PulseGuard: Real-time Heart Monitoring with eBPF & Cilium

#ebpf #cilium

**What if we could detect heart attacks early — not just through
medical devices, but through observability in the cloud?

PulseGuard demonstrates how eBPF-based observability can be used for real-time health monitoring, detecting anomalies (like abnormal pulse), and sending alerts.

PulseGuard simulates continuous heart rate monitoring, detects irregular pulse patterns, and integrates with eBPF and Cilium to show how system-level observability tools can detect, trace, and alert health-related anomalies in real-time.

What is eBPF & Cilium?
eBPF (extended Berkeley Packet Filter) is a revolutionary technology within the Linux kernel that allows for the safe and efficient execution of custom programs in the kernel space. Traditionally, kernel modifications required recompiling the kernel or loading kernel modules, which could be complex and risky. eBPF provides a mechanism to run sandboxed programs within the kernel, enabling dynamic programmability and extending its functionality without modifying the kernel source code. This capability is particularly powerful for networking, security, and observability, allowing for high-performance packet processing, custom security policies, and deep insights into system behavior.

Cilium is an open-source, cloud-native networking, security, and observability solution specifically designed for containerized workloads, particularly in Kubernetes environments. It leverages the power of eBPF to provide secure and high-performance communication between microservices. Instead of relying on traditional networking constructs like iptables, Cilium utilizes eBPF programs to enforce network policies, perform load balancing, and gather detailed network telemetry directly within the Linux kernel.

Key aspects of Cilium's use of eBPF:
High-performance Networking: Cilium replaces kube-proxy's iptables rules with eBPF programs for efficient service load balancing, reducing overhead and improving network performance.
Identity-based Security: It enforces network security policies based on workload identities (e.g., Kubernetes labels) rather than IP addresses, providing a more granular and robust security model.
Deep Observability: Through its Hubble component, Cilium provides rich network observability by collecting and visualizing network flow data, dropped packets, and policy enforcement events, all powered by eBPF.
Advanced Features: Cilium also offers features like Layer 7 policy enforcement, transparent encryption, and service mesh capabilities, all built upon its eBPF foundation.
In essence, eBPF is the underlying kernel technology that allows for programmable and extensible kernel functionality, while Cilium is a specific application that harnesses eBPF to deliver advanced networking, security, and observability features for modern cloud-native environments.

The PulseGuard smart band, worn on the wrist, continuously tracks the
user’s heart rate in real time. The collected data is sent to a Flask web
application, which acts as the backend server to receive, process, and
visualize pulse readings.

To ensure efficient performance and deep visibility, eBPF is integrated at the
kernel level to monitor network and system metrics, such as data packet
latency and response time between the device, API, and cloud services.

Using Cilium and Hubble, PulseGuard provides advanced network
observability and security insights. Hubble generates live charts and
dashboards that display heartbeat data, latency trends, and alert frequency
allowing both developers and healthcare providers to monitor system health
in real time.

When an abnormal pulse is detected, AWS Lambda processes the data and triggers AWS SNS to send instant notifications to the loved ones’ phones or emails. Meanwhile, CloudWatch tracks all alerts and ensures the entire pipeline from the wristband to notification runs smoothly and reliably.

Why PulseGuard Matters: Survey Insights &
Statistics

According to the World Health
Organization (WHO), cardiovascular
diseases (CVDs), including heart
attacks, are the leading cause of death
globally, accounting for an estimated
19.8 million deaths in 2022.

In the United States alone,
approximately 805,000 heart attacks
occur each year, of which around
605,000 are first-time events and
200,000 are recurrent attacks.

So what does eBPF do here?

eBPF helps PulseGuard monitor network and system activity at the kernel level,
providing deep observability, performance insights, and enhanced security for the
app’s data flow.

Kernel-Level Monitoring:
eBPF runs inside the Linux kernel and can observe every network packet or system call without changing the app’s code. For PulseGuard, this means it can track how heart-rate data is sent, processed, or transmitted securely.

Real-Time Performance Insights:
eBPF collects metrics like latency, CPU usage, and memory performance for the processes handling PulseGuard data. This helps detect delays or spikes that could affect real-time monitoring.

Security & Data Protection:
eBPF can detect unusual system or network behaviors like unauthorized data access or suspicious traffic ensuring PulseGuard’s sensitive health data remains secure.

Efficient Observability:
Instead of using heavy monitoring agents, eBPF provides lightweight, event-driven insights directly from the kernel so PulseGuard runs faster and more efficiently.