By Arpacore Team22-APR-2025

What is a DDoS attack and how to defend against it

What Is a DDoS Attack?

As a software development agency, we are often asked about digital threats that could compromise the reliability of a platform. One of the most critical — and often misunderstood — threats is the DDoS attack. Understanding what it is, how it works, and how to defend against it is essential for any business that relies on its online services. In this article, we will explain DDoS attacks in plain language, outline real-world implications, and provide strategies that we implement to protect our clients’ infrastructure.

Defining the Threat: DDoS in Simple Terms

DDoS stands for Distributed Denial of Service. It’s an attack in which multiple systems — often thousands of hijacked devices across the globe — flood a server, website, or network with so much traffic that it can no longer operate normally. Imagine trying to walk into a store but finding the entrance blocked by a crowd of fake customers. That’s what happens during a DDoS attack: legitimate users are prevented from accessing your service because malicious traffic has overwhelmed it.

Unlike a typical hacking attempt, a DDoS attack doesn’t try to steal data or break into the system. Its goal is to disrupt. And disruption can be expensive: lost sales, frustrated users, reputational damage, and even penalties if critical services go down for extended periods.

How a DDoS Attack Works

The key to a DDoS attack is scale. An attacker first compromises a large number of internet-connected devices — computers, servers, even smart TVs or IoT devices. These are collectively known as a “botnet.” Each infected device can send traffic to the target server on command.

When activated, the botnet sends a flood of requests to the target — often millions per second. This can overwhelm even well-architected systems if they’re not designed to handle unexpected surges in traffic. Because the requests are coming from seemingly normal devices scattered around the world, filtering out malicious traffic without blocking real users becomes a complex challenge.

Why You Should Care — Even as a Small Business

You might assume DDoS attacks only target large corporations, governments, or tech giants. But that’s no longer true. Smaller businesses are often targeted precisely because they lack sophisticated defenses. A 15-minute outage can be devastating for an online store during a sales campaign, or for a SaaS app that clients rely on for their daily work. DDoS protection is not just a big-business concern — it's part of modern digital hygiene.

Types of DDoS Attacks

Understanding the different forms DDoS attacks can take is key to building the right defenses. Here are the main categories:

  • Volume-Based Attacks: These aim to consume all available bandwidth. They include UDP floods, ICMP floods, and other packet-based floods that saturate the network.
  • Protocol Attacks: These exploit weaknesses in Layer 3 and 4 of the OSI model (network and transport layers). A common example is the SYN flood, which exploits the TCP handshake to consume server resources.
  • Application Layer Attacks: These are more sophisticated. They mimic legitimate user behavior — such as sending HTTP GET requests — but do so at scale, targeting the application itself rather than the network.

Some attackers even combine multiple attack types simultaneously, in what’s known as a “multi-vector” attack. This makes them harder to detect and neutralize.

Real-World Scenarios: What Happens During a DDoS

Here’s how a DDoS attack can impact your service:

  • Your website becomes slow, then completely unreachable.
  • Your backend API starts timing out, causing mobile apps and frontend interfaces to fail.
  • Your customer support team is overwhelmed with calls or chats from frustrated users.
  • Your payment gateway cannot process transactions, causing sales to drop to zero.
  • Your cloud provider sends you unexpected bills due to the volume of traffic.

And the worst part? The attack can last for hours, days, or even repeat in waves — unless you have the proper infrastructure in place.

How We Design Defenses at Arpacore

At Arpacore, we believe in proactive defense — not just reactive firefighting. When we design software solutions for our clients, we include multiple layers of DDoS mitigation. Here's what that involves:

1. Content Delivery Networks (CDNs)

Services like Cloudflare, AWS CloudFront, and Akamai act as a protective layer. They cache content globally and absorb large volumes of traffic at the edge, preventing your origin server from being overwhelmed.

2. Rate Limiting

We implement logic that limits how many requests can be made per IP address or session in a given time. This helps filter out automated attack traffic without affecting real users.

3. Web Application Firewalls (WAFs)

WAFs examine incoming requests and filter out malicious patterns. They can block SQL injection attempts, fake form submissions, and known bot signatures — all before the request reaches your application code.

4. Scalable Infrastructure

We use cloud environments with autoscaling capabilities so that resources can be temporarily expanded to absorb unexpected traffic surges. Combined with horizontal scaling, this allows your service to remain available under stress.

5. Traffic Monitoring and Alerting

Using tools like Datadog, AWS CloudWatch, and custom logs, we detect anomalies in traffic patterns and set up automated alerts for suspicious behavior — allowing us to respond in real time.

6. Emergency Response Playbooks

We prepare predefined response strategies so that if an attack occurs, our team and yours know exactly what to do — from switching DNS routing to activating WAF rules or contacting cloud security support.

Should You Invest in Paid Protection Services?

There are specialized DDoS mitigation providers like AWS Shield Advanced, Cloudflare Enterprise, and Radware. These services offer SLA-backed protection, real-time threat intelligence, and rapid response teams. For businesses handling sensitive operations — like finance, healthcare, or high-traffic SaaS — investing in these services may be not just smart, but essential.

The Cost of Doing Nothing

Here are some numbers to consider:

  • Average DDoS downtime: 6 to 12 hours
  • Revenue lost per hour: $20k–$120k for small-to-midsize businesses
  • Brand damage: Measurable drop in user trust and retention after visible outages
  • Legal consequences: If service unavailability violates SLAs or regulatory standards

Conclusion: Protecting What Matters

In today’s interconnected world, availability is as important as functionality. A DDoS attack doesn’t just stop your app from working — it damages trust, reputation, and revenue. At Arpacore, we don’t wait for problems to occur. We build software — and infrastructure — with resilience in mind. If you're planning a launch, scaling an app, or simply want to know whether you're prepared, talk to us. We're here to help you build digital products that perform — even under pressure.