π·οΈTwo Poor Decisions That Borked the Modern Internet | IPv4 & Ethernet π‘
The modern Internet, as revolutionary as it is, carries the burden of two critical decisions made decades ago that continue to impact its performance and scalability. These decisions involve the adoption of IPv4, leading to IP address starvation, and the use of Ethernet with its limited Maximum Transmission Unit (MTU) of 1500 bytes. Despite advancements in technology, these issues persist, hindering the potential of the Internet.
The Burden of IPv4: IP Address Starvation
A Brief History of IPv4
IPv4 (Internet Protocol version 4) was introduced in 1983 as part of the ARPANET project, which was the precursor to the modern Internet. IPv4 uses a 32-bit address scheme allowing for a total of 4.3 billion unique addresses. At the time, this seemed more than sufficient. However, the explosive growth of the Internet and the proliferation of connected devices quickly revealed the limitations of this addressing scheme.
The Problem of Address Starvation
By the mid-1990s, it became evident that the pool of available IPv4 addresses would eventually be exhausted. Today, the scarcity of IPv4 addresses necessitates the use of techniques like Network Address Translation (NAT) to conserve addresses, adding complexity and potential points of failure. The limited address space also stymies innovation and complicates the deployment of new Internet-connected devices and services.
Ethernet and the MTU Limitation
The Adoption of Ethernet
Ethernet, developed by Xerox PARC in the 1970s, became the standard for local area networking (LAN). It was adopted widely because of its simplicity, low cost, and ease of implementation. Ethernet's initial design, however, set the MTU to 1500 bytes. This was sufficient for early networking needs but has since become a bottleneck.
The Performance Bottleneck
The MTU of 1500 bytes means that larger packets must be fragmented into smaller ones, increasing overhead and reducing performance. Although the concept of jumbo frames (MTUs greater than 1500 bytes) exists, it is not implemented end-to-end on the Internet due to compatibility issues and the lack of uniform support. This fragmentation leads to inefficiencies, especially in high-speed networks and data-intensive applications.
The OSI Alternative: CLNP
What is CLNP?
Connectionless Network Protocol (CLNP) was part of the OSI (Open Systems Interconnection) suite of protocols. CLNP, like IPv4, was designed to facilitate network communication but offered several advantages. It used a variable-length address space, which could theoretically accommodate an unlimited number of devices, thus avoiding the address exhaustion problem faced by IPv4.
The Choice in 1992
In 1992, a decision was made to favor IPv4 over CLNP, primarily due to the widespread adoption and momentum of TCP/IP protocols. This choice entrenched the limitations of IPv4 and foreclosed the adoption of what could have been a more scalable and flexible addressing scheme.
IPv6 | A Missed Opportunity
Why IPv6 Falls Short
IPv6 was introduced in the late 1990s to address the limitations of IPv4, primarily its limited address space. IPv6 uses 128-bit addresses, allowing for an astronomical number of unique addresses. However, IPv6 has not been widely adopted, partly due to the complexity of transitioning from IPv4 and the lack of immediate benefits perceived by many organizations.
Comparison to CLNP
While IPv6 resolves the address exhaustion issue, it does not offer the same flexibility as CLNP's variable-length addressing. Furthermore, IPv6 maintains many of the complexities of IPv4, including the reliance on NAT in transitional phases, and has not significantly simplified network management.
Wrap | Saddled with Poor Decisions
The Internet's foundational technologies, IPv4 and Ethernet, were groundbreaking in their time but now represent significant limitations. The decision to use IPv4 led to IP address starvation, while Ethernet's MTU limitation hampers performance. Although alternatives like CLNP could have offered more scalable solutions, the industry has continued to work within the constraints of these early decisions. As we move forward, recognizing and addressing these limitations is crucial for the continued evolution and optimization of the Internet.
Ronald Bartels ensures that Internet inhabiting things are connected reliably online at Fusion Broadband South Africa - the leading specialized SD-WAN provider in South Africa. Learn more about the best SD-WAN in the world: π Contact Fusion πΌπ
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Written by
Ronald Bartels
Ronald Bartels
Driving SD-WAN Adoption in South Africa