What is Data Center Interconnect (DCI)? A Complete Guide
Data centers have become the beating heart of digital business. Everything from financial transactions to cloud-based collaboration tools depends on the seamless movement of information between these high-powered facilities. As demand for bandwidth grows and companies stretch their networks across cities, states, and continents, the ability to connect data centers securely and efficiently has taken on new urgency. But linking data centers isn’t as simple as laying fiber between buildings. You’re dealing with huge volumes of traffic, low-latency expectations, and the need for airtight security.
Enter Data Center Interconnect — the infrastructure that links your critical assets and keeps operations moving. In the sections that follow, you’ll learn what Data Center Interconnect is and its objectives, along with the technologies and architectures that enable it.
What is data center interconnect?
Data center interconnect (DCI) is the networking infrastructure that links two or more data centers together. Many businesses maintain multiple data centers, and DCI allows for the fast, secure, and reliable exchange of data across these geographically separate facilities. It relies on many technologies, including high-capacity fiber links, software-defined networking (SDN), and Dense Wavelength Division Multiplexing (DWDM).
DCI is used by organizations in finance, healthcare, and many other industries, but the fastest growing driver behind DCI is artificial intelligence (AI). AI workloads demand immense compute power and generate massive amounts of data. These requirements also place extraordinary pressure on physical resources like energy and cooling, which limits how much AI infrastructure you can build into any single data center. As an example: “When they try to do a cluster of 200,000 GPUs or even 100,000 GPUs, you soon hit 300 megawatts, and 300 megawatts is not available inside one physical building today,” according to Ram Velaga, senior vice president and general manager of the company’s core switching group To meet demand, businesses are distributing AI infrastructure across multiple sites. That distribution only works if those sites stay tightly connected, and DCI is what makes that possible.
As organizations scale up operations, they’re turning to larger and more powerful facilities to house their infrastructure. These are known as hyperscale data centers, and their rise has reshaped how DCI is designed and deployed.
DCI and hyperscale
Hyperscale data centers are massive facilities designed to support thousands of servers and petabytes of storage. You’ll find them powering the biggest names in cloud computing, social media, and AI. These centers are optimized for efficiency, allowing organizations to run high-demand workloads while keeping energy and operational costs down.
But the real power of hyperscale isn’t the result of a single facility. It comes from the ability to connect multiple hyperscale locations into a cohesive, intelligent network. That’s where DCI comes in. Through low-latency, high-bandwidth interconnects, you can build a global network of hyperscale assets. Without DCI, scaling operations to this level would be impossible.
The objectives of DCI
By linking data centers effectively, you unlock a range of benefits that prepare your organization for the future. Here are several key objectives that DCI can help your company achieve.
Reducing operational costs
When your data centers work together, efficiency goes up and costs go down. Multiple data centers can share processing power, storage capacity, and more. This leads to less duplicate infrastructure and lower capital expenses. DCI also enables companies to reduce their reliance on the public cloud, keeping bandwidth charges down. In addition, as data centers are built in rural areas that offer less expensive real estate and lower energy costs, DCI facilitates links back to centers in more populated areas. And if there’s a disaster that takes one data center out of commission, DCI makes the process of switching to another center more efficient, mitigating operational impact and associated expenses.
Strengthening disaster recovery
With DCI, your organization can create backups across geographically distributed sites. That means if one facility goes offline due to a power outage, natural disaster, or security breach, your data and applications remain safe and accessible elsewhere. This redundancy is essential for business continuity, allowing critical operations to continue without downtime.
Improving access and connectivity
DCI improves the availability of data and applications for users across regions. Employees, customers, or partners can access information from the nearest data center and reduce lag time. If you’re supporting a hybrid workforce or a global customer base, DCI ensures your infrastructure keeps up with demand and maintains a seamless experience no matter where users are located.
Enhancing data security
Security is a core component of any interconnect solution. Modern DCI implementations support robust encryption protocols that protect data while it’s in motion, ensuring sensitive information stays secure between sites. Along with other key security features, this empowers DCI to help organizations meet strict compliance standards without compromising performance.
