Cloud Networking & Security Made Clear
Beginner-friendly explanations, diagrams, and step-by-step notes on networking, cloud architecture, traffic flow, and security fundamentals — focused on clarity, not vendor marketing.
Our Mission
Free, foundational education in cloud networking and security — for anyone, anywhere. We believe clarity makes learning accessible to everyone.
Explore Topics
Cloud Network
From 0s and 1s to the cloud — follow data across every layer of the network stack.
Cloud Security
Understand attack types and how to defend against security threats.
What You Will Learn
- Networking fundamentals — OSI, TCP/IP, routing
- Traffic flow — DNS, ICMP, TCP handshakes
- Cloud architecture — data centers, virtualization
- Security basics — firewalls, IDS/IPS, TLS
- DDoS — attack types and mitigation
About Me
I bring over two decades of experience in networking and security, and I continue to expand and share my knowledge through research and blogging, with a strong focus on clarity and practical understanding.
- Network Architecture — Private and Public cloud environments for enterprise customers
- Cloud Infrastructure Design — AWS, Azure, and Oracle Cloud Infrastructure (OCI)
- Network Automation & IaC — Terraform Basics, K8 Cilium
I currently lead Cloud Network & Security for a large bank, managing a large-scale multi-cloud environment. Before this, I spent 16 years with GBM, IBM's representative office in the Middle East.
I strongly believe that anyone with curiosity, consistency, and a willingness to learn can reach meaningful levels in their career. The journey matters more than speed, and clarity makes learning accessible to everyone.
Connect
- 🔗 LinkedIn: linkedin.com/in/nithinvenugopal
- 🌐 Blog: cloudnetworking.ai
- 💻 GitHub: github.com/nithinvenugopal2020
Flow, Connection & Session
Three terms you'll encounter constantly in networking and security — each with a distinct meaning that's easy to confuse.
Flow
One direction of traffic. Defined by the 5-tuple. Two flows make up a full conversation.
Connection
Both directions combined. A full conversation between two devices.
Session
The firewall's internal state record tracking a connection in its session table.
Flow
- Unidirectional — one direction only
- Used heavily in monitoring systems — NetFlow, IPFIX, sFlow
- Widely used in cloud flow logs — AWS VPC Flow Logs, Azure NSG Flow Logs
Think of a flow as one direction of traffic.
Connection
- Bidirectional — both directions combined
- Represents a full conversation between two devices
- TCP connections begin with the SYN handshake
- Often used in traditional firewall terminology
- UDP is connectionless but firewalls still track it as a connection
Think of a connection as a full conversation.
Session
- Original and translated IPs/ports — pre and post NAT
- Policy ID — which rule matched
- Timeout values — when to expire the entry
- Security profile information — AV, IPS, URL filtering
- Byte and packet counters — traffic statistics
Think of a session as the firewall's memory of a conversation.
How They Relate
2 flows, 1 connection, and 1 session entry in the firewall's state table.
Defending Against DDoS Attacks
How modern networks protect applications from volumetric, protocol, and application-layer attacks.
What is a DDoS Attack?
A Distributed Denial of Service (DDoS) attack is an attempt to make an online service unavailable by overwhelming it with traffic from multiple sources.
Testing & Resilience Validation
L3 / L4 Lab Tools
Use only in environments you own or are authorised to test. Focus on behaviour validation and capacity planning.
- hping3 Protocol behaviour testing
- iperf3 Throughput baseline
- tcpdump Packet inspection
Layer 7 Load Testing
Simulate real users and APIs to validate WAF, caching, rate-limiting, and autoscaling.
- ab Apache BenchMark ab -n 5000 -c 200 -v 2 https:
- k6 Scripted HTTP tests
- JMeter API workflows
- Locust User behaviour
- Gatling High-performance load
The Goal of DDoS Protection
The objective is not just to block traffic, but to ensure legitimate users always get through while attacks are absorbed at the network edge.
A Packet Journey
From Your Computer to the Cloud
The Binary World: 0s and 1s
Have you ever wondered how data from your computer actually moves across the internet and ends up in the cloud? Let's start from the very basics.
Computers operate using the binary number system, which has only two digits: 0 and 1. This is different from the decimal system, which has ten digits (0–9).
Example: To convert 13 into binary:
13 = 8 + 4 + 1 = 2³ + 2² + 2⁰
Binary representation: 1101
How Are 0s and 1s Created?
At the lowest level, computers use transistors. A transistor can either be On (1) or Off (0).
Imagine memory as billions of tiny switches. Each switch is called a bit, and eight bits together form a byte.
How Does the Computer Understand Them?
- Hardware layer
- Kernel and device driver layer
- Operating system layer
- Application layer
When you save a file, the application informs the OS, which uses drivers to write data to the hard drive.
Encoding of Data
Every character is encoded for efficient storage and transmission using formats like ASCII or UTF (Unicode).
Example: The word network uses 7 characters → file size is 7 bytes.
MAC vs IP Address
At the software level, systems care about IP addresses. At the local network level, devices use MAC addresses.
MAC addresses are 48-bit (6 octets) identifiers defined by IEEE 802.3 and never leave the local network.
OSI Layers and Packet Formation
- Transport → Segment
- Network → Packet
- Data Link → Frame
- Physical → Bits
Each layer adds its own header. At the destination, headers are removed in reverse order.
Network Media
- Ethernet: electrical pulses over copper or fiber
- Fiber: light pulses over glass
- Wireless: radio waves (WiFi)
- PAN: Bluetooth
Network Topologies
- Bus
- Ring
- Star (most common)
- Mesh
Speed, Bandwidth, Latency & Throughput
Bandwidth: Maximum data capacity (bps).
Latency: Time taken for a packet to travel (ms).
Throughput: Actual successful data rate.
Speed: Physical signal rate of the medium.
Real-Life Example
A 1 Gbps connection = 1024 Mbps = 128 MB/s.
A 1 GB file can be downloaded in about 8 seconds.
The Journey Ends in the Cloud ☁️
The data you're reading travelled from a VS Code , across multiple networks, and reached you via the page hosted in cloud.