7Jun, 2024
    Data Center Switch Purchase Essentials

    As data center networking architectures evolve towards increased disaggregation, data center switches have emerged as a distinct category. Distinct from conventional network switches tailored for three-tier hierarchical setups, these switches are engineered to cater to the stringent data and storage demands of mission-critical applications. Given the myriad of data center switches and vendors currently available, selecting an optimal one can pose a challenge. This guide aims to demystify data center switches, outline their essential requirements, and offer practical purchasing advice to facilitate your decision-making process.

    What Is a Data Center Switch?

    Broadly speaking, the data center switch represents a high-performance networking solution tailored primarily for large-scale enterprises and cloud service providers heavily invested in virtualization. Deployable across the entire data center infrastructure or serving as the cornerstone of either a two-tier (spine-leaf) or single-tier flat mesh/fabric design, these switches share several pivotal characteristics:

    They effectively manage both north-south and east-west traffic patterns, ensuring seamless data flow.

    Versatile in deployment, data center switches are adaptable to both top-of-rack (ToR) and end-of-row (EoR) configurations.

    Boasting high-bandwidth capabilities, they facilitate interconnections through both standard LAN Ethernet and SAN protocols, including Fibre Channel and its Ethernet variant, enabling efficient data exchange.

    Moreover, the distributed components of a data center switch are conveniently managed through a unified interface, streamlining administrative tasks and enhancing user-friendliness.

    Things To Consider When Buying Data Center Switches

    Choosing a data center switch can be a difficult task, no matter if you are deploying a new data center or deciding to upgrade the existing network infrastructure. There are many factors to consider and here lists some of the most important ones in several aspects.

    Data Center Architecture and Configuration

    Modern data centers use spine-leaf architecture and the switches located at each layer have their own requirements. Generally, spine switches are supposed to handle more traffic with higher capacity and better performance than leaf switches.

    Whether to use ToR or EoR configuration determines what types of data center switches you will need. If you already have an end-of-row network cabling in place, it’s better to make use of the existing wiring and deploy larger capacity data center EoR switches. If you plan to build a new data center or new cabling, Using ToR data center switches for the ToR network is a better idea, for they will offer more flexibility in terms of physical port coverage across the data center.

    Functions

    All switches have the same basic functionality, such as using standards-based protocols or maintaining a MAC address-to-port table. Based on their use cases and applications, different switches have unique characteristics. You should ask yourself a few questions to decide what functions are needed. Are you going to use enterprise-level applications? Are you considering redundancy? Do you have a virtualized infrastructure? For example, a reliable data center switch should have the capability to automate as well as support newer protocols such as EVPN and VXLAN. And some data center switches support Ansible/OpenFlow configuration and automation tools for easy management.

    Size, Number of Ports, and Data Rate

    Data center switches come in varying sizes. Choosing the right size for your business will depend on the current and future data flow. A large switch requires more resources to install and will serve your current and future needs. A smaller switch is economical, but you’ll have to install it in a top-of-rack manner to prevent bottlenecks.

    The size of the fiber connections that you’ll need should also be well considered. It’s advisable to make up your mind early enough on the connectivity that you will be using. Fiber connectivity varies from 10 Gbps, 25 Gbps to 40 Gbps, and even more. Nowadays the adoption of 100Gps has gained momentum in most data centers and some hyperscale data centers are moving towards higher speed 400Gbps, which paves the way for the development of 400G data center switches.

    Data center switches also have varying port types and numbers, based on which specific cabling and transceivers are selected, so you should know what you need now and make a reasonable estimate of what you’ll need in the future.

    Hardware and Software

    With cloud data centers growing and the trends of virtualization and new applications showing up these years, new data center switch types are coming to the market, such as white box switches and bare metal switches, of which the OS is open. As for data centers where large amounts of traffic are required to handle all the time, the white box switches or bare metal ones give network engineers an alternative choice other than brand-name switches, which brings both offering flexibility as well as low costs. Meanwhile, for data centers to upgrade, it is important to make clear what brands of switches, and what OSs are currently used on the network.

    Cooling and Airflow

    Before buying a switch, you should know that the way you install and connect the switches will affect the quality of airflow and cooling. If the cables block the airflow, that could mean a reduced lifetime due to overheating, which could cause premature failure.

    Similarly, the airflow direction of the switches influences the data center cooling. For instance, if the connections are located in the front of the servers, you should choose front-to-back cooling. However, if the connections are located on the back of the servers, you should go for back-to-front cooling.

    A small disruption for a couple of hours or days may not cause serious harm inside the data center. However, a design problem that’s overlooked for months and even years could mean frequent downtimes and even costly repairs and upgrades.

    other considerations

    • Redundancy: You should consider the level of redundancy that you need for your data center switches. You need to ensure that your switches have redundant power supplies, fans, and other critical components.
    • Management: You need to consider the management capabilities of your switches. You should choose switches that have a robust management interface that allows you to monitor and manage your network effectively.
    • Security: You should consider the security features of your switches. You need to ensure that your switches have advanced security features that can protect your network from cyber threats.

