Things You Must Know: 200G vs. 400G Ethernet in Data Centers

With the rise of high data rate applications such as 5G and cloud computing, 200G and 400G Ethernet are getting much attention in data centers. In most cases, 400G Ethernet is more competitive than 200G Ethernet with regards to the applications in data centers. In this post, we are about to reveal how 400G Ethernet outperforms 200G Ethernet in several aspects.

400G Ethernet vs 200G Ethernet: More Comprehensive Standardization

During the evolution of the IEEE protocol standard, the 200G standard was issued later than the 400G standard. The 400G standard was first proposed in 2013 by IEEE 802.3 Working Group and was approved in 2017 with IEEE 802.3bs 400G Ethernet standard. While the 200G standard was proposed and approved in 2015 and 2018 respectively. And the 200G single-mode specification is generally based on the 400G single-mode specification but halved the 400G one. With the fast upgrades of 400G technology and its products due to market needs, the 400G standard is more comprehensive and maturer than that of 200G.

Common Use of 100G Server Promotes More 400G Ethernet Applications

Network switch speed is always driven by server uplink speed. No matter in the past or at present, one-to-four structure is often used to connect switches and servers to increase the port density of switches. And this structure is likely to be adopted in the future as well. Then, how to choose between the 200G Ethernet and 400G Ethernet mainly depends on the server we use.

How to Connect Servers in Data Centers.jpg

According to Crehan research and forecast, the momentum of 100G servers surpassed that of 50G servers since 2020. That means, most network operators are likely to use 100G server connection rather than 50G. And 100G servers would become the mainstream according to the trends during 2020-2023. In other words, one could skip 200G and choose 400G directly with 100G server deployed.

50G vs 100G Server Adoption Rates.jpg

Optical Transceiver Market Drives 400G Ethernet

There are two main factors that push 400G Ethernet more popular than 200G Ethernet in the optical transceiver market. One is the module supply, another is the cost.

400G Optical Transceivers Gain More Market Supplies and Acceptance

Normally, the early adoption of 400G is to support the rise of 200G long-haul for aggressive DCI network builds. It makes 400G possible in metro networks and supports 3x the distance for 200G wavelengths. WIth further development, 400G transceivers are more favorable among manufacturers. Many suppliers pay more attention to 400G Ethernet rather than 200G. For example, Senko’s new CS connector is specifically designed for 400G data center optimization. Actually, all things have reasons. Even if the total cost of 200G transceiver and 400G transceiver is the same, the cost and power consumption per bit of 400G transceiver is half of the 200G’s because of the doubled bandwidth of 400G. More importantly, the total revenue data among 100G, 200G and 400G shows that 400G is far beyond 200G in the whole market.

Total Revenue for 100G 200G and 400G Transceivers.jpg

According to shipment data of the top 8 suppliers gathered by Omdia, the 400G transceiver market is more prosperous than that of 200G. There are more options for users in 400G deployment. Although the top 8 suppliers all provide 200G and 400G transceivers, 200G transceivers only offer 100m SR4 and 2km FR4 while 400G transceivers could offer more options like SR8 100mDR4 500mFR4 2kmLR4 10km, and ER8 40km, etc. In addition, 400G products, such as 400G DAC and 400G DAC breakout cables and solutions are maturer and more perfect than 200G because of their earlier release.

Supplier SupportFinisarInnolightFITLumentumAccelinkSource PhotonicsAOIHisense
200G SR4      
200G FR4    
400G SR8
400G SR4.2     
400G DR4
400G FR4
400G ZR       

400G Optical Modules Support More Applications With Fewer Cost

Compared to 200G transceivers, 400G transceivers could support more applications including DCI and 200G applications. And they can double the traffic carrying capacity between applications than 100G/200G solutions. With 400G solutions, fewer transponders will be needed, resulting in less transportation and operating costs. This will make the 400G market more lively in return.

400G Ethernet Is more Suitable for Future Network Upgrades

The 200G optical modules will include two main form factors, namely QSFP-DD and CFP2. The 400G optical transceivers will mainly include QSFP-DD and OSFP packages. Since the OSFP is expected to offer a better path to 800G and higher transmission rates, 400G transceiver is more suitable and convenient for future network migration.

