Important Internet Protocols and Addressing Systems

Internet protocols and addressing systems form the backbone of the global internet. They decide how data packets move, how devices are identified, and how networks exchange traffic safely across borders and platforms.

For Prelims revision, the key areas are IP versions, address management bodies, routing security, and India’s internet infrastructure institutions. These topics are frequently linked to digital capacity, network architecture, and the transition to newer internet technologies.

Internet Protocol Versions: IPv4 and IPv6

The Internet Protocol (IP) handles the addressing and routing of data packets across networks. IPv4 was defined in RFC 791 in 1981 and remains widely used, but its limited address space created the need for IPv6, which is standardized in RFC 8200.

IPv4 addresses are written in four decimal blocks separated by dots, while IPv6 uses longer hexadecimal values separated by colons. The much larger IPv6 pool is important for modern networks, mobile devices, cloud systems, and the expanding Internet of Things ecosystem.

Exam fact: IPv4 uses a 32-bit address space, while IPv6 uses a 128-bit address space.

Why IPv6 Matters for Digital Capacity

IPv6 is not just a technical upgrade; it is central to network expansion and digital capacity. As the number of connected devices rises, older IPv4 space becomes insufficient, forcing networks to use workarounds such as address sharing. IPv6 helps create a more scalable internet architecture.

• Massive address pool: Supports far more devices and services than IPv4.
• Better scalability: Suits modern telecom, cloud, and enterprise networks.
• Improved network design: Reduces dependence on address-sharing techniques.
• Protocol continuity: Enables smoother long-term internet growth.

Regional Internet Registries and APNIC

Regional Internet Registries (RIRs) are nonprofit bodies that manage and distribute internet number resources such as IP addresses and Autonomous System Numbers (ASNs) within defined regions. Globally, there are five RIRs, coordinated by the Number Resource Organization (NRO).

• APNIC (Asia Pacific Network Information Centre): Serves the Asia-Pacific region and is headquartered in Brisbane, Australia.
• AFRINIC (African Network Information Centre): Serves Africa.
• ARIN (American Registry for Internet Numbers): Serves Antarctica, Canada, parts of the Caribbean, and the United States.
• LACNIC (Latin American and Caribbean Internet Addresses Registry): Serves Latin America and parts of the Caribbean.
• RIPE NCC (Réseaux IP Européens Network Coordination Centre): Serves Europe, Central Asia, and the Middle East.

APNIC is one of the most important RIRs for Asia-Pacific internet governance. It administers IP addresses and supports operational policies for the region. APNIC has been led by Director General Jia Rong Low since October 2024.

NIXI, IRINN and India’s Internet Number Resources

The National Internet Exchange of India (NIXI) is a not-for-profit Section 8 company under the Ministry of Electronics and Information Technology (MeitY). It was established in June 2003 to strengthen India’s internet ecosystem and improve domestic traffic handling.

• Internet Exchange Points (IXPs): Enable domestic ISPs and content delivery networks to exchange traffic directly, helping keep local traffic within the country.
• IN Registry: Manages the country-code top-level domains .IN and .भारत.
• IRINN: The Indian Registry for Internet Names and Numbers, which functions as the National Internet Registry (NIR) under APNIC for allocation of IP addresses and ASNs in India.

These institutions are important for internet governance, domain administration, and efficient use of national network resources.

Routing Security and Core Protocols

Internet traffic moves across networks through routing protocols that decide the best path for data exchange. Because these systems can be targeted by attackers, routing security is essential for safe and reliable communication between autonomous systems.

• Border Gateway Protocol (BGP): The standard protocol used to exchange routing information between autonomous systems on the internet.
• Resource Public Key Infrastructure (RPKI): A cryptographic framework used to verify whether an autonomous system is authorized to announce specific IP address blocks.
• Domain Name System (DNS): Converts human-readable domain names into machine-readable IP addresses.
• DNS Security Extensions (DNSSEC): Protects DNS records and helps prevent spoofing and related attacks.
• Route hijacking: A major threat in which traffic is misdirected by false routing announcements.

Exam fact: RPKI strengthens BGP by helping verify the authenticity of route announcements.

Key Prelims Takeaways

• IPv4 uses a 32-bit address space and offers about 4.3 billion addresses.
• IPv6 uses a 128-bit address space and is designed for much larger network expansion.
• IPv4 is written in dotted-decimal form, while IPv6 uses hexadecimal notation with colons.
• There are five RIRs globally, and APNIC covers the Asia-Pacific region.
• APNIC has been led by Jia Rong Low since October 2024.
• NIXI was established in June 2003 as a Section 8 company under MeitY.
• IRINN is India’s National Internet Registry under APNIC for IP address and ASN allocation.
• .IN and .भारत are managed by NIXI through the IN Registry.
• BGP is the main inter-domain routing protocol on the internet.
• RPKI is used to reduce route hijacking and improve routing security.
• DNS translates domain names into IP addresses, while DNSSEC adds protection against spoofing.
• ISPAI is a national trade body representing domestic ISPs, established in 1998.

Recent Context

The 62nd APNIC Conference (APNIC 62) is being organized in Mumbai from September 4 to 10, 2026, with NIXI as host. The event focuses on network automation, AI, routing security, cybersecurity, and internet governance, and NIXI and APNIC are formalizing an MoU to accelerate IPv6 deployment in India.