    Switch Vendor

    After considering all of these vital factors above, you’ve got a sense of what should you keep in mind. But remember, the data center switch’s performance, price, and support service vary from one vendor to the other, so please check out your vendor list and make sure you’ll work well with the selected vendor.

    Go through the user testimonials and reviews to find one with a good reputation. Evaluate them by their services, i.e., software advancements and configurations, hardware spare and replacements, and troubleshooting support. You may consider buying the switches from different vendors as the SDN is emerging. However, unless you use a truly open SDN platform, buying from a single vendor is a wise choice for it is future-proofing. We should select a data center switch vendor that offers the most premium features and services at the most competitive price.

    Picking the Right Data Center Switch

    Now that you know what factors to consider in choosing a data center switch, what’s left is to narrow down your options to find the type you want. When picking a data center switch from the flooded market, a rule of thumb is to seek professional advice, i.e., if you aren’t an expert in the field. Where possible, have one of your IT guys around. A professional will better understand some technical terms such as buffer size, latency, and even port speeds, helping you avoid confusion so you can pick the right product.

    Aiming at the requirements of next-generation enterprise, data center, metropolitan area and HCI (hyper-converged infrastructure) networks, Gigalight launches the GS-680 series 100GE data center switches, which support mainstream protocols and applications and facilitate deployment and management. You are welcome to purchase.

    GS-680 Series 100G Switch

    32 100G ports are provided with low latency and non-blocking performance, 40G ports are used for access switches or servers, and 100G uplinks are used for core switches.

    MLAG achieves uninterrupted service

    Switches under MLAG can be upgraded without disrupting MLAG traffic. During the upgrading process, another switch in the system takes over traffic forwarding to ensure that services are not interrupted.

    1+1 hot-swappable power supply 3+1 redundant fans

    Dual power supplies can be replaced without shutting down the system, and the variable-speed fan uses front-to-back airflow and automatically adjusts fan speed to reduce power consumption.

    Breakout mode leverages existing equipment

    The 100G ports can be splitted into four 25G ports to provide higher compatibility and reduce hardware costs, and can be flexibly suitable for your existing campus network.

    QoS implements traffic control

    It could provide users or data flows different priorities for different applications to reduce packet loss, latency and shock on the network.

    MPLS establishes point-to-point connection

    MPLS enables small and medium-sized enterprises to build networks for their users, establish point-to-point connections, and realize network communication between users.

    23Jan, 2024
    Exploring the Advantages of 200G (8x25G NRZ) Optical Technology in Data Centers

    GIGALIGHT, which has focused on optical communication for eight years, directs your attention to the 200G (8x25G NRZ) technology, delving into its advantages such as low power consumption, low latency, and easy deployment. This provides a deeper understanding of cost-effective optical interconnection solutions within data centers.

    There are two technological directions for 200G optical modules: one utilizes the QSFP-DD packaging for an economical 8x25G NRZ network, while the other employs QSFP56 packaging for a 4x50G PAM4 network (to be discussed in a subsequent article).

    Compared to PAM4 technology, 200G (8x25G NRZ) boasts advantages in low power consumption, low latency, and easy deployment.

    Technical details:

    QSFP-DD packaging for 8x25G NRZ network: The 200G optical module uses QSFP-DD packaging, transmitting 25G NRZ signals through 8 channels. NRZ, representing non-return-to-zero signals, involves signal switching between high and low levels. Compared to traditional PAM4 signals, NRZ signals are easier to modulate and demodulate.

    Low power consumption: Utilizing 25G NRZ optical components, the module’s power consumption is reduced by 2–3W compared to modules based on PAM4 DSP CDR technology. This offers significant advantages for data center operational costs (OPEX) and cooling efficiency.

    Low latency: 200G NRZ excels in special application scenarios with stringent network latency requirements, such as high-frequency trading networks. The transmission method of NRZ signals provides an advantage in terms of latency.

    Deployment ease:

    Mature industry chain: The technology of 25G NRZ optical chips and components is relatively mature, providing a reliable foundation for the production of 200G NRZ. This makes the development of related 200G switch ports and optical module products relatively easy, facilitating rapid commercial deployment.

    Low-cost optical interconnection: Due to mature technology and industry chains, 200G NRZ achieves low-cost optical interconnection within data centers. This offers an economically effective solution for the construction and expansion of large-scale data centers.

    200G QSFP-DD SR8

    The 200G QSFP-DD SR8 is a multimode parallel product, utilizing an 8-channel 850nm VCSEL array, compliant with the 100GBASE-SR4 protocol standard. Leveraging the advantages of traditional VCSEL platforms, GIGALIGHT has adopted a simple, efficient, and reliable fiber coupling process. By introducing a 45° prism between the laser and the fiber, along with special material treatment on the fiber surface, the fiber coupling efficiency has been increased to over 80%.

