Why InfiniBand vs Ethernet matters for Data Centers?

InfiniBand vs Ethernet for Data Centers

Over the four decades since its introduction in 1980, Ethernet has become a ubiquitous term for network connectivity. However, over the past decade, InfiniBand has emerged as a competing standard with specific advantages for data centers that support complex compute tasks like Machine Learning and Artificial Intelligence. InfiniBand's architecture was developed by integrating several competing designs for high-speed networking, resulting in a unified standard.

What is the difference between Ethernet and InfiniBand? If you search the web, you’ll find many technical articles focused on hardware specifications.

That explains the difference at a technical level, but what are the key differences between these standards when it comes to performance and architecture, and why do these criteria matter for data centers?

What is Ethernet?

Ethernet is a wired network specification standard published on September 30, 1980. It was developed by Xerox, Intel, and DEC company. It is a system for physically connecting computer systems with protocols for how information should be exchanged.

One of the main functions of Ethernet is to control how information is exchanged between two or more systems. If those systems try to transmit data to each other at the same time, a “data packet collision” would occur. Ethernet has rules that allow networked devices to talk to each other without collisions. Gigabit Ethernet allows for high-speed wired connections within local area networks. This provides faster data transfer compared to earlier Ethernet standards.

Evolving Ethernet Standards

Every 7 to 8 years the IEEE Standards Association introduces a new standard of high speed for Ethernet.

• In 2002, 10 Gigabit per second Ethernet (GbE) was introduced.
• In 2010, 40 GbE and 100 GbE became the standard.
• In 2017,  200 GbE and 400 GbE were introduced.
• Most recently, in 2024, the IEEE announced Ethernet speeds up to 800 gigabits per second (Gbps), claiming "the industry needed it!"

Why? After the introduction of 40 GbE and 100 GbE, the first IEEE 802.3™ Ethernet Bandwidth Assessment forecasted that bandwidth needs will grow, on average, by a factor of about 10 every 5 years.

Ethernet's widespread adoption across various network applications has driven its ongoing development and promoted interoperability between vendors.

What is InfiniBand?

Infiniband is an open standard network communications technology introduced in 1999. Promoted by the InfiniBand Trade Association for use in high-performance computing (HPC), it features high throughput and low latency.

The architecture is a high-speed, low-latency interconnected fabric. This composition is commonly seen in clustered computing environments.

InfiniBand for Data Centers: Network Composition

InfiniBand for data centers comes down to a handful of benefits: high bandwidth, low latency and I/O consolidation. These allow the data centers to consolidate over a unified fabric at a cost-savings. Architecturally, an InfiniBand network supports tens of thousands of nodes via central hubs called switches. Host channel adapters (HCAs) and target channel adapters (TCAs) serve as the interfaces that initiate and terminate data transmissions. Since the flow of data is managed at the switch, multiple systems can transmit data at the same time via the InfiniBand fabric.

The InfiniBand standard is owned by the InfiniBand Trade Association. Since 2020, Nvidia has been the largest manufacturer of InfiniBand components thanks to their acquisition of Mellanox Technologies.

Infiniband Data Rates

At present, InfiniBand supports multiple different data rates, including double data rate (DDR) and other high-speed standards, from Infiniband SDR (Single Data Rate) with 10 Gbps to InfiniBand NDR (Next Data Rate) with speeds from 400 Gbps to 800 Gbps.

These capabilities enable efficient data processing in demanding environments.

InfiniBand vs. Ethernet for Data Centers

InfiniBand and Ethernet are network standards with similar top speeds. Both have valid uses and offer competitive advantages over each other, especially when comparing flexibility in configurations and architectural benefits and challenges.

With that in mind, here are four specific reasons why cloud GPU providers like Voltage Park are designed with InfiniBand.

• No Packet Loss. InfiniBand offers “zero-packet loss design.” Essentially, it’s designed so data never needs to be resent. That makes it more efficient for high-performance computing, where fast communication between networked nodes is critical - especially for tasks like Machine Learning and AI training. InfiniBand provides higher bandwidth compared to Ethernet, which is crucial for data-intensive workloads in high performance computing environments that demand rapid data transfer and low latency.

• Lower Protocol Overhead. Ethernet can require extra protocols to avoid loops or manage congestion, which adds overhead as the network expands. Traditional Ethernet often has lower bandwidth than InfiniBand, which can limit data transfer speeds in demanding environments. InfiniBand reduces or eliminates these overheads, resulting in networks that scale up with fewer performance losses.

• Better Scalability. InfiniBand is better suited for massive, interconnected systems, such as those found in AI clusters or HPC environments. Scalable Hierarchical Aggregation and Reduction Protocol (SHARP) allows for seamless scaling of data aggregation. InfiniBand's lower latency and ability to minimize latencies are especially important for AI and HPC workloads that require rapid, efficient communication.

• Optimized GPU Integration. Because Nvidia is a primary manufacturer of InfiniBand hardware solutions, they are specifically designed to work seamlessly with industry-standard Nvidia GPUs like NVIDIA HGX H100. This tight integration maximizes performance for GPU-accelerated workloads. In data center integration, InfiniBand connects servers and storage systems to achieve fast, reliable data transmission.

When considering cost-effectiveness, the total cost of ownership is a key factor: Ethernet's backward compatibility can reduce costs by leveraging existing infrastructure, while InfiniBand may require proprietary hardware that increases expenses.

Looking at AI networking trends, the vast majority of switch ports in AI networks are expected to operate at very high speeds in the near future, supporting the growing need for high-bandwidth networking in AI infrastructure.

For use cases, high performance computing environments often rely on InfiniBand for its superior bandwidth and low latency, making it ideal for latency-sensitive and data-intensive applications.

Ready for InfiniBand? Voltage Park can Help

Voltage Park runs on NVIDIA Quantum-2 InfiniBand, providing low latency for both On-Demand GPU and Dedicated Reserve Cloud.

‍