Architect Secure Application Delivery and Traffic Management with Load Balancers

Load balancers in Google Cloud sit at the network edge and handle incoming traffic before it reaches your applications. Google Cloud provides different load balancer types depending on your needs: global external Application Load Balancers work across multiple regions, regional external Application Load Balancers serve a specific area, and Network Load Balancers handle TCP/UDP traffic. Each type supports different protocols including HTTP, HTTPS, HTTP/2, TCP, UDP, and SSL, so you can match the load balancer to your application's requirements.

Cloud Armor attaches to load balancers and provides security policies that filter malicious traffic before it enters your network. You can create rules that allow, deny, or slow down traffic based on factors like where the request came from, what IP address it uses, and what the request contains. Cloud Armor includes pre-built Web Application Firewall rules that protect against common attacks like cross-site scripting and SQL injection, which are part of the OWASP Top 10 list of web security threats. These rules run at Google's network edge, closest to where traffic originates, so attackers waste their resources before reaching your backend systems.

SSL/TLS termination lets the load balancer handle encryption so your backend servers don't have to process that overhead. External proxy Network Load Balancers and Application Load Balancers let you control which TLS versions and cipher suites are accepted, keeping weak encryption out of your system. Backend servers can still communicate using HTTPS or SSL to keep data encrypted throughout its journey. This two-layer approach protects data in transit while reducing the processing load on your application servers.

DDoS protection comes automatically with external load balancers through Cloud Armor's always-on defenses, with additional advanced protection available for paid subscribers. Adaptive Protection watches traffic patterns to spot Layer 7 DDoS attacks and can automatically create WAF rules to counter them. This smart detection helps block new attack types without requiring you to manually configure rules for every threat.

Establish Trust and Secure Communications with Certificate Authority Service

Certificate Authority Service (CA Service) manages private certificates for your organization without requiring you to run your own certificate infrastructure. You can create a custom Public Key Infrastructure hierarchy by setting up private root certificate authorities, subordinate CAs, or connecting to existing on-premises roots. Administrators group CAs into pools to distribute the workload of issuing certificates and handle high volume across multiple projects. This private trust system ensures that only cryptographically validated entities can access your internal services.

Private keys are protected using Cloud HSM, which meets strict federal security standards (FIPS 140-2 Level 3) for hardware security. You control who can issue certificates by combining Identity and Access Management permissions with VPC Service Controls, which prevents unauthorized certificate creation and stops data from leaving your network. Administrators set up issuance policies and certificate templates to standardize how certificates are created, including which encryption algorithms to use, what names to include, and how long certificates remain valid. All certificate activities are logged through Cloud Audit Logs so you can prove compliance during security reviews.

Certificate Manager works with CA Service to automatically provision TLS certificates for load balancers and internal services. Certificates issued by your private CAs can be deployed directly to both global external and regional internal Application Load Balancers. You configure certificate maps to bind issued certificates to HTTPS proxies, which automates TLS termination at scale. This automation prevents security gaps that occur when certificates expire and nobody renews them.

Private certificates from CA Service support several critical security functions across your environment. They enable mutual TLS authentication between microservices, where both sides verify each other's identity before exchanging data. They authenticate devices, IoT equipment, and automated pipelines without relying on public certificate authorities. They also ensure strong encryption for traffic crossing network boundaries and hybrid connections. This centralized certificate management keeps all your communications secure and compliant with organizational policies.

Design and Implement Granular Access Policies with Cloud NGFW and Identity-Aware Proxy

Cloud Next Generation Firewall (Cloud NGFW) and Identity-Aware Proxy (IAP) work together to enforce zero-trust security, where no user or device gets automatic trust simply by being on your network. Cloud NGFW operates at the network layer to control traffic between workloads, while IAP operates at the application layer to verify who is accessing what. This combination moves security from the network edge to individual users and workloads, ensuring every access attempt gets verified.

Cloud NGFW provides a distributed, stateful firewall that enforces security policies at the organization, folder, and VPC network levels. You can create micro-segmentation rules that control traffic between specific workloads, even between machines in the same VPC network. Firewall rules can use IAM-governed tags to dynamically apply policies to groups of virtual machines or GKE clusters, threat intelligence feeds to automatically block known malicious IP addresses, and Intrusion Prevention System capabilities to detect malware, spyware, and command-and-control attacks. This layered approach stops both broad-based threats and targeted attacks.

Identity-Aware Proxy (IAP) acts as a gatekeeper for applications and administrative access ports like SSH and RDP. It verifies user identity before allowing any connection, regardless of where the user is located on the network. IAP evaluates multiple factors before granting access: the user's identity and group membership from Cloud Identity or a federated identity provider, the device's security posture, and the user's location or IP address. This context-aware approach means access decisions consider not just who you are, but also what device you're using and where you're connecting from.

Using Cloud NGFW with IAP creates a layered defense where network-level rules block unwanted traffic while application-level checks verify individual users. For example, Cloud NGFW can restrict backend services to accept traffic only from frontend tiers, while IAP ensures only authenticated developers from trusted networks can access SSH on those backend VMs. Both services support automation through Infrastructure as Code tools like Terraform, allowing consistent security deployments that scale as your cloud environment grows.