    200G QSFP-DD PSM8

    The 200G QSFP-DD PSM8 is a high-speed product utilizing single-mode parallel technology. In comparison to wavelength division multiplexing (WDM) technology, PSM technology offers cost advantages. GIGALIGHT PSM optical module enables error-free long-distance transmission up to 10km, five times the distance achieved by traditional PSM optical modules.

    200G QSFP-DD LR8

    The 200G QSFP-DD LR8 optical module is based on an 8-channel LAN-WDM wavelength division multiplexing design, achieving a 1E-12 bit error rate over a transmission distance of 20km. In the context of high-reliability 5G middle-backhaul transmission systems, the long-term transmission of PAM4 signals may pose challenges such as insufficient bandwidth. The 200G QSFP-DD LR8, however, offers a high-performance, low-latency, and highly reliable channel solution.

    GIGALIGHT has recently made significant strides in optical design, particularly achieving notable success in the development of 800G optical modules. The design includes the completion of 800G SR8/DR8. For more details, please refer to here. Moreover, GIGALIGHT has successfully mass-produced and deployed 8-channel optical products in niche markets globally, encompassing various fields such as 200G, 400G, and 800G. Visit our official website for further information.

    9Jan, 2024
    200G: Where Bandwidth Meets Technological Evolution

    After the widespread use of 100G data centers, 200G and 400G data center technologies emerged. Overall, people hope that the per-bit cost of investing in 200G and 400G data centers will be on par with 100G. However, in reality, since different data center business models and transmission latency requirements exist, cost is just one mainstream consideration for customers. The primary focus is on meeting business needs with comprehensive cost-effectiveness. The industry is designing various 200G and 400G data center optical interconnect products based on different application demands.

    Two Different 200G Data Center Architectures have been developed.

    1. 200G 8x25G NRZ: Due to the prevalence of 25G NRZ in existing networks and the demand for low latency, the 8x25G NRZ architecture is suitable for achieving 200G data transmission.

    2. 200G 4x50G PAM4: The new network constructions without specific performance requirements, and equipment cost savings can be achieved by using PAM4 chipsets, enabling the application of PAM4 technology. Hence, the 4x50G PAM4 architecture is suitable for achieving 200G data transmission.

    The two different architectures of 200G Ethernet optical modules and their corresponding application scenarios are listed below.

    200G (8x25G NRZ):

    -200G QSFP-DD SR8 (Low latency, common in intra-rack interconnections and interconnections between TOR switches and server network cards).

    -200G QSFP-DD PSM8 (Low latency, interconnections between racks with an abundance of single-mode fibers).

    -200G QSFP-DD 2xCWDM4 (Low latency, interconnections between racks while significantly reducing the use of single-mode fibers).

    200G (4x50G PAM4):

    -200G QSFP56 SR4 (Common in intra-rack interconnections and interconnections between TOR switches and server network cards).

    -200G QSFP56 DR4 (Interconnections between racks with an abundance of single-mode fibers).

    -200G QSFP56 FR4 (Interconnections between racks while significantly reducing the use of single-mode fibers).

    What are the advantages of 200G compared to 100G?

    1. 200G (8x25G NRZ) VS 100G: The physical delay of 8x25G NRZ 200G optical modules is extremely low. It has twice the channels compared to 100G, resulting in approximately double the power consumption and slightly higher costs. However, customers are not only seeking lower prices but also overall cost-effectiveness, making 200G slightly advantageous.

    2. 200G (4x50G PAM4) VS 100G: Compared to 100G optical modules, 4x50G PAM4 provides 2x capacity on a single port while achieving cost-effectiveness (This has actually been achieved)

    What are the advantages of 200G compared to 400G?

    Compared to 400G data centers, 200G data centers require lower investments, have lower technical complexities and costs, and offer relatively higher cost-effectiveness. Although 400G provides higher transmission efficiency, its high deployment and maintenance costs and low localization rate limit its application.

    Thanks to breakthroughs in domestic manufacturers’ optical communication technology, the localization rate of 200G data centers has significantly increased. This reduces dependency on imports, enhances the independent controllability of data center technology in China, lowers the construction and operational costs of 200G data centers, and improves their cost-effectiveness.

    In summary, 200G data centers have their irreplaceable advantages. In terms of cost-effectiveness or the long-term, 200G data centers remain the superior choice. Their low power consumption and significant technological benefits are especially valuable for underdeveloped countries or enterprise-level data centers, making 200G the preferred option.

    200G PAM4 DML VS 200G PAM4 EML:

    To promote the development of economical data center technology, GIGALIGHT recently launched the 200G DR4/FR4 optical modules based on 200G PAM4 DML. How does this upgrade compare to the old version using EML?

    200G PAM4 DML and 200G PAM4 EML are primarily used for a distance of 2km, with 50G PAM4 DML achieving cost and power consumption advantages. The 50G PAM4 DML, providing cost and power consumption advantages compared to 50G PAM4 EML, requires a TEC temperature control circuit to maintain a constant operating temperature for the EA electro-absorption modulator. By contrast, 50G PAM4 DML eliminates the need for this, reducing design complexity, cost, and product power consumption.

