InfiniBand vs. Ethernet: A Comprehensive Guide for High-Performance Computing

InfiniBand, a leading In-Network Computing platform, is revolutionizing high-performance computing (HPC) and hyper-scale cloud infrastructures with its unmatched performance. Designed for server-side connections, InfiniBand enables seamless communication between servers, storage devices, and networks. Backed by the InfiniBand Industry Association, it has become the top interconnect solution on the prestigious TOP500 list, powering 44.4% of the systems, compared to Ethernet's 40.4%. Let’s explore the key differences between InfiniBand and Ethernet.

What is InfiniBand?

InfiniBand fostered under the guidance of the InfiniBand Trade Association (IBTA), serves as a standardized communication specification. This specification delineates a switched fabric architecture explicitly crafted to interconnect servers, communication infrastructure equipment, storage solutions, and embedded systems within the expansive landscape of a data center. This emphasis on standardization ensures seamless integration and efficient communication across diverse components in the HPC networking environment.

InfiniBand, recognized for its high bandwidth and low latency, boasts impressive speeds such as FDR at 56Gbps, EDR at 100Gbps, HDR at 200Gbps, and NDR at 400Gbps/800Gbps per second throughput with a 4x link width connection. Excitingly, even faster speeds are on the horizon.

InfiniBand excels in scalability, accommodating tens of thousands of nodes within a single subnet, making it the preferred choice for high-performance computing (HPC) environments. With quality of service (QoS) and failover capabilities, InfiniBand is a key network fabric for the non-volatile memory express over fabrics (NVMe-oF) storage protocol, alongside Ethernet, Fibre Channel (FC), and TCP/IP networks. Opt for InfiniBand in your data center for unmatched performance and scalability.

What is Ethernet?

Ethernet, conceived by Xerox, Intel, and DEC, serves as a LAN specification standard, establishing itself as the most widely adopted communication protocol for Local Area Networks (LANs) with data transmission occurring through cables. Originating in the 1970s, Xerox pioneered Ethernet as a wired communication technology, connecting devices within LANs or Wide Area Networks (WANs). Its versatility extends to linking various devices, from printers to laptops, spanning buildings, residences, and small communities. The user-friendly interface simplifies the creation of LANs using just a router and Ethernet connections, incorporating devices like switches, routers, and PCs.

Despite the prevalence of wireless networks in many locations, Ethernet endures as a prominent choice for wired networking due to its reliability and resistance to interference. Over the years, Ethernet has undergone multiple revisions, consistently adapting and expanding its capabilities. Today, it stands as one of the most extensively utilized network technologies globally.

Presently, the IEEE 802.3 Standard Organization, under the IEEE umbrella, has issued Ethernet interface standards, including 100GE, 200GE, 400GE, and 800GE, reflecting ongoing efforts to enhance and advance Ethernet technology.

InfiniBand vs Ethernet

InfiniBand emerged with the specific intent of alleviating the bottleneck in cluster data transmission within high-performance computing scenarios. Over time, it has evolved into a widely adopted interconnection standard, effectively catering to modern requirements. The key distinctions between InfiniBand and Ethernet manifest in their bandwidth, latency, network reliability, and networking methodologies.

Bandwidth

Concerning bandwidth, InfiniBand has experienced more rapid advancements compared to Ethernet, primarily driven by its utilization in high-performance computing environments and its ability to alleviate CPU load. In contrast, Ethernet is predominantly tailored for terminal device interconnection and doesn't necessitate the same high bandwidth demands as InfiniBand.

Latency

In the realm of network latency, InfiniBand and Ethernet diverge significantly in their processing flows. InfiniBand leverages Cut-Through technology in switches, substantially diminishing forwarding delay to less than 100 ns. In contrast, Ethernet switches undergo longer processing flows, attributed to the intricacies introduced by services like IP, MPLS, and QinQ.

Reliability

In the realm of high-performance computing where network reliability is paramount, InfiniBand takes the lead with its well-defined layer 1 to layer 4 formats, guaranteeing a lossless network through end-to-end flow control. Conversely, Ethernet lacks a scheduling-based flow control mechanism, relying on a larger chip area to temporarily store messages. This approach results in higher costs and increased power consumption for Ethernet.

Networking Methodologies

In terms of network management, InfiniBand proves to be more straightforward than Ethernet, thanks to the integration of the Software-Defined Networking (SDN) concept into its design. In InfiniBand, a subnet manager exists on each layer 2 network, facilitating the configuration of nodes and the calculation of forwarding path information. In contrast, Ethernet necessitates MAC entries, IP, and ARP protocols, adding layers of complexity. Ethernet also relies on regular packet sending for entry updates and employs the Vlan mechanism to segment virtual networks and restrict their scale. This complexity introduces challenges, including the potential for loop networks, requiring additional protocols like STP.

