Understanding AT&T Secure Cloud Interconnect: How It Links Enterprises to Public Clouds

What AT&T Secure Cloud Interconnect Provides

AT&T Secure Cloud Interconnect (SCI) is a dedicated, private network service that links an enterprise's on‑premises data center directly to major public‑cloud platforms such as Amazon Web Services, Microsoft Azure, and Google Cloud. By bypassing the public internet, SCI delivers predictable latency, higher bandwidth, and end‑to‑end encryption, making it suitable for workloads that demand strict security and performance guarantees.

Core Architecture and How It Works

SCI leverages AT&T's MPLS backbone and its extensive fiber footprint. The service establishes a point‑to‑point Ethernet circuit from the customer's edge router to a cloud provider's peering location. At each end, a virtual routing and forwarding (VRF) instance isolates the cloud traffic from other WAN traffic. Data is encrypted using IPsec tunnels or MACsec on the physical link, depending on the customer's security policy.

Key Security Features

Security is built into every layer of SCI:

• Encryption at rest and in transit: IPsec (AES‑256) or MACsec protects data moving across the circuit.
• Segmentation: VRF isolates cloud traffic from corporate WAN traffic.
• Access controls: Integrated with enterprise identity providers for role‑based access to cloud endpoints.
• Monitoring and logging: AT&T's Network Operations Center provides real‑time flow logs and anomaly detection.

Deployment Options and Cloud Provider Coverage

AT&T offers two primary deployment models:

• Direct Connect: A physical fiber circuit from the customer's premises to the cloud provider's data center. Ideal for high‑throughput, latency‑sensitive applications.
• Virtual Connect: A virtual circuit over AT&T's MPLS network, useful when a physical path is impractical or when rapid provisioning is required.

Current cloud partner coverage includes AWS Direct Connect locations, Azure ExpressRoute points of presence, and Google Cloud Interconnect sites across North America, Europe, and APAC.

Performance Benefits Compared to Public Internet

Because SCI does not traverse the public internet, enterprises see measurable gains:

Use Cases Where SCI Adds Value

Enterprises adopt SCI for scenarios that cannot tolerate internet‑level variability:

• Real‑time analytics and streaming data pipelines that require sub‑50 ms latency.
• Regulated industries (finance, healthcare) that must meet data‑in‑transit encryption and segregation mandates.
• Hybrid‑cloud disaster recovery where rapid, reliable replication is critical.
• Large‑scale migration projects that need predictable bandwidth to move terabytes of data.

Pricing and SLA Considerations

Pricing is based on circuit speed (e.g., 1 Gbps, 10 Gbps), distance, and chosen security option. AT&T publishes a Service Level Agreement that guarantees 99.9 % availability and specifies latency caps per region. Customers should evaluate total cost of ownership against alternatives such as VPN over internet or third‑party SD‑WAN solutions.

Getting Started with AT&T SCI

To initiate an SCI deployment, an enterprise typically follows these steps:

Conclusion

AT&T Secure Cloud Interconnect delivers a private, encrypted pathway between on‑premises infrastructure and leading public‑cloud platforms, offering lower latency, higher reliability, and compliance‑ready security. Organizations that rely on mission‑critical cloud workloads or must meet strict regulatory standards find SCI a compelling alternative to standard internet‑based connections.