    For example, the 200G QSFP56 FR4 DML version has a power consumption of 5W, making it more energy-efficient and cost-effective than the EML version.

    With the development of DML technology, especially in 50G PAM4 2km systems, the performance gap between DML and EML has decreased. With low-consumption, cost-effectiveness and simple manufacture, GIGALIGHT’s 50G PAM4 DML laser excels at applications in large-scale data centers while maintaining compatible metrics. The receiving OMA sensitivity and TDECQ (dB) indicators of the 200G QSFP56 FR4 DML version fully meet the protocol and the current application indicators of 200G FR4 2km transmission.

    As the leader of open optical network devices, GIGALIGHT advocates the vigorous development of economical data center technology. In order to implement this concept, we have launched a full range of 200G QSFP-DD and 200G QSFP56 data center optical transceiver products to further highlight the advantages of 200G in the field of economical data centers.

    26Dec, 2023
    Revolutionizing Data Centers: GIGALIGHT’s Advanced 800G Solutions Reshape Optical Connectivity for AI

    GIGALIGHT released a marketing report highlighting the imminent transformation in data center network architecture driven by the burgeoning adoption of AI applications recently. This shift has spurred investments in data center infrastructure, propelling growth in the 400G/800G optical module market.

    With the release of several 800G switch chips and the gradual deployment of 800G optical modules, the focus now lies in enabling data centers to seamlessly operate at this high 800G rate. This involves selecting the right optical components and cables while considering crucial factors such as bandwidth, distance, and cost.

    Given that AI heavily relies on parallel computing, the article proceeds to explore parallel wiring solutions for 800G data centers, specifically delving into DACs (Direct Attach Cables), AOCs (Active Optical Cables), and optical modules.

    800G Data Center DAC & AOC Solutions

    When it comes to ultra-short-distance applications, DACs and AOCs emerge as preferred choices. These modules directly link to cables, offering easy installation and cost efficiencies compared to optical module solutions. DACs, notably the most cost-effective, have shorter connection distances. Both DACs and AOCs are available in two variations: direct and breakout connections.

    Using DAC as an example, the maximum transmission distance is 2m (PCC)/5m (ACC), replaced by AOC extend up to 100m.

    800G Data Center Multimode Optical Module Solutions
    Multimode optical module connectivity mirrors AOC solutions, both capable of achieving connections up to 100m. The difference lies in the requirement for multimode optical modules to be paired with MPO multimode fibers.

    800G Data Center Single-mode Optical Module Solution
    For long-distance 800G data center setups, GIGALIGHT employs silicon photonics. Compared to conventional 8-lane EML-based 800G optical modules, silicon photonics modules require fewer lasers. For instance, the 800G DR8 utilizes just one laser to achieve lower power consumption without compromising performance. Besides the 500m reach of the 800G DR8 optical module, GIGALIGHT has also introduced the 800G DR8+ for 2km transmission and the 800G DR8++ for 10km transmission, available in OSFP and QSFP-DD packaging options.

    GIGALIGHT offers QSFP-DD packaging options for all the aforementioned solutions.

    The deployment of 800G data centers demands careful consideration of various cable types and their specific characteristics. Different 800G wiring solutions come with distinct advantages, and the choice should align with the specific requirements of the data center.

    Explore more interconnect architectures for AI applications at https://www.gigalight.com/news-events/reports-7329.html

    18Dec, 2023
    High-Speed Optical Module Demand Soars: AI Computing and Market Projections Drive Innovations

    Discovering the intersection of AI computing and escalating market trends, the reliance on optical modules has surged. From high-scale computational scenarios in AI-powered systems to market forecasts propelling technological advancements, the landscape is evolving. Let’s delve into the interplay of AI, market projections, and groundbreaking optical innovations, reshaping the future of computational networking

    Section 1, AI Computing Scenario Optical Module Application

    In the usage of NVIDIA’s A100 systems, such as within the NVIDIA DGX SuperPOD, concerning the application of optical modules required for computation and storage sides, all cables for both computation and storage sides utilize NVIDIA MF1S00-HxxxE series AOC active optical cables. Consequently, each port requires an optical module, meaning each cable corresponds to two optical modules. Therefore, the computation and storage sides total required amounts to (1120+1124+1120)*2 + (280+92+288)*2 = 8048 optical modules. In other words, the approximate quantity of 200G optical modules needed per GPU is about 1:7.2.

    DGX GH200 supercomputer, equipped with 256 NVIDIA GH200 Grace Hopper super chips, each of which can be regarded as a server, interconnected through NVLINK SWITCH. Structurally, the DGX GH200 adopts a two-tiered fat tree topology, with the first and second tiers employing 96 and 36 switches, respectively. Each NVLINK SWITCH has 32 ports operating at a speed of 800G. Additionally, the DGX GH200 is equipped with 24 NVIDIA Quantum-2 QM9700 IB switches for the IB network.