Conclusion

From the current analysis and evidence above, 400G Ethernet is more competitive than 200G Ethernet in Ethernet standardization, 100G server connection, optical transceiver market and future network upgrades. There is no need to hesitate between 200G Ethernet and 400G Ethernet. Choosing 400G Ethernet and products is a wise decision not only for the current but for the long-term future.

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https://community.fs.com/blog/200g-vs-400g-ethernet.html

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How Is 5G Pushing the 400G Network Transformation?

With the rapid technological disruption and the wholesale shift to digital, several organizations are now adopting 5G networks, thanks to the fast data transfer speeds and improved network reliability. The improved connectivity also means businesses can expand on their service delivery and even enhance user experiences, increasing market competitiveness and revenue generated.

Before we look at how 5G is driving the adoption of 400G transformation, let’s first understand what 5G and 400G are and how the two are related.

What is 5G?

5G is the latest wireless technology that delivers multi-Gbps peak data speeds and ultra-low latency. This technology marks a massive shift in communication with the potential to greatly transform how data is received and transferred. The increased reliability and a more consistent user experience also enable an array of new applications and use cases extending beyond network computing to include distributed computing.

And while the future of 5G is still being written, it’s already creating a wealth of opportunities for growth & innovation across industries. The fact that tech is constantly evolving and that no one knows exactly what will happen next is perhaps the fascinating aspect of 5G and its use cases. Whatever the future holds, one is likely certain: 5G will provide far more than just a speedier internet connection. It has the potential to disrupt businesses and change how customers engage and interact with products and services.

What is 400G?

400G or 400G Ethernet is the next generation of cloud infrastructure that offers a four-fold jump in max data-transfer speed from the standard maximum of 100G. This technology addresses the tremendous bandwidth demands on network infrastructure providers, partly due to the massive adoption of digital transformation initiatives.

Additionally, exponential data traffic growth driven by cloud storage, AI, and Machine Learning use cases has seen 400G become a key competitive advantage in the networking and communication world. Major data centers are also shifting to quicker, more scalable infrastructures to keep up with the ever-growing number of users, devices, and applications. Hence high-capacity connection is becoming quite critical.

How are 5G and 400G Related?

The 5G wireless technology, by default, offers greater speeds, reduced latencies, and increased data connection density. This makes it an attractive option for highly-demanding applications such as industrial IoT, smart cities, autonomous vehicles, VR, and AR. And while the 5G standard is theoretically powerful, its real-world use cases are only as good as the network architecture this wireless technology relies on.

The low-latency connections required between devices, data centers, and the cloud demands a reliable and scalable implementation of the edge-computing paradigms. This extends further to demand greater fiber densification at the edge and substantially higher data rates on the existing fiber networks. Luckily, 400G fills these networking gaps, allowing carriers, multiple-system operators (MSOs), and data center operators to streamline their operations to meet most of the 5G demands.

5G Use Cases Accelerating 400G transformation

As the demand for data-intensive services increases, organizations are beginning to see some business sense in investing in 5G and 400G technologies. Here are some of the major 5G applications driving 400G transformation.

High-Speed Video Streaming

The rapid adoption of 5G technology is expected to take the over-the-top viewing experience to a whole new level as demand for buffer-free video streaming, and high-quality content grows. Because video consumes the majority of mobile internet capacity today, the improved connectivity will give new opportunities for digital streaming companies. Video-on-demand (VOD) enthusiasts will also bid farewell to video buffering, thanks to the 5G network’s ultra-fast download speeds and super-low latency. Still, 400G Ethernet is required to ensure reliable power, efficiency, and density to support these applications.

Virtual Gaming

5G promises a more captivating future for gamers. The network’s speed enhances high-definition live streaming, and thanks to ultra-low latency, 5G gaming won’t be limited to high-end devices with a lot of processing power. In other words, high-graphics games can be displayed and controlled by a mobile device; however, processing, retrieval, and storage can all be done in the cloud.

Use cases such as low-latency Virtual Reality (VR) apps, which rely on fast feedback and near-real-time response times to give a more realistic experience, also benefit greatly from 5G. And as this wireless network becomes the standard, the quantity and sophistication of these applications are expected to peak. That is where 400G data centers and capabilities will play a critical role.

