In today’s digital era, businesses rely on Data Centers to host and deliver their computing resources and information across the multitude of IT environments found within many organizations. The modern cloud computing model, combined with the pervasiveness of Virtualization, has led businesses from using a single Centralized Data Center to a model in which multiple Data Centers are geographically dispersed and, in some cases, connected to the Cloud and/or are part of a Hybrid Environment.
The challenge in this Connectivity is ensuring that an organization has an infrastructure that connects its data centers efficiently, allowing users, workloads, and applications to work together seamlessly.
Data Centre Interconnect (DCI) addresses this connectivity challenge by providing a layer of connectivity between Data Center Facilities. With DCI, multiple data centers can operate and communicate as if they were part of a single virtual resource pool.
Furthermore, DCI enables an organization with the ability to build an Active/Active architecture for critical IT workloads or to establish a Disaster Recovery site for Redundancy.
DCI also uses New technological advancements, including Ethernet VPN-VXLAN, MPLS, and Transport Protocols (Secure MAC and Secure IP), and today’s DCI Solutions provide much more than just simply connecting Data Center Locations. Today’s DCI solutions focus on connecting intelligence and security across all organizational assets.
What Is Data Centre Interconnect (DCI)?
DCI stands for Data Center Interconnect and refers to the technologies/architecture used to connect two or more geographically dispersed Data Centers, allowing them to operate together as a single unit.
The primary objectives of a DCI solution are:
- High Availability: Seamless failover between sites.
- Workload Mobility: Ability to move VMs, containers, or applications across data centers.
- Data Consistency: Fast and reliable data synchronization and replication.
- Security & Segmentation: Extending network and security policies across sites.
Why DCI Matters
With increasing adoption of hybrid and multi-cloud strategies, organizations need:
- Disaster Recovery between primary and backup data centers.
- Active-Active architectures for real-time application failover.
- Cloud Extension to connect private and public clouds seamlessly.
Common DCI Technologies
| Type | Description | Typical Use Case |
| Layer 2 DCI (VLAN Extension) | Extends VLANs between data centers. Uses VXLAN, OTV, or VPLS. | VM mobility, same subnet extension |
| Layer 3 DCI (IP-based) | Uses BGP, EVPN, or MPLS L3VPN for routing between data centers. | Scalable interconnects, cloud routing |
| Encrypted DCI | Secured using IPSec, MACsec, or TLS tunnels. | Compliance-driven environments |
| Optical DCI | High-speed, low-latency transport using DWDM or dark fiber. | Metro or backbone data center connections |
Modern DCI Architecture: EVPN-VXLAN
Modern data centers increasingly adopt EVPN-VXLAN for DCI because it brings the scalability of IP routing to traditional L2 overlays.
Benefits include:
- Efficient MAC and IP learning using BGP EVPN control plane.
- Multi-tenancy with tenant VRFs and segmentation.
- Seamless integration with cloud and containerized workloads.
- Interoperability with traditional L2/L3 networks.
DCI Architecture Representation
Below is a simplified conceptual diagram representing multi-site DCI connectivity using EVPN-VXLAN overlay:
Design Considerations
When building a DCI, engineers should evaluate:
- Latency & Bandwidth: Critical for storage replication and workload migration.
- Security: Encrypt traffic and protect control-plane sessions.
- Routing Policy: Determine route advertisement and loop prevention.
- Failover Strategy: Decide between Active-Active vs Active-Standby.
- Automation: Use Ansible, Terraform, or vendor APIs for consistency.
Real-World Use Case
A financial organization with two active data centers in different regions used EVPN-VXLAN over MPLS to achieve:
- Active-active services across both sites.
- Policy-based segmentation for regulatory compliance.
- Automatic failover with minimal packet loss.
The outcome: 99.99% uptime and seamless user experience during failovers.
Happiest Mind’s DCI Capabilities
Happiest Minds end-to-end Development and Quality Assurance (QA) Services for Data Center Interconnect (DCI) Solutions covering the complete DCI Development Lifecycle from Feature Development to DCI Validation.
We provide complete DCI solutions through our team of experienced developers, certified testers, and project managers. Happiest Minds Development Services covers the entire DCI Development Lifecycle from Feature Development, DCI Platform Integration and Validation through DCI Scale Testing.
Our development team has extensive experience with both existing and new DCI technologies, including EVPN-VXLAN, BGP, MPLS, and Segment Routing. DCI Data Plane, and DCI Class Devices. Our QA services are focused on all aspects of functional validation, including scale testing, performance benchmarking, resiliency testing, high availability, fast convergence times, and DCI Interoperability across multiple vendor environments.
By employing an Automation First Strategy enabled by Python and APIs, Happiest Minds facilitates the rapid evolution of DCI Networks through Continuous Testing and Fast Feedback Cycles for Customer DCI Networks’ Production Readiness.
DCI Validation Scope and Approach
DCI Validation relates to validating the VXLAN EVPN Multisite and MPLS-based DCI (Data Centre Interconnection) Architectures. Validation occurs on both the Control Plane and Data Plane, confirming the trustworthiness of the inter-data-center connection.
As for Control Plane Validation, we check the accuracy of EVPN routes (MAC/IP, IP Prefixes), DCI Gateway Roles, Site Consistency, Routing Policy Accuracy, and BGP Stability when failures occur and during recovery.
For Data Plane Validation, we ensure traffic is forwarded without interruption over to Multiple Data Centers, providing connectivity at Layer 2 and Layer 3, Inter-VRF communication, Anycast Gateway Operation, Address Synchronization, and VXLAN Encapsulation Accuracy.
Use of AI in DCI Validation
Happiest Minds aims to leverage AI capabilities within DCI validation to improve both Test Efficiency and Test Accuracy. AI-driven methodologies enable the analysis of large amounts of data from test results, identify anomalies, and predict Control Plane and Data Plane behavior during failures. By combining both AI and Automation, Happiest Minds can accelerate root cause analysis, enhance intelligent test coverage, and deliver improved quality assurance, reliability, and resilience for DCI implementations.
is a Test Architect at Happiest Minds. He has over 13 years of experience in networking, bringing extensive hands-on experience in both manual and automation testing. His expertise lies in networking, ethernet, wireless, and satellite communications.
In his role, Viswesh has taken the lead on various feature releases for an existing customer, focused on the DPI space. He has actively contributed to developing test automation frameworks and has been instrumental in creating, enhancing, and troubleshooting test scripts. Over the course of his 13-year career, Viswesh has collaborated with many global networking companies and successfully delivered network test solutions.