    For estimation based on ports, given the closer proximity of L1 tier, it’s assumed that copper cables are used for connectivity without involving optical modules. For the L2 tier with 36 switches in a non-converging fat tree architecture, each switch’s ports connect downwards to the uplink ports of L1 tier switches. Therefore, a total of 36 * 32 * 2 = 1152 units of 800G optical modules are needed. In the IB network architecture, the 24 switches require 24 * 32 = 768 units of 800G optical modules. Thus, the DGX GH200 supercomputer requires a total of 1152 + 768 = 1920 units of 800G optical modules, corresponding to 12 units of 800G optical modules per GH200 chip.

    Section 2, Optical Module Market Demand Forecast Driven by Computational Networking

    The significant surge in computing power demand driven by new-generation information technologies like cloud computing, artificial intelligence, and big data has hastened the development of cloud computing infrastructure. Concurrently, with the comprehensive launch of projects such as the “Eastern Data and Western Computing,” China’s computational infrastructure construction is rapidly advancing. Optical modules, as pivotal components in cloud computing data centers, will experience a continuous surge in market demand due to the substantial increase in data transmission volume.

    According to LightCounting’s projections, the global adoption rate of 800G technology is expected to be merely 0.62% by 2023. Large AI models like ChatGPT impose new demands on data flows within and outside data centers, potentially accelerating the transition of optical modules towards 800G. It’s anticipated that 800G optical modules will start dominating the market by the end of 2025.

    Based on LightCounting’s data, the global market size for optical modules increased from $58.6 billion in 2016 to $66.7 billion in 2020. Projections suggest that by 2025, the global optical module market will reach $11.3 billion, 1.7 times the size in 2020. Structurally, the data communication market is expected to hold around 60%, while the telecommunications market will encompass approximately 40% of the market share.

    GIGALIGHT Optical Modules for Computational Applications

    The core technology of GIGALIGHT’s silicon optical modules lies in its innovative packaging design with high-coupling efficiency in the free-space COB and the MZI software locking algorithm. Additionally, in terms of silicon waveguide cores, the company has engaged in collaborative design work for multiple silicon chip designs with partners.

    11Dec, 2023
    Cloud Storage: Transforming Data Management for Agility

    During the digital era, data is increasingly becoming the cornerstone asset for enterprises, experiencing exponential growth in volume. This surge in data has led to high costs for businesses using traditional storage technologies, prompting the emergence of a new approach to storage — cloud storage.

    Cloud storage involves enterprises and individuals leasing third-party storage space at a certain cost for data storage. Through network technology or distributed file systems, cloud storage aggregates various types of storage devices within the network through application software, collaboratively providing data storage and business access functions. Core technologies of cloud storage encompass virtualization, distributed storage, Software-Defined Storage (SDS), and Hyper-Converged Infrastructure (HCI) storage.

    Traditional storage technologies evolved to meet the demands of enterprise data centers, databases, enterprise applications, and virtualization integration. They fulfilled traditional enterprise application requirements for reliability, performance, capacity, and business continuity. However, in the face of cloud computing and the big data era, scalability and concurrent processing performance have become somewhat limited.

    Active suppliers globally offering traditional storage solutions include DELL-EMC, NetApp, HPE, Huawei, HDS, IBM, Fujitsu, and others.

    The emergence of technologies like big data, cloud computing, and virtualization has made traditional IT architectures inadequate to meet enterprise data storage needs. Hence, SDS and HCI infrastructures have emerged and expanded from small and medium-sized enterprises to large corporations.

    According to Fortune Business Insights, the global cloud storage market reached $702 billion in 2021. As the cost advantages of cloud storage solutions become more apparent, it will drive enterprises to further adopt cloud storage. The global cloud storage market is estimated to reach $834 billion in 2022, with an expected growth to $376.4 billion by 2029, at a compound annual growth rate of 24.0%.

    Moving forward, Software-Defined Storage (SDS), distributed storage, and Hyperconverged Infrastructure (HCI) will continue their upward trajectory, becoming pivotal for the future of cloud storage.

    Software-Defined Storage:

    Firstly, the significant trend in SDS development revolves around the application of flash memory. SDS development relies on hardware advancements, wherein the rapid progress of generic hardware lays the foundation for SDS ascension. Utilizing and optimizing flash memory assists SDS products in handling large-scale workloads for enterprise users. To meet the digital demands of enterprise users with lower costs and superior performance, SDS solution providers enhance product performance through continuous technological advancements, leveraging innovative storage technologies like NVMe-oF and 3D XPoint.

    Secondly, SDS will decouple storage system software and hardware. This allows generic hardware to replace proprietary hardware, reducing the threshold for storage system utilization. The rise of open-source frameworks accelerates the expansion of open SDS projects, with open-source initiatives like OpenStack and RedHat leading the way in open-source SDS development. In the control plane, applications like OpenSDS and OpenStack Cinder have matured. In the data plane, high-performance, highly reliable, and scalable open-source software like Ceph, GlusterFS, and Swift find extensive industry applications.

