The modern internet and its future
Today's internet is shaped by giant content networks, cloud platforms, encryption everywhere, and new technologies, along with debates about governance, access, and resilience.
A flatter internet
The early internet was a strict hierarchy of ISPs. Today, large content and cloud providers such as Google, Meta, Amazon, Microsoft, and Netflix carry a huge share of traffic over their own global backbones, connecting directly to access ISPs at many IXPs and private interconnects. Much traffic now travels only from a nearby edge server to the user, bypassing traditional tier-1 transit.
Cloud and data-centre networking
Cloud data centres host hundreds of thousands of servers connected by high-capacity Clos fabrics, with virtual networks for each customer. Traffic between servers inside data centres, east-west traffic, far exceeds traffic to users. Providers link regions with private fibre, including undersea cables, and offer services such as global load balancing and edge computing.
Encryption everywhere
Following revelations of mass surveillance in 2013 and the arrival of free certificates, encryption became the norm: most web traffic uses HTTPS, DNS lookups are increasingly encrypted, and QUIC encrypts even most transport headers. This protects users but reduces what operators can see for troubleshooting and security, shifting monitoring toward endpoints and metadata.
Undersea cables and resilience
Around 99% of intercontinental data travels through several hundred undersea fibre-optic cables rather than satellites. Damage from ship anchors, earthquakes, or sabotage can disrupt connectivity for whole regions, so operators build diverse routes. Resilience also depends on avoiding single points of failure in DNS, cloud services, and content delivery, as large outages at single providers have repeatedly shown.
Internet governance
No single entity runs the internet. The IETF develops protocols; ICANN coordinates domain names and the root zone; regional internet registries allocate IP addresses and AS numbers; governments regulate ISPs within their territory. Debates continue over net neutrality, the principle that ISPs should treat traffic equally; online censorship and shutdowns; and data localisation rules.
Access and the digital divide
The International Telecommunication Union estimated that about 2.6 billion people, roughly a third of the world's population, were still offline in 2024, mostly in lower-income and rural areas. Mobile broadband, low Earth orbit satellites, community networks, and cheaper devices are expanding access, but affordability, skills, and relevant content remain barriers.
Looking ahead
Emerging directions include deploying post-quantum cryptography, further IPv6 adoption, 6G research aiming at around 2030, satellite-terrestrial integration, programmable and AI-assisted network operations, and the growth of AI workloads, which demand enormous bandwidth inside and between data centres. Each change builds on the same principles: layering, packet switching, end-to-end design, and open standards.
Worked example
When a user in Nairobi watches a popular video, the request likely resolves through DNS to a CDN cache inside the user's ISP or at a local IXP; the video travels only a few kilometres. A request for an obscure video may need to reach a regional cache in Europe, crossing an undersea cable. If that cable is cut, traffic reroutes over other cables with higher latency, while locally cached content keeps working, illustrating how caching and route diversity provide resilience.
Key takeaways
The internet has flattened as content and cloud giants run global backbones and connect directly to access ISPs. Data centres use Clos fabrics with dominant east-west traffic and private inter-region links. Encryption, including HTTPS, encrypted DNS, and QUIC, became the norm after 2013, limiting operator visibility. About 99% of intercontinental traffic uses undersea cables, so route diversity matters. Governance is shared among the IETF, ICANN, registries, and governments, with debates over neutrality and censorship. About 2.6 billion people were offline in 2024. Future work includes post-quantum security, IPv6, 6G, satellites, AI-assisted operations, and AI-driven traffic growth.
Flashcard
Content providers connecting directly to access ISPs
Check your understanding
Why does most popular video traffic today travel only a short distance to viewers?