Infrastructure · Software component
Layer-4 Load Balancer
Software componentInfrastructureInfrastructurearc:L4LoadBalancer
A transport-layer load balancer that forwards TCP/UDP connections to replicas using only IP/port information, without inspecting application payloads.
Responsibility. Forwards connections to replicas based solely on transport-layer information.
Also known as: Transport-layer load balancer, Cluster service load balancer, Standard cluster service load balancing, Kubernetes ClusterIP Service, kube-proxy (iptables/IPVS), ClusterIP Service
Variant of Load Balancer abstract
When to choose. Choose when all instances are identical and all requests equivalent, so raw throughput and simplicity outweigh request-aware routing.
Relationships
deployed on structural
reads dependency
is routed to by dynamic
receives data from dynamic
routes to dynamic
alternative to variability
Design guidance
- SHOULD be used for internal pod-to-pod traffic, health checks and metrics scraping with stable internal DNS names.
- SHOULD set session affinity to none for stateless agents so any pod can serve any request.
- SHOULD track only ready endpoints so routing follows pod creation, failure and rolling-update termination automatically.
Quantitative guidance
As stated by the sources; verify before use.
- Handles millions of connections per second with sub-millisecond overhead (Ch1.8).
Classification
- Patterns
- Round-robinRandom selectionClient-IP session affinityRandom pod selection (approximate round robin)
- Technologies
- Kubernetes Service (type LoadBalancer / ClusterIP)Kubernetes Service (type LoadBalancer)Kubernetes kube-proxyiptablesIPVS
- Quality attributes
- Performance efficiency (ISO/IEC 25010)Maintainability (ISO/IEC 25010)
Sources
- Ch1.8: T. Nguyen, "Scalability and Production Deployment," in Mastering Agentic AI Systems: Guide for the NVIDIA NCP-AAI Exam, 1st ed. 2026, ch. 1.8. ISBN: 9798244538229.
- Ch4.3: T. Nguyen, "Container Orchestration and Edge Deployment," in Mastering Agentic AI Systems: Guide for the NVIDIA NCP-AAI Exam, 1st ed. 2026, ch. 4.3. ISBN: 9798244538229.
- Ch4.5: T. Nguyen, "NVIDIA NIM and Triton Inference Server," in Mastering Agentic AI Systems: Guide for the NVIDIA NCP-AAI Exam, 1st ed. 2026, ch. 4.5. ISBN: 9798244538229.
- Ch4.7: T. Nguyen, "Scaling Strategies," in Mastering Agentic AI Systems: Guide for the NVIDIA NCP-AAI Exam, 1st ed. 2026, ch. 4.7. ISBN: 9798244538229.