The Internet of Things (IoT)

Over the years, IoT has grown and become widely adopted across industries, from manufacturing and production to security and smart home deployments. Today, 5G and IoT are poised to allow applications that would have been unthinkable a few years ago. And while this ultra-fast wireless technology promises low latency and high network capacity to overcome the most significant barriers to IoT proliferation, the network infrastructure these applications rely on is a key determining factor. Taking 5G and IoT to the next level means solving the massive bandwidth demands while delivering high-end flexibility that gives devices near real-time ability to sense and respond.

400G Network

400G Ethernet as a Gateway to High-end Optical Networks

Continuous technological improvements and the increasing amount of data generated call for solid network infrastructures that support fast, reliable, and efficient data transfer and communication. Not long ago, 100G and 200G were considered sophisticated network upgrades, and things are getting even better.

Today, operators and service providers that were among the first to deploy 400G are already reaping big from their investments. Perhaps one of the most compelling features of 400G isn’t what it offers at the moment but rather its ability to accommodate further upgrades to 800G and beyond. What’s your take on 5G and 400G, or your progress in deploying these novel technologies?

Article Source: How Is 5G Pushing the 400G Network Transformation?

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How 400G Has Transformed Data Centers

With the rapid technological adoption witnessed in various industries across the world, data centers are adapting on the fly to keep up with the rising client expectations. History is also pointing to a data center evolution characterized by an ever-increasing change in fiber density, bandwidth, and lane speeds.

Data centers are shifting from 100G to 400G technologies in a bid to create more powerful networks that offer enhanced experiences to clients. Some of the factors pushing for 400G deployments include recent advancements in disruptive technologies such as AI, 5G, and cloud computing.

Today, forward-looking data centers that want to maximize cost while ensuring high-end compatibility and convenience have made 400G Ethernet a priority. Below, we have discussed the evolution of data centers, the popular 400G form factors, and what to expect in the data center switching market as technology continues to improve.

Evolution of Data Centers

The concept of data centers dates back to the 1940s, when the world’s first programmable computer, the Electronic Numerical Integrator and Computer, or ENIAC, was the apex of computational technology. The latter was primarily used by the US army to compute artillery fire during the Second World War. It was complex to maintain and operate and was only operated in a particular environment.

This saw the development of the first data centers centered on intelligence and secrecy. Ideally, a data center would have a single door and no windows. And besides the hundreds of feet of wiring and vacuum tubes, huge vents and fans were required for cooling. Refer to our data center evolution infographic to learn more about the rise of modern data centers and how technology has played a huge role in shaping the end-user experience.data center evolution

The Limits of Ordinary Data Centers

Some of the notable players driving the data center evolution are CPU design companies like Intel and AMD. The two have been advancing processor technologies, and both boost exceptional features that can support any workload.

And while most of these data center processors are reliable and optimized for several applications, they aren’t engineered for the specialized workloads that are coming up like big data analytics, machine learning, and artificial intelligence.

How 400G Has Transformed Data Centers

The move to 400 Gbps drastically transforms how data centers and data center interconnect (DCI) networks are engineered and built. This shift to 400G connections is more of a speculative and highly-dynamic game between the client and networking side.

Currently, two multisource agreements compete for the top spot as a form-factor of choice among consumers in the rapidly evolving 400G market. The two technologies are QSFP-DD and OSFP optical/pluggable transceivers.

OSFP vs. QSFP-DD

QSFP-DD is the most preferred 400G optical form factor on the client-side, thanks to the various reach options available. The emergence of the Optical Internetworking Forum’s 400ZR and the trend toward combining switching and transmission in one box are the two factors driving the network side. Here, the choice of form factors narrows down to power and mechanics.

The OSFP being a bigger module, provides lots of useful space for DWDM components, plus it features heat dissipation capabilities up to 15W of power. When putting coherent capabilities into a small form factor, power is critical. This gives OSFP a competitive advantage on the network side.

And despite the OSFP’s power, space, and enhanced signal integrity performance, it’s not compatible with QSFP28 plugs. Additionally, its technology doesn’t have the 100Gbps version, so it cannot provide an efficient transition from legacy modules. This is another reason it has not been widely adopted on the client side.