    Faced with new storage demands like massive unstructured data, traditional storage systems exhibit drawbacks of low flexibility, inadequate scalability, and high costs. Users are gradually inclining toward open-source distributed storage.

    Open-source SDS possesses several advantages:

    1. Driven by the open-source community, developers and contributors strive for innovation, technological implementation, and building solution ecosystems, actively promoting the development of open-source SDS technology.

    2. Enterprises can use enterprise-grade technology with higher quality, stability, and security compared to proprietary systems at lower costs.

    3. Open-source SDS decouples storage systems from hardware, allowing users to freely deploy storage platforms and flexibly expand storage devices. Utilizing proprietary storage systems binds users to a single vendor, whereas the use of open-source software enables users to freely choose vendors, realizing the true potential of software-defined storage.

    Distributed Storage:

    Distributed storage systems disperse data storage across multiple independent devices. Distributed network storage systems use a scalable system structure, utilizing multiple storage servers to share storage loads and location servers to locate storage information. It not only enhances system reliability, availability, and access efficiency but also facilitates scalability. Characteristics of distributed storage systems include:

    1. Scalability: Distributed storage systems can scale to clusters of several thousand servers, with the overall system performance growing linearly.

    2. Low cost: The automatic fault tolerance and load balancing features of distributed storage systems enable them to be constructed on low-cost servers. Additionally, linear scalability reduces server costs, enabling automatic operation and maintenance of distributed storage systems.

    3. High performance: Both for individual servers and the entire distributed storage cluster, distributed storage systems require high performance.

    Moreover, similar to how not all SDS is necessarily distributed, distributed storage systems are not always software-defined; they might be hardware-bound. For instance, IBM XIV storage, essentially a distributed storage, is delivered through dedicated hardware, thereby retaining hardware bindings and presenting high-cost issues.

    Hyper-Converged Infrastructure (HCI):

    Hyper-convergence refers to the process of integrating storage, computing, and network connection resources into a single IT framework system, aiming to reduce data center complexity and enhance scalability. This infrastructure amalgamates many advantages of Software-Defined Storage (SDS) and distributed storage. It represents a novel deployment architecture in a virtualized environment by internalizing external storage arrays within servers, sparking an industry shift that profoundly influences the existing IT landscape. Embracing the “hyper-converged architecture” is envisioned as a rational mode for deploying fundamental systems. The hyper-converged architecture is more encompassing than the mere software-defined storage hierarchy, as it covers a wider spectrum and to some extent encapsulates software-defined storage.

    However, hyper-convergence is still in a developmental phase. Despite rapid market expansion, the involvement of numerous vendors and the absence of standardized hyper-converged products pose challenges. Many products currently in the market are relatively new and necessitate continual iterations to enhance stability and sustainability.

    The diverse needs of hyper-converged customers range from requiring substantial storage capacities to necessitating high-computing systems. Yet, existing hyper-converged products often remain too singular and fail to meet the needs of all customers. Moreover, integrating hyper-converged systems with traditional legacy devices poses challenges, with issues concerning the seamless integration of old and new systems remaining a critical concern.

    Conclusion

    The versatility of cloud storage has opened a new chapter in providing organizations with more efficient, scalable, and adaptable data management solutions. The continued evolution of cloud storage is not just a technological shift, it is a transformative force that is propelling organizations into a more agile and competitive future in a data-driven era.

    15Nov, 2023
    Emerging Packaging Technologies: A Technical Deep Dive

    Advanced packaging stands out as a major highlight in the ‘More than Moore’ era. As chip miniaturization becomes increasingly challenging and costly at each process node, engineers are opting to place multiple chips into advanced packaging rather than struggle to further shrink the chips.

    3D packaging

    In 2.5D packaging, bare die stacks or side-by-side placements rest atop an interposer with silicon vias (TSVs). The base, or the interposer, provides connectivity between chips. In 3D IC packaging, logic die stacks together or with memory die stacks without constructing a large System on Chip (SoC). Connections between bare dies occur through an active interposer, while in 2.5D IC packaging, components are stacked on the interposer using conductive bumps or TSVs. On the other hand, 3D IC packaging connects multiple layers of silicon wafers using TSV-enabled components.

    Chiplet packaging

    A series of modular chips in a chip library can be integrated into packaging using die-to-die interconnect technology. Chiplets represent another form of 3D IC packaging, enabling the heterogeneous integration of CMOS and non-CMOS components. In essence, they are smaller System on Chips (SoCs) or chiplets rather than large SoCs in the package. Breaking down large SoCs into smaller chips boasts higher yields and lower costs compared to a single bare die. Chiplets empower designers to leverage various IPs without concern for process nodes or manufacturing technologies. They can use diverse materials, including silicon, glass, and laminates, in chip fabrication.