Supporting dynamic load balancing
One of the more technical but powerful uses of DCI is in dynamic load balancing. With multiple data centers connected through high-speed links, your organization can distribute traffic based on current demand and available resources. This prevents bottlenecks at busy locations and makes the most out of your infrastructure. Whether it’s shifting compute-intensive AI models to a less active site or rebalancing storage access during peak hours, DCI gives you the agility to optimize performance across the board.
Constraints and challenges of DCI
Data center interconnect is powerful, but implementing it comes with its share of challenges. The more your organization depends on multiple data centers for performance, availability, and regulatory compliance, the more pressure you’ll face to get your DCI design right. Below are several key obstacles — and how the right networking solutions partner can help you navigate them effectively.
Ensuring redundancy and availability
High availability DCI systems require proper redundancy. If a single interconnect fails and no alternate path exists, your data and applications could be cut off. Your DCI architecture can address this concern by using secondary DCI links across diverse fiber paths along with multiple vendors. This approach avoids single points of failure and keeps mission-critical services running. A trusted network service provider can help protect your DCI from unexpected disruptions by ensuring these and other best practices are woven into the fabric of your network from the start.
Managing a complex setup process
Building out DCI infrastructure involves everything from coordinating routing protocols to network traffic engineering. Especially for enterprises without deep internal networking expertise, all this leads to a steep learning curve. Partnering with a provider that specializes in DCI streamlines setup significantly. They can quickly identify the right technologies for your needs and ensure that everything is aligned for performance, security, and compliance from day one.
The best partners offer managed optical fiber networks (MOFN). An MOFN offers the high level of control and performance of a private network along with the ease-of-use that comes with managed networking services. This is because an MOFN offers dedicated service to the customer while being fully owned and operated by the network service provider.
Handling multiple carrier relationships
Many DCI strategies rely on more than one carrier for redundancy and geographic reach. But juggling those relationships — and all the minutiae that comes with them — takes valuable time and energy from your IT team. Miscommunication between providers can also lead to performance issues and unnecessary downtime.
When you work with a provider that has strong relationships with a broad range of vendors, they can take over the task of coordinating these carriers for you. That means fewer headaches and a single point of contact for troubleshooting, planning, and upgrades.
Maintaining robust security
As soon as your data travels between sites, it becomes vulnerable to interception or misuse, especially if it crosses public or third-party infrastructure. Encryption is a must, but it’s not the only consideration. An experienced networking partner can help you integrate multi-layered security into your DCI strategy.
Planning for future scalability
Your data needs of tomorrow will likely look substantially different than those of today, and your DCI strategy must scale and evolve to meet them. Planning for growth without overbuilding is one of the most difficult balancing acts in network design. A solutions partner with deep DCI experience can help future-proof your network. They’ll ensure your network can grow with demand instead of holding you back.
Types of DCI architecture
There’s no one-size-fits-all model for DCI. Below are several widely adopted DCI architectures, each suited to different organizational needs.
Point-to-point interconnects
Point-to-point interconnects are the simplest form of DCI. This setup involves a direct connection between two data centers. It’s ideal for datacenter operators and enterprises that only need to link sites, across short distances. While point-to-point interconnects are relatively easy to manage and secure, they lack flexibility and scalability. If you later expand to additional sites, you may need to shift to a more scalable architecture.
Multipoint interconnects
Multipoint DCI expands on point-to-point by connecting more than two data centers in a network. While this architecture introduces more complexity, it also improves resource utilization and redundancy.
Meshed interconnects
A meshed interconnect is a resilient DCI structure. In this model, data centers are connected in a web or grid-like architecture. Meshed DCI is more expensive and complex to manage, but it offers high availability and redundancy. It’s a strong choice for companies with critical workloads that require continuous uptime across global or regional data centers.
Hub-and-spoke interconnects
The hub-and-spoke model uses one central data center (the hub) that connects to multiple satellite sites (the spokes). Each spoke links only to the hub, not to each other. This architecture enables centralized management of the centers and can reduce costs by concentrating networking equipment at the core. However, performance depends heavily on the availability and capacity of the hub.
