Cloud Interconnect

AWS Direct Connect provides dedicated network connections between your on-premises infrastructure and AWS. Unlike internet-based connections, Direct Connect offers consistent bandwidth, lower latency, and a private connection that does not traverse the public internet.

Dedicated vs Hosted Connections offer different deployment models. Dedicated connections provide a physical 1Gbps, 10Gbps, or 100Gbps port at a Direct Connect location. You manage the networking equipment and establish BGP sessions. Hosted connections are provided through AWS Direct Connect Partners who manage the physical infrastructure, offering speeds from 50Mbps to 10Gbps. Hosted connections are faster to provision and require less networking expertise.

Link Aggregation Groups (LAGs) bundle multiple physical connections for increased bandwidth and redundancy. Combine multiple 1Gbps connections into a LAG providing 2Gbps, 4Gbps, or higher aggregate bandwidth. LAGs use LACP (Link Aggregation Control Protocol) for automatic failover between member connections. If one connection fails, traffic automatically shifts to remaining connections without disrupting active sessions.

VLAN Configuration isolates traffic over shared Direct Connect connections. Each VLAN corresponds to a private VIF (Virtual Interface) connecting to a single VPC. Create multiple VLANs on a single connection to reach multiple VPCs. Public VIFs provide access to AWS public services like S3 and DynamoDB endpoints without internet gateway routing. Transit VIFs connect to Transit Gateway for hub-and-spoke architectures.

Resilience Design requires careful planning. AWS recommends at least two connections in different physical locations for production workloads. Deploy connections to different Direct Connect locations with diverse fiber paths. Configure BGP with appropriate AS-path prepending for traffic engineering. Use Transit Gateway with multiple Direct Connect gateways for automatic failover.

Bandwidth and Latency characteristics differ from internet connections. Direct Connect provides dedicated bandwidth not shared with other customers. Latency is deterministic and lower than internet paths since the connection follows optimized physical routes. For example, a Direct Connect between New York and US-East-1 typically provides 2-4ms latency versus 10-20ms over the internet. This consistency is critical for applications like real-time analytics and database replication.

SD-WAN and Transit Gateway provide flexible, scalable connectivity architectures for multi-site and hybrid cloud environments.

SD-WAN Integration with cloud connectivity creates intelligent, automated networking. SD-WAN appliances aggregate multiple transport types (MPLS, broadband, LTE) and dynamically route traffic based on application requirements. Integrate SD-WAN with Direct Connect by advertising SD-WAN routes through BGP over Direct Connect. This provides application-aware routing: critical traffic uses Direct Connect for performance, while less sensitive traffic uses broadband for cost savings.

AWS Transit Gateway acts as a central hub connecting VPCs, on-premises networks, and other cloud providers. A single Transit Gateway can connect up to 5000 VPCs and 1000 on-premises networks through VPN. Transit Gateway routes traffic between attachments using route tables, enabling hub-and-spoke, full-mesh, or shared-services architectures.

Transit Gateway Architectures solve common multi-VPC connectivity challenges. The hub-and-spoke model centralizes shared services (security, logging, DNS) in a shared VPC, with spoke VPCs connecting through the hub. The full-mesh model provides direct connectivity between all VPCs. The mixed model combines hub-and-spoke for shared services with direct peering for high-traffic pairs.

Global Backbone using AWS Global Accelerator or Direct Connect Gateway provides low-latency connectivity across regions. Direct Connect Gateway extends a single Direct Connect connection to VPCs in any AWS Region. This eliminates the need for separate connections to each region. For global architectures, combine Direct Connect in each region with Transit Gateway peering for seamless cross-region connectivity.

Multi-Cloud Connectivity extends Transit Gateway to other cloud providers. Use Site-to-Site VPN from Transit Gateway to Azure Virtual Network or GCP VPC. For dedicated connectivity, use third-party network providers that offer multi-cloud interconnect services. These providers establish connections to multiple cloud providers from their network, reducing the need for separate interconnects to each provider.