    Fan-out (FO) packaging

    In FO packaging, connections fan out across the chip surface, providing more external I/O. It embeds bare dies entirely in epoxy molding compound (EMC), eliminating process flows like wafer bumps, underfill, flip chips, cleaning, underfill spraying, and curing, thus bypassing the need for an interposer, simplifying heterogeneous integration. Compared to other packaging types, FO technology offers smaller packages with more I/O. In 2016, it enabled Apple to integrate TSMC’s packaging technology, housing its 16nm application processor and mobile DRAM into one package for the iPhone 7, becoming a technological standout.

    Fan-out wafer-level packaging (FOWLP)

    This technology is an enhancement of wafer-level packaging (WLP), offering more external connections for silicon chips. It embeds chips into EMC, constructs a high-density redistribution layer (RDL) on the wafer surface, and applies solder balls, forming a reconstituted wafer. Typically, treated wafers are first cut into individual bare dies, then dispersed on a carrier structure, and the gaps are filled to form a reconstituted wafer. FOWLP provides numerous connections between the package and the application circuit board, and due to the larger substrate than bare dies, the spacing between the dies is, in fact, more lenient.

    1Nov, 2023
    Emerging Trends in 400G and 800G: Low-Power Solutions for High-Speed Networks

    As Serdes technology drives data centers into the era of 400G and 800G, port power consumption has become a hot topic in the industry. Low-power 400G/800G interconnection solutions have been successively introduced, attracting wide attention in the industry and being widely regarded as a key technology for AI and machine learning in smart data centers.

    1. CPO Aims to Address Next-Generation Bandwidth and Power Challenges

    With the continuous acceleration of bandwidth in network and computing structures, innovation is required in system and chip architecture to mitigate the slowdown of Moore’s Law. Meanwhile, copper interconnects are rapidly reaching their bandwidth distance limits. Silicon photonics is crucial for sustaining rapid data growth and high-bandwidth applications. Co-Packaged Optics (CPO) involves co-packaging switch chip ASICs and optoelectronic engines (optical transceivers) on the same substrate, with the optical engines placed as close to the ASIC as possible to minimize high-speed electrical channel losses and impedance discontinuities. This enables the use of faster, lower-power off-chip I/O drivers. Using CPO not only achieves networking but also facilitates GPU-to-GPU interconnects, resource pooling, and memory disaggregation. It meets the requirements of AI/ML training clusters with high bandwidth and radix connections, the lowest per-bit cost, and the highest power efficiency.

    2. Linear Direct-Drive Pluggable Modules Also Reduce Power Consumption

    In the era of 400G and 800G, in addition to pluggable optical modules and CPO solutions, Linear Direct Drive (also known as linear drive) pluggable 400G/800G optical modules became a research hotspot at OFC in March of this year. The biggest advantage of this optical module solution is that it eliminates the need for DSP chips, significantly reducing the power consumption and latency of signal processing at the module level.

    GPU servers serving applications such as AI and machine learning provide excellent computing power but also result in increased server power consumption. The high-speed interconnection of 400G/800G leads to a corresponding increase in the power consumption of optical modules and network equipment. Both CPO and linear direct-drive pluggable modules may be interconnection solutions for future smart data centers, providing the lowest system-level power by eliminating all possible active components from the interconnect.

    13Oct, 2023
    GIGALIGHT Satisfactorily Delivers DCI 2.0 BOX and 400G QSFP-DD ZR+ Modules Overseas Clients

    SHENZHEN, China Oct. 13, 2023 — GIGALIGHT, through its Open Optical Network Lab, is excited to announce the successful deployment of single-lambda 400G DCI BOX network systems for international data center and telecommunications operator clients. This cutting-edge system leverages the latest 400G QSFP DD ZR/ZR+ coherent optical modules and is housed in a 2U chassis, offering a remarkable maximum transmission capacity of 6.4T. This innovative solution is built around a white box design.

    Key System Features:

    Capacity and Form Factor

    • A 2U standalone chassis can support a maximum capacity of 6.4T, with options for 1U and 2U chassis.

    Use Cases

    • Primarily designed for Data Center Interconnect (DCI) and metro network WDM/backbone WDM, providing a white box transmission platform.

    Design Advantages:

    • The product emphasizes white box design and simplified architecture.
    • A hybrid design of optical and electrical layers effectively saves data center space and facilitates bandwidth expansion.
    • Supports SNMP-based graphical management interface for intuitive fault localization.

    Cooling and Redundancy

    • Utilizes a front-to-rear airflow design, combined with multiple sets of high-speed redundant fans and power supplies, ensuring outstanding cooling performance.

    Hardware Support

    • Optical Layer: Supports Raman, EDFA, WSS, and OP cards, among others.
    • Electrical Layer: Line-side supports 100G/200G/400G coherent cards, while client-side supports 10GE/25GE/100GE/400GE.