Software-defined interconnects
Software-defined interconnects (SDI) uses SDN to manage the network through software instead of provisioning and configuring physical links one at a time. SDI boosts flexibility and simplifies policy enforcement. With SDI, organizations can adapt their interconnect strategies in real time, reacting quickly to changes in demand or infrastructure.
Cloud interconnects
Cloud interconnects refer to DCI solutions that link data center infrastructure with cloud service providers. These enable resource sharing between on-premises centers and either public or private cloud platforms. Cloud interconnects combine the power of linked data centers with the scalability of cloud services.
Enterprise interconnects
Enterprise interconnects involve connecting a company’s own private data centers — whether for redundancy, compliance, or performance. These networks tend to prioritize security, availability, and tight integration with internal systems. Enterprise DCI solutions allow for more granular control over all aspects of your deployment.
High-density cloud interconnects
High-density cloud interconnects link multiple cloud data centers across vast geographic regions. These environments support high volumes of dynamic traffic, enabling providers to better meet the demands of AI and always-on services.
DCI technology components
Effective data center interconnect relies on a suite of underlying technologies that work together to move data securely and efficiently between facilities. Below are some of the most essential technologies for modern DCI.
Fiber optic cables
Fiber optic cabling is the foundation of any DCI deployment. These cables transmit data as pulses of light, allowing for extremely high transmission speeds and long-distance communication with minimal signal degradation. Because they use light rather than electrical signals, fiber optics are immune to electromagnetic interference and support higher bandwidth compared to copper cabling.
For DCI, single-mode fiber cables are generally preferred for long distances due to its ability to carry data over distances of up to 100 kilometers or more without amplification, while multi-mode cables may be used for connecting centers over shorter distances. The quality and layout of your fiber optic network has a direct impact on the speed, reliability, and flexibility of your interconnect strategy.
Networking equipment
Core networking equipment powers the transmission and management of data across your DCI infrastructure. This gear includes routers, switches, transponders, and muxponders. Routers and switches direct traffic along optimal paths, while transponders convert electrical signals into optical ones (and vice versa). Muxponders, on the other hand, combine multiple lower-speed data streams into a single higher-speed stream, maximizing the use of available bandwidth. Selecting high-performance equipment is especially important in DCI settings, where massive data volumes and demanding latency requirements leave little room for bottlenecks.
Wavelength-division multiplexing
Wavelength-division multiplexing (WDM) dramatically increases the capacity of fiber optic connections by enabling multiple data signals to be transmitted simultaneously on different wavelengths of light. This allows a single fiber pair to carry many individual data streams without interference. There are two main forms of WDM used in DCI: coarse WDM (CWDM) and dense WDM (DWDM). DWDM is preferred for high-capacity interconnects because it supports tighter wavelength spacing and greater total bandwidth, albeit at a higher cost.
Software-defined networking (SDN)
SDN brings programmability and automation to DCI. It separates network control and forwarding, so administrators can manage all aspects of the network through centralized software. This makes it easier to deploy, scale, and modify DCI environments in real time.
Optical transport network (OTN)
An optical transport network (OTN) is a standardized digital wrapper used to organize, monitor, and transmit optical signals across fiber infrastructure. It functions like a shipping container for data, packaging payloads into units that can be managed more easily across long distances through various types of network hardware. OTN delivers the reliability, visibility, and operational efficiency required to run mission-critical applications across a distributed infrastructure like DCI.
Connect your data centers with confidence
When implemented correctly, data center interconnect opens the door to improved redundancy, real-time data availability, stronger disaster recovery, and better access to both private infrastructure and public cloud platforms. At the same time, DCI presents challenges, from maintaining security and managing multiple vendors to ensuring your network can scale as demands evolve.
That’s why you need a partner who can deliver performance without compromise. Ribbon Communications provides a complete solution set for DCI, with do-it-yourself automation, ecosystem integration, and unmatched performance, offering 25.6T density in a 2RU platform with wavelengths up to 1.2T. This high density comes at an incredibly low power consumption of 0.07W/G. Together with an external management portal, built-in drag and drop workflow capabilities, and a fully modular optical architecture, all this means one thing: Ribbon is the right way to take your data center to the next level with DCI.
If you’re ready to leverage the benefits of data center interconnect, explore Ribbon’s DCI solutions today.
