC, FTTP, FTTH, FTTB (delivered via providers such as Openreach and CityFibre)
- Leased Lines (dedicated): E1, Ethernet (T1 mainly US)
- Legacy backbone/business tech (largely obsolete): Frame Relay, ATM

Wired (Narrowband / Legacy)

- Dial-up: ITU-T standards (V.22, V.32, V.34, V.90, V.92)
- ISDN (Integrated Services Digital Network)

Broadband is a term used by telecom companies to describe an Internet connection with high data capacity, multiple channels or frequencies, and, in the case of wired services, an always-on connection. The opposite of this is narrowband, such as dial-up, which is much slower, uses a single channel, and means the telephone line cannot be used for calls at the same time. Broadband is generally used to describe faster, modern Internet access, although it is a flexible term that has changed over time as technology has improved.

Definitions of broadband vary depending on the organisation. Historically, the EU defined broadband as connections between 144 kbit/s and 30 Mbit/s. More recently, "superfast broadband" has been defined as 30 Mbit/s and above, and "ultrafast" as 300 Mbit/s and above. In the UK, Ofcom broadly categorises broadband into standard broadband (below 30 Mbit/s), superfast or Next Generation Access (NGA), and mobile broadband such as 3G, 4G and 5G services.

In the UK, broadband first became widely available around 2000 using DSL technology over the existing copper telephone network. Early ADSL services typically offered speeds of around 512 kbit/s (0.5 Mbit/s), which was a major improvement over dial-up but still relatively slow. Over time, speeds increased significantly: ADSL Max introduced speeds of up to around 8 Mbit/s in the mid-2000s, and later ADSL2+ increased this to around 24 Mbit/s by the late 2000s. These improvements still relied on copper telephone lines, so performance was affected by the quality and length of the line.

A key limitation of DSL-based broadband is that speed decreases the further the user is from the exchange. This led to the development of FTTC (fibre to the cabinet), where fibre optic cable runs to a street cabinet, and the remaining connection to the home is delivered over copper using VDSL. In FTTC systems, performance is not based on distance from the exchange, but instead depends on the length and quality of the copper line between the cabinet and the property. Alongside DSL, cable broadband developed using DOCSIS technology, most notably through providers such as Virgin Media. DOCSIS has evolved through versions such as 3.0 and 3.1, enabling much higher speeds, although cable networks typically use shared bandwidth within a local area, meaning speeds can vary at peak times.

Fibre optic broadband has since become the most important wired technology, delivered through FTTC, FTTP and FTTH systems by infrastructure providers such as Openreach and CityFibre. Full fibre (FTTP/FTTH) is not affected by distance in the same way as copper-based systems and provides the highest speeds and most stable performance. In many cases, fibre connections are delivered using Ethernet-style technologies, especially for higher-capacity services.

Leased lines are another important wired broadband technology, mainly used by businesses. These provide a dedicated connection that is not shared with other users, with symmetrical speeds where upload and download rates are equal. They also come with guaranteed performance levels, known as service level agreements, making them suitable for organisations that require reliability and consistent bandwidth.

Over time, broadband has been regulated and shaped by UK policy. Before 2003, the industry was overseen by Oftel, which was then replaced by Ofcom. Government initiatives such as Digital Britain and Broadband Delivery UK (BDUK) aimed to improve national coverage and speed, alongside a Universal Service Obligation requiring a minimum broadband speed for all premises.

Overall, wired broadband in the UK has evolved from early DSL systems into a mix of cable, fibre and leased line technologies. Fibre is now the dominant high-speed option, DSL is gradually being phased out due to distance limitations, and cable remains widely used through continuous DOCSIS upgrades.

Wireless internet access uses radio waves to transmit data through the air, removing the need for physical cables. In modern networks, it provides both mobile connectivity and fixed broadband alternatives, especially in areas where wired infrastructure is limited or expensive to install. Satellite is essential for remote coverage, mobile networks provide widespread access and mobility, WiMAX offers niche fixed wireless solutions, and Wi-Fi enables local device connectivity. Together, these technologies complement wired broadband and ensure widespread internet availability.

Satellite broadband is designed to provide internet access in areas where other technologies are not available. Traditional systems use geostationary satellites and technologies such as VSAT, with TDMA or SCPC used to manage bandwidth. However, these satellites are located very far from Earth, which results in higher latency and slower response times. More modern Low Earth Orbit (LEO) systems, such as Starlink, operate much closer to Earth. This significantly reduces latency and improves speeds compared to traditional satellite systems, making them a viable option for rural and remote locations. However, performance can still vary depending on weather, congestion, and line-of-sight conditions.

Mobile internet access has developed through generations of cellular technology. 2G provided basic data services, 3G enabled mobile browsing, and 4G delivered stable broadband-like speeds. The current 5G networks offer significantly higher speeds and lower latency, enabling more advanced applications. A major development is Fixed Wireless Access (FWA), where a 5G connection is used in a fixed location, such as a home router instead of a mobile phone. This allows internet access without physical cabling and can act as an alternative to traditional fixed-line broadband in some areas, particularly where fibre is not yet available.

WiMAX (Fixed Wireless) WiMAX (IEEE 802.16) is a fixed wireless broadband technology designed for long-range connections. It uses a base station to transmit signals to a receiver at the customer's premises. Although it was not widely adopted for mobile use, it has been used in some regions to deliver broadband to rural areas, business parks, and locations where installing physical cables would be costly or impractical.

Wi-Fi (Local Wireless Access) Wi-Fi (IEEE 802.11) is the most common form of local wireless networking. It is used to distribute an internet connection within a home, office, or public space. The internet connection itself may come from fibre, cable, mobile, or satellite, but Wi-Fi is used to wirelessly connect devices such as laptops, smartphones, and tablets to a local router or access point. Modern Wi-Fi standards such as 802.11ac (Wi-Fi 5), 802.11ax (Wi-Fi 6), and 802.11be (Wi-Fi 7) allow multiple devices to connect simultaneously with high speeds and improved reliability.