    Network Management

    • Supports SNMP/Netconf protocols, CLI/Web/BS management, dual main control backup, and OSC communication.
    • Boasts robust transmission and network management capabilities, making it especially suitable for data center DCI and metropolitan network applications.

    Business Cards

    400G QSFP-DD DCO Muxponder

    This is the first business card introduced by GIGALIGHT in China. The line-side port supports cost-effective 400G QSFP-DD DCO ZR/ZR+, while the customer side supports 4x100GE QSFP28 ports, meeting the needs of DCI interconnect scenario applications.

    800G Transponder 1/4 Business Card

    With up to 800G Bandwidth, featuring support for two 400G CFP2 DCO on the line side and 2x400G QSFP-DD ports on the customer side, catering to high-bandwidth DCI applications.

    400G QSFP-DD DCO ZR+ Coherent Module

    Supports single-wavelength 400G DWDM, adjustable Tx optical power from 0 to -6dBm, flexible grid, and openZR+ protocol. It utilizes OFEC, offers excellent interoperability, achieves an Rx OSNR of 24dB/0.1nm @ 400G 16QAM, meets the requirements for 300km to 400km service interconnections, and has a typical power consumption of less than 22W.

    GIGALIGHT is one of the OpenZR+ members. The company boasts significant technical expertise in the coherent optical module field. GIGALIGHT’s Open Optical Network Lab has conducted comprehensive integration and fundamental research on OpenDCI BOX. Since entering the coherent wavelength division transmission system business, GIGALIGHT has successfully implemented network and transmission services based on 200G and 400G coherent optical modules for several overseas customers. This has led to the accumulation of extensive experience in overseas customer installation and maintenance

    About GIGALIGHT

    As an open optical networking explorer, Gigalight integrates the design, manufacturing, and sales of both active and passive optical devices and subsystems. The company’s product portfolio includes optical modules, silicon photonics modules, liquid-cooled modules, passive optical components, active optical cables, direct attach copper cables, coherent optical communication modules, and OPEN DCI BOX subsystems. Gigalight focuses on serving applications such as data centers, 5G transport networks, metropolitan WDM transmission, ultra-HD broadcast and video, and more. It stands as an innovative designer of high-speed optical interconnect hardware solutions.

    27Sep, 2023
    What is the Bit Error Rate(BER)?

    The Bit Error Rate (BER) is a metric used to measure the rate of bit transmission errors in digital communication systems. It represents the ratio of the number of erroneous bits received during transmission over a certain period to the total number of bits received during the same time. It is typically expressed as a percentage or in exponential form, for example, 1E-6 indicates one error bit in every one million transmitted bits.

    The BER directly relates to the reliability and performance of digital communication systems. A lower BER signifies more reliable transmission, while a higher BER indicates poorer transmission quality, potentially leading to data loss or transmission errors.

    In digital communication systems, BER can be measured by sending a known bit sequence and then comparing the received bit sequence with the transmitted one at the receiving end. By counting the number of error bits, the BER can be calculated.

    The target value for BER often depends on specific application scenarios and system requirements. In high-speed optical fiber communication systems, a very low BER is typically required, such as 1E-12 or lower. In certain wireless communication systems, a higher BER may be tolerated, such as 1E-5.

    To reduce BER, digital communication systems often employ a range of techniques and methods, including channel coding, modulation, equalization, and error correction. These technologies enhance signal robustness and fault tolerance, thereby reducing the transmission error rate.

    Several factors influence the Bit Error Rate (BER), including:

    1. Channel Noise: Channel noise refers to random noise introduced during signal transmission. Higher levels of noise lead to higher BER.

    2. Signal Power: Lower signal power results in greater susceptibility to noise, leading to higher BER.

    3. Transmission Distance: Longer transmission distances increase signal attenuation and distortion, contributing to a higher BER.

    4. Signal Modulation Scheme: Different modulation schemes exhibit varying noise resistance. Some schemes (e.g., QAM) have lower BER in high signal-to-noise conditions, while others (e.g., ASK) may perform better in low signal-to-noise conditions.

    5. Channel Distortion: Channel distortion includes multipath effects, frequency-selective fading, and phase offsets. These distortions introduce interference and errors, leading to higher BER.

    6. Intersymbol Interference: Intersymbol interference refers to mutual interference between adjacent bits. Higher intersymbol interference leads to a higher BER.

    7. Signal Modulation Rate: Higher modulation rates imply shorter bit durations, imposing stricter requirements on the transmission channel, potentially resulting in higher BER.

    8. Data Rate: Higher data rates may increase interference between bits, leading to higher BER.

    9. System Design and Implementation: Factors such as system design and implementation quality, error correction, and detection mechanisms also influence BER.

    In conclusion, Bit Error Rate (BER) is influenced by multiple factors, including channel noise, signal power, transmission distance, signal modulation scheme, channel distortion, intersymbol interference, signal modulation rate, data rate, and system design and implementation. In practical applications, these factors need to be carefully considered, and appropriate technical means should be employed to minimize BER.