However, the QSFP-DD is compatible with QSFP28 and QSFP plugs and has seen a lot of support in the market. The only challenge is its low power dissipation, often capped at 12 W. This makes it challenging to efficiently handle a coherent ASIC (application-specific integrated circuit) and keep it cool for an extended period.

The switch to 400GE data centers is also fueled by the server’s adoption of 25GE/50GE interfaces to meet the ever-growing demand for high-speed storage access and a vast amount of data processing.OSFP vs. QSFP-DD

The Future of 400G Data Center Switches

Cloud service provider companies such as Amazon, Facebook, and Microsoft are still deploying 100G to reduce costs. According to a report by Dell’Oro Group, 100G is expected to peak in the next two years. But despite 100G dominating the market now, 400G shipments are expected to surpass 15M million switch ports by 2023.

In 2018, the first batch of 400G switch systems based on 12.8 Tbps chips was released. Google, which then was the only cloud service provider, was among the earliest companies to get into the market. Fast-forward, other cloud service providers have entered the market helping fuel the transformation even further. Today, cloud service companies make a big chunk of 400G customers, but service providers are expected to be next in line.

Choosing a Data Center Switch

Data center switches are available in a range of form factors, designs, and switching capabilities. Depending on your unique use cases, you want to choose a reliable data center switch that provides high-end flexibility and is built for the environment in which they are deployed. Some of the critical factors to consider during the selection process are infrastructure scalability and ease of programmability. A good data center switch is power efficient with reliable cooling and should allow for easy customization and integration with automated tools and systems. Here is an article about Data Center Switch Wiki, Usage and Buying Tips.

Article Source: How 400G Has Transformed Data Centers

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400ZR: Enable 400G for Next-Generation DCI

400ZR: Enable 400G for Next-Generation DCI

To cope with large-scale cloud services and other growing data center storage and processing needs, the data center systems have become increasingly decentralized and difficult to manage. And applications like artificial intelligence (AI) urgently need low-latency, high-bandwidth network architectures to support the large number of machine-to-machine input/output (I/O) generated between servers. To ensure the basic performance of these applications, the maximum fiber propagation between these distributed data centers must be limited to about 100 km. Therefore, these data centers must be connected in distributed clusters. In order to ensure high-bandwidth and high-density data center interconnection at the same time, 400G ZR came into being. In this post, we will reveal what 400ZR is, how it works and the influences it brings about.

What Is 400ZR?

400ZR, or 400G ZR, is a standard that will enable the transmission of multiple 400GE payloads over Data Center Interconnect (DCI) links up to 80 km using dense wavelength division multiplexing (DWDM) and higher-order modulation. It aims to ensure an affordable and long-term implementation based on single-carrier 400G using dual-polarization 16 QAM (16-state quadrature amplitude modulation) at approximately 60 gigabaud (Gbaud). Developed by Optical Interconnect Forum (OIF), the 400ZR project is essential to facilitate the reduction of the cost and complexity of high-bandwidth data center interconnects and to promote interoperability among optical module manufacturers.

400G ZR

Figure 1: 400G ZR Transceiver in DCI Switch or Router

How Does 400ZR Work?

400G ZR proposes a technology-driven solution for high-capacity data transmission, which could be matched with the 400GE switch port. It uses a unique design of advanced coherent optical technology for small, pluggable form factor modules. Although the product form factor is not specified in the IA (implementation agreement), the companies or groups contributing to the 400ZR have defined this specification to fit the solution. These form factors defined separately by Multi-Source Agreement (MSA) bodies specify compact mechanical transceivers like QSFP-DD and OSFP, which are connectorized and pluggable into a compatible socket in a system platform. That is to say, the compatible 400ZR solutions that come to market will also be interoperable since the OIF and form factor MSAs are industry-wide organizations. And the interoperability of the 400ZR solutions offers the dual benefit of simplified supply chain management and deployment.

400ZR+ for Longer-reach Optical Transmission

Like other 400G transceivers, the pluggable coherent 400ZR solution can support 400G Ethernet interconnection and multi-vendor interoperability. However, it is not suitable for next-generation metro-regional networks that need transmission over 80 km with a line capacity of 400 Gb/s. Under such circumstances, 400ZR+, or 400G ZR+ is proposed. The 400ZR+ is expected to further enhance modularity by supporting multiple different channel capacities based on coverage requirements and compatibility with installed metro optical infrastructure. With 400ZR+, both the transmission distance and line capacity could be assured.

