Integrating solutions with existing systems

Identity Federation and Access Management

Identity Federation allows organizations to link their existing identity systems with Google Cloud. By using Cloud Identity, businesses can manage users and groups in one central place while connecting to other providers. This process ensures seamless data flow and consistent security policies across different environments. It is a key part of integrating cloud solutions with existing on-premises systems during a migration.

When designing a unified framework, an External Identity Provider (IdP) like Active Directory or Okta often serves as the Source of Truth. This means all user information is managed in the external system and then synchronized with Google Cloud. Using an external IdP enables Single Sign-On (SSO), which lets employees use one set of credentials to access all services. This reduces administrative work and improves the overall user experience for the workforce.

Creating a Migration Plan requires choosing the right strategy for moving existing user accounts into the cloud. Some organizations use Federation with User Account Consolidation to merge personal consumer accounts into managed corporate accounts. Other plans, like Delayed Federation, involve migrating all users before turning on SSO to avoid locking people out of their accounts. Careful planning prevents conflicting accounts and ensures operational continuity during the transition.

The SAML Assertion is a secure message sent from the IdP to Google to prove a user's identity. It is important to align session lengths between the IdP and Google so that users are prompted to sign in again at the right times. Administrators should also minimize the amount of data sent in these messages to keep the authentication process efficient. Using google.com as the standard issuer helps maintain compatibility across all Google services.

Multi-Factor Authentication (MFA) adds a vital layer of protection by requiring a second form of verification, such as a phone code. For Super-Admin Users, it is a best practice to enforce Google 2-Step Verification because these accounts can sometimes bypass standard SSO settings. Disabling SSO for these high-level accounts can also reduce risk if the external IdP is ever compromised. Consistent security policies must be applied to all users to prevent unauthorized access to sensitive data.

Automated User Provisioning ensures that the lifecycle of a user account in Google Cloud matches the external system. When an employee joins or leaves, a provisioning tool automatically creates or suspends their account to keep the environment secure. This automation reduces manual errors and prevents orphaned accounts from remaining active after an employee departs. Key tools for this include:

• Google Cloud Directory Sync (GCDS) for connecting with Active Directory.
• Built-in connectors for cloud providers like Okta or Microsoft Entra ID.
• HRIS integrations for syncing data directly from Human Resources systems.

Application and Data Interoperability Patterns

When integrating solutions with existing systems, the gated ingress pattern is essential for managing how data enters a cloud environment. Using Apigee as an API platform allows architects to provide security, rate limiting, and analytics for traffic coming from on-premises or other clouds. This setup ensures that legacy applications can communicate with modern cloud services without compromising safety or performance.

To ensure seamless data flow, several networking tools work together to create a secure path between environments. A Private Service Connect endpoint allows for private communication between VPCs, while an Internal Load Balancer exposes application APIs safely. Architects often use specific tools to establish reliable links between different data centers:

• Cloud VPN: Creates secure, encrypted tunnels over the public internet.
• Cloud Interconnect: Provides a direct, high-speed physical connection to Google Cloud.
• Firewall Rules: Control and filter traffic to prevent unauthorized access to backends.

For stricter security needs, a Transit VPC can be used to perform deep packet inspection on all incoming traffic. This layer often includes Next Generation Firewalls and Intrusion Prevention Services to identify and block threats before they reach the application. By separating security tasks into a dedicated network, organizations can maintain high standards during a phased migration from legacy systems to the cloud.

The Apigee Adapter for Envoy is a lightweight API gateway designed to run close to backend applications in on-premises or multi-cloud settings. It handles authentication and authorization locally, which significantly reduces network latency for users by avoiding unnecessary trips to the cloud. This tool allows the data plane to stay within the company's own network boundaries while still using the cloud for high-level management.

Using the Envoy adapter provides several key advantages for interoperability and operational continuity. It uses asynchronous communication to send analytics data to the cloud management plane without slowing down the actual API traffic. Even if the internet connection is temporarily lost, the Envoy proxy can continue to process calls normally using cached security keys and configurations.

Hybrid Connectivity and Network Integration

Cloud Interconnect provides a way to link your on-premises network to Google Cloud through a high-availability, low-latency connection. There are three primary ways to establish this link:

• Dedicated Interconnect: A direct physical connection between your network and a Google facility.
• Partner Interconnect: A connection provided through a third-party service provider for those who cannot connect directly.
• Cross-Cloud Interconnect: A direct link used to connect Google Cloud to another cloud provider like AWS or Azure. Selecting the right connection type depends on your specific bandwidth needs and your physical proximity to Google's data centers.

To ensure your business stays online, you must design your architecture for a high Service Level Agreement (SLA) . Achieving 99.99% availability requires at least four VLAN attachments spread across two different regions and two metropolitan areas. Using multiple Edge Availability Domains ensures that scheduled maintenance work does not disrupt your entire connection at once. This redundant setup is essential for mission-critical applications that cannot tolerate any downtime.

Security is a top priority when integrating cloud solutions with legacy systems that exist outside of Google Cloud. HA VPN over Cloud Interconnect allows you to encrypt traffic using IPsec tunnels while still benefiting from the high capacity of a physical connection. Additionally, Private Service Connect lets you access Google APIs and services privately, ensuring that sensitive data never travels over the public internet. These tools help maintain compliance with industry regulations while keeping your data flow secure.

Efficient data flow relies on the Cloud Router, which uses the Border Gateway Protocol (BGP) to exchange routing information automatically between networks. By enabling Global Dynamic Routing, your cloud network can share routes across all regions, making it easier to manage complex hybrid environments. Properly configured BGP sessions prevent connection issues like flapping and ensure stable communication. This automation reduces the need for manual updates as your network grows or changes.

Organizations often use a Shared VPC to centralize network management and maintain consistent security policies across multiple projects. For modern applications, Cloud Service Mesh uses Hybrid Network Endpoint Groups (NEGs) to route traffic to services running on-premises or in other clouds. These tools help create a seamless experience for users regardless of where the backend data is physically stored. By integrating these systems carefully, you can ensure operational continuity during and after a cloud migration.