Investigating InfiniBand Offerings

InfiniBand Switches & NICs

In summary, the comparison between InfiniBand and Ethernet underscores the notable advantages of InfiniBand networks. For those considering the implementation of InfiniBand switches in their high-performance data centers, further details are available. The InfiniBand network has undergone rapid iterations, progressing from SDR 10Gbps, DDR 20Gbps, QDR 40Gbps, FDR56Gbps, EDR 100Gbps, and now to HDR 200Gbps and NDR 400Gbps/800Gbps InfiniBand. These advancements are made possible through the integration of RDMA (Remote Direct Memory Access)

FS offers NVIDIA Quantum™-2 NDR InfiniBand 400G and NVIDIA Quantum™ HDR InfiniBand 200G data center switches, available in both managed and unmanaged configurations. To meet diverse customer needs, the 400G switches come with service support options of one year, three years, and five years.

InfiniBand Modules

InfiniBand DAC

InfiniBand AOC

InfiniBand Standards Overview

InfiniBand NDR (Next-Generation Data Rate):

The InfiniBand NDR category includes InfiniBand 400Gbase/800Gbase transceivers and DAC, designed to be compatible with Mellanox NDR 400Gb switches such as the MQM9700/MQM9790 series. These components enable high-performance connections in GPU-accelerated computing, potentially saving up to 50% in costs. They are well-suited for High-Performance Computing (HPC), cloud computing, model rendering, and storage in InfiniBand 400Gb/800Gb networks.

InfiniBand HDR (High Data Rate):

FS's InfiniBand HDR connectivity product line provides a range of solutions, including 200Gb/s and 400Gb/s QSFP56 IB HDR MMF active/passive optical cable (AOC), active/passive direct-attached copper cable (DAC), optical transceiver routers, and 200G switches. Modules and cables connect switches like the MQM8700/MQM8790 to NVIDIA GPU (A100/H100/A30) and CPU servers, and storage network adapters like the ConnectX-5/6/7 VPI. They offer potential savings of up to 50% and are advantageous for GPU-accelerated high-performance computing (HPC) cluster applications, including model rendering, deep learning (DL), and NVIDIA application networking in InfiniBand HDR.

InfiniBand EDR (Enhanced Data Rate):

The InfiniBand EDR product line comprises InfiniBand 100Gbase QSFP28EDR AOC, EDR DAC, AOC, and transceivers. They offer cost-effective solutions for high-performance connections in GPU-accelerated computing.

InfiniBand FDR (Fourteen Data Rate):

The InfiniBand FDR product line includes InfiniBand 40Gbase QSFP+ FDR10 AOC, DAC, and transceivers, as well as 56Gbase QSFP+ FDR DAC and AOC. These products seamlessly integrate with Mellanox EDR switches.

Advantages of InfiniBand in High-Performance Computing Networks

As data communication, internet technology, and visual media evolve, the demand for greater computing power, storage capacity, and network efficiency has never been higher. InfiniBand stands out in this landscape, offering high-bandwidth network services, low latency, and the ability to offload protocol processing from the CPU, making it an ideal choice for high-performance computing (HPC) data centers. This capability leads to significant performance gains across various applications, including Web 2.0, cloud computing, big data, financial services, virtualized data centers, and storage solutions.

InfiniBand not only matches the speed of Ethernet at 100G but surpasses it, offering switches that range from 100G/200G to 400G/800G, meeting the rigorous demands of HPC architecture. This combination of high bandwidth, speed, and low latency enhances server efficiency and boosts application productivity.

Scalability is another strong suit of InfiniBand, with a single subnet capable of supporting up to 48,000 nodes at Network Layer 2. Unlike Ethernet, which relies on broadcast mechanisms like ARP that can lead to bandwidth inefficiencies, InfiniBand eliminates these issues and supports multiple subnets, adding a layer of flexibility.

Recognizing the critical role of high-performance computing, FS offers InfiniBand products powered by Quantum InfiniBand switch devices. These solutions deliver non-blocking bandwidth up to 16Tb/s and port-to-port delays under 130ns, ensuring high availability and multi-service support for HPC data centers. While Ethernet remains a viable option for distributing workloads across devices, FS’s multi-speed Ethernet switches provide the flexibility needed to build versatile and efficient networks.

Choosing the Right Network

InfiniBand and Ethernet each excel in specific scenarios. InfiniBand stands out by significantly enhancing data transfer rates, optimizing network utilization, and reducing the CPU load, making it the preferred solution in high-performance computing (HPC). On the other hand, Ethernet remains a practical choice for data centers where low communication delay is less critical, and flexible access and expansion are prioritized.

The unmatched performance of InfiniBand, combined with its cutting-edge architecture and streamlined design, empowers HPC data centers to optimize business performance by reducing delays and facilitating seamless bandwidth upgrades for critical nodes. As InfiniBand continues to gain popularity, its applications are expected to expand across various scenarios.

FS is committed to supporting high-performance computing with a range of InfiniBand solutions tailored to meet the demands of modern data centers. Our offerings include NVIDIA Quantum™-2 NDR 400G switches, as well as a variety of transceivers and cables designed for high-speed, low-latency connectivity. With FS's advanced InfiniBand products, you can ensure your data center operates at peak efficiency, driving optimal business performance. Explore our InfiniBand solutions to future-proof your network infrastructure.