What Influences Will 400ZR Bring About?

Although 400ZR technology is still in its infancy, once it is rolled out, it will have a significant impact on many industries as the following three: hyper-scale data centers, distributed campuses & metropolitan areas and telecommunications providers.

400ZR Helps Cloud and Hyperscale Data Centers Adapt to the Growing Demand for Higher Bandwidth

The development of DCI and 400ZR could help cloud and hyper-scale data centers adapt to the growing demand for higher bandwidth on the network. They could deal with the exponential growth of applications such as cloud services, IoT devices, and streaming video. As time goes by, 400G ZR will contribute more to the ever-growing applications and users for the whole networking.

400ZR Will Support Interconnects in Distributed Data Centers

As is mentioned above, 400ZR technology will support the necessary high-bandwidth interconnects to connect distributed data centers. With this connection, distributed data centers can communicate with each other, share data, balance workloads, provide backup, and expand data center capacity when needed.

400ZR Allows Telecommunications Companies to Backhaul Residential Traffic

400G ZR standard will allow telecommunications companies to backhaul residential traffic. When running at 200 Gb/s using 64 Gbaud signalings and QPSK modulation, 400ZR can increase the range of high loss spans. For 5G networks, 400G ZR provides mobile backhaul by aggregating multiple 25 Gb/s streams. 400ZR helps promote emerging 5G applications and markets.

400ZR+/400ZR- Will Provide Greater Convenience Based on 400ZR

In addition to the interoperable 400G mode, the 400ZR transceiver is also expected to support other modes to increase the range of addressable applications. These modes are called 400ZR + and 400ZR-. “+” indicates that the power consumption of the module exceeds the 15W required by IA and some pluggable devices, enabling the module to use more powerful signal processing technology to transmit over distances of hundreds of kilometers. “-” indicates that the module supports low-speed modes, such as 300G, 200G, and 100G, which provide network operators with more flexibility.

Will 400ZR Stay Popular In the Next Few Years?

According to the data source below from LightCounting, 400ZR will lead the growth of optical module sales in 2021-2024. The figure below shows the shipment data of high-speed (100G and above) and low-speed (10G and below) DWDM modules sold on the market. It is clear that modules used in Cloud or DCI have an increasing tendency in 2021-2024. That means 400ZR will lead annual growth from 2021.

Source

In addition, with the first 100Gbps SerDes implementation in switching chips expected in 2021, the necessary data rate will move to 800 Gbps within the next 1-2 years for the optics interface. Since the OSFP form factor has been defined to allow an 8x 100GE interface without changing the definition of the transceiver. Similarly, in parallel, the coherent optics on the line side will transition to support 128GBaud 16QAM within a similar time frame, making it easy to migrate from the current 400ZR to the next-generation 800ZR. Therefore, 400ZR is crucial no matter in the current or the future network development.

Article Source

https://community.fs.com/blog/400zr-enable-400g-for-next-generation-dci.html

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400G Data Center Deployment Challenges and Solutions

As technology advances, specific industry applications such as video streaming, AI, and data analytics are increasingly pushing for increased data speeds and massive bandwidth demands. 400G technology, with its next-gen optical transceivers, brings a new user experience with innovative services that allow for faster and more data processing at a time.

Large data centers and enterprises struggling with data traffic issues embrace 400G solutions to improve operational workflows and ensure better economics. Below is a quick overview of the rise of 400G, the challenges of deploying this technology, and the possible solutions.

The Rise of 400G Data Centers

The rapid transition to 400G in several data centers is changing how networks are designed and built. Some of the key drivers of this next-gen technology are cloud computing, video streaming, AI, and 5G, which have driven the demand for high-speed, high-bandwidth, and highly scalable solutions. The large amount of data generated by smart devices, the Internet of Things, social media, and other As-a-Service models are also accelerating this 400G transformation.

