Understanding Data Center Interconnect (DCI)

Data Center Interconnect (DCI) is a sophisticated network solution that enables connectivity and communication across data centers.

It boasts features like flexible interconnection, high security, and simplified operation, fulfilling the demand for efficient data exchange and disaster recovery scenarios between data centers.

In the age of cloud-enabled data centers, network resources are virtualized into resource pools allowing business to be decoupled from the physical network.

Through network virtualization, physical network resources can be divided into multiple virtual network resources, thereby boosting the efficiency of network resource utilization.

Virtual network resources are allocated and scheduled according to business needs, thereby optimizing network resource use.

Furthermore, the quick deployment and migration of virtual network resources enhance the flexibility and availability of services.

DCI can be classified according to the data center transmission distance and network connection method:

Classification by Transmission Distance:

  1. Short Distance: Within 5 kilometers, typically using structured cabling to interconnect campus data centers.
  2. Medium Distance: Within 80 kilometers, often used for interconnection in adjacent cities or medium geographical locations using optical modules.
  3. Long Distance: Several thousand kilometers, typically using optical transmission equipment to interconnect long-distance data centers, such as submarine cable networks.

Classification by Connection Method:

  1. Network Layer-3 Interconnect: Different data center front-end networks access each data center via the IP network. If the main data center site encounters a fault, the data that has been replicated to the standby site can be recovered, and applications can be restarted within a brief interruption window. It is essential to protect this traffic from malicious network attacks and ensure it is always available.
  2. Network Layer-2 Interconnect: Building a large Layer-2 network (VLAN) across different data centers primarily meets the demand for server cluster virtual dynamic migration. Factors to consider include low latency, high bandwidth, and high availability.
  3. Storage Network Interconnect: This involves using transmission technology (bare optical fiber, DWDM, SDH, etc.) to replicate disk array data between the main center and disaster recovery center.

The Urgent Need for DCI

With the expansion of user business scale and range, users may need to establish data centers at multiple geographical locations to meet business demands.

These data centers need to be interconnected and share resources. Some applications might require migration, replication, backup and other operations across multiple data centers.

While other applications might need quick load balancing and disaster recovery switching between different data centers.

Specific demands include:

  • Cross-DC Deployment: Some customer businesses might be deployed across DCs. For instance, a customer might delineate a separate VPC for a large website, which might span multiple DCs. Thus, there's a demand for cross-fabric traffic within this VPC, with routing and firewalls needing to be isolated.
  • Intercommunication Between Businesses: Customers may delineate different VPCs for different businesses, which might be deployed in different DCs. If there's a need for intercommunication between businesses, VPCs must support cross-DC L3 intercommunication.
  • Business Disaster Recovery/Active-Active: Business disaster recovery and active-active mainly fall into two categories. For relatively new business systems, customers can use GSLB (Global Server Load Balancing) for disaster recovery and active-active. Specifically, the same business is deployed in two DCs, with the business being the same but the IP addresses being different. This allows for disaster recovery for both systems. This approach doesn't have any specific network demands. However, for some older systems, the requirement is that the IP address cannot change after migration to the disaster recovery center. In this case, support for cross-DC layer-2 intercommunication is needed.

If you need a DCI solution for your data center, feel free to reach out to fibeye.