The major benefits of upgrading to a 400G data center are the increased data capacity and network capabilities required for high-end deployments. This technology also delivers more power, efficiency, speed, and cost savings. A single 400G port is considerably cheaper than four individual 100G ports. Similarly, the increased data speeds allow for convenient scale-up and scale-out by providing high-density, reliable, and low-cost-per-bit deployments.

How 400G Works

Before we look at the deployment challenges and solutions, let’s first understand how 400G works. First, the actual line rate or data transmission speed of a 400G Ethernet link is 425 Gbps. The extra 25 bits establish a forward error connection (FEC) procedure, which detects and corrects transmission errors.

400G adopts the 4-level pulse amplitude modulation (PAM4) to combine higher signal and baud rates. This increases the data rates four-fold over the current Non-Return to Zero (NRZ) signaling. With PAM4, operators can implement four lanes of 100G or eight lanes of 50G for different form factors (i.e., OSFP and QSFP-DD). This optical transceiver architecture supports transmission of up to 400 Gbit/s over either parallel fibers or multiwavelength.

PM4
PAM4

Deployment Challenges & Solutions

Interoperability Between Devices

The PAM4 signaling introduced with 400G deployments creates interoperability issues between the 400G ports and legacy networking gear. That is, the existing NRZ switch ports and transceivers aren’t interoperable with PAM4. This challenge is widely experienced when deploying network breakout connections between servers, storage, and other appliances in the network.

400G transceiver transmits and receives with 4 lanes of 100G or 8 lanes of 50G with PAM4 signaling on both the electrical and optical interfaces. However, the legacy 100G transceivers are designed on 4 lanes of 25G NRZ signaling on the electrical and optical sides. These two are simply not interoperable and call for a transceiver-based solution.

One such solution is the 100G transceivers that support 100G PAM4 on the optical side and 4X25G NRZ on the electrical side. This transceiver performs the re-timing between the NRZ and PAM4 modulation within the transceiver gearbox. Examples of these transceivers are the QSFP28 DR and FR, which are fully interoperable with legacy 100G network gear, and QSFP-DD DR4 & DR4+ breakout transceivers. The latter are parallel series modules that accept an MPO-12 connector with breakouts to LC connectors to interface FR or DR transceivers.

NRZ & PM4
Interoperability Between Devices

Excessive Link Flaps

Link flaps are faults that occur during data transmission due to a series of errors or failures on the optical connection. When this occurs, both transceivers must perform auto-negotiation and link training (AN-LT) before data can flow again. If link flaps frequently occur, i.e., several times per minute, it can negatively affect throughput.

And while link flaps are rare with mature optical technologies, they still occur and are often caused by configuration errors, a bad cable, or defective transceivers. With 400GbE, link flaps may occur due to heat and design issues with transceiver modules or switches. Properly selecting transceivers, switches, and cables can help solve this link flaps problem.

Transceiver Reliability

Some optical transceiver manufacturers face challenges staying within the devices’ power budget. This results in heat issues, which causes fiber alignment challenges, packet loss, and optical distortions. Transceiver reliability problems often occur when old QSFP transceiver form factors designed for 40GbE are used at 400GbE.

Similar challenges are also witnessed with newer modules used in 400GbE systems, such as the QSFP-DD and CFP8 form factors. A solution is to stress test transceivers before deploying them in highly demanding environments. It’s also advisable to prioritize transceiver design during the selection process.

Deploying 400G in Your Data Center

Keeping pace with the ever-increasing number of devices, users, and applications in a network calls for a faster, high-capacity, and more scalable data infrastructure. 400G meets these demands and is the optimal solution for data centers and large enterprises facing network capacity and efficiency issues. The successful deployment of 400G technology in your data center or organization depends on how well you have articulated your data and networking needs.

Upgrading your network infrastructure can help relieve bottlenecks from speed and bandwidth challenges to cost constraints. However, making the most of your network upgrades depends on the deployment procedures and processes. This could mean solving the common challenges and seeking help whenever necessary.

A rule of thumb is to enlist the professional help of an IT expert who will guide you through the 400G upgrade process. The IT expert will help you choose the best transceivers, cables, routers, and switches to use and even conduct a thorough risk analysis on your entire network. That way, you’ll upgrade appropriately based on your network needs and client demands.
Article Source: 400G Data Center Deployment Challenges and Solutions
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