Table of Contents
Introduction
Organizations are increasingly adopting multi-homed network architectures to ensure business continuity and meet regulatory requirements. However, this approach introduces unique challenges for DDoS protection that many organizations overlook until it’s too late.
Understanding Multi-Homed: Beyond Basic Redundancy
Being multi-homed occurs when an organization maintains connectivity through multiple Internet service providers. While this approach provides essential redundancy and can offer performance benefits, it creates a complex security landscape that requires careful consideration.
Why do enterprises choose multihomed architectures?
Regulatory Requirements: Many industries, particularly those in finance and critical infrastructure, face government mandates that require redundant connectivity paths. These regulations recognize that single points of failure can have catastrophic consequences.
Business Resilience: Even without regulatory pressure, organizations understand that if a primary Internet provider experiences downtime, business operations must continue seamlessly. Multihomed connectivity provides this insurance policy.
Performance Optimization: Organizations can distribute workloads across providers, potentially accessing different geographical regions or optimizing for specific performance characteristics.
Geographic Distribution: Different providers may offer superior performance or coverage in different regions, making multihomed architectures a strategic business decision.
The Hidden Challenge in Protecting Multiple Attack Surfaces
Here’s where many organizations stumble: while they’ve solved the availability challenge, they’ve inadvertently created a security gap. When you have multiple Internet connections, you potentially have multiple attack vectors that need protection.
Consider this scenario: Your primary ISP provides excellent DDoS protection as part of its service package, but your secondary provider offers only basic connectivity. What happens when attackers target your unprotected link? The result can be a significant business impact, including:
- Service degradation or complete outages affecting employee productivity
- Customer access issues are impacting revenue and satisfaction
- Brand reputation damage from perceived unreliability
- Lost revenue during attack periods
The challenge extends beyond just having two problems instead of one. Organizations often face operational complexity in managing different protection services, potentially with varying interfaces and response procedures across providers.
Strategic Approaches to Multi-Homed DDoS Protection
The Layered Defense Strategy
The most effective approach remains defense in depth by implementing protection across multiple layers of your infrastructure. This strategy begins with an on-premises deployment that can handle ingress traffic from both circuits simultaneously.
Why start on premises? Consider this critical statistic: 82% of DDoS attacks today are less than one gigabit per second. If your Internet connection capacity exceeds one gigabyte, your ISP’s volumetric protection may not even activate for these smaller attacks. These “sub-threshold” attacks can still cause significant service disruption, making on-premises protection essential.
Handling Volumetric Attacks
For larger, volumetric attacks that threaten to overwhelm your connection capacity, organizations have two primary strategies:
Route Withdrawal Approach: When under attack, stop announcing routes for the unprotected link, forcing all traffic through your protected provider. While effective, this approach may not be suitable for all organizations due to regulatory requirements or business policies that require the active use of both links.
Cloud-Based Redirection: Deploy cloud-based protection that can redirect traffic from the unprotected link through a scrubbing service when needed. The key is to use this approach “when needed” rather than always-on, to minimize latency and costs.
Minimizing False Positives
Let’s address the elephant in the room: no DDoS protection solution can guarantee zero false positives. Anyone claiming otherwise isn’t being entirely truthful. However, you can minimize false positives through:
- Advanced analytics that examine traffic through multiple classification methods
- Consolidated analysis that prevents double-counting legitimate traffic across different links
- Technology that can differentiate between legitimate traffic on one circuit and malicious traffic on another
Guidance for Service Providers: Turning Challenges into Opportunities
Service providers have a unique opportunity to differentiate themselves by proactively addressing multihoming challenges. Rather than viewing customer multi-homed architectures as a limitation, consider it a business development opportunity.
The Conversation Starter
When you know a customer is multi-homed, initiate conversations about their complete protection strategy. Ask questions like:
- “How are you protecting your third-party link?”
- “Can we help you deploy an on-premises solution that integrates with both providers?”
- “What technology does your other provider use, and how can we ensure compatibility?”
Building Credibility and Revenue
By helping customers address their multi-homed protection gaps, you:
- Demonstrate comprehensive security expertise beyond just your own network
- Build stronger customer relationships through proactive problem-solving
- Create expansion opportunities within existing accounts
- Differentiate your connectivity services through enhanced security value
Technology Integration and Performance Considerations
Organizations often worry about performance impact when implementing inline protection solutions. The reality is that performance impact depends entirely on the technology you choose. Modern, sub-second mitigation solutions can provide comprehensive protection without introducing latency or throughput limitations.
The key is ensuring your protection technology can:
- Work with existing infrastructure, including current router configurations
- Support BGP flowspec for automated mitigation integration
- Integrate with cloud providers for scalable volumetric protection
- Provide unified management across all protection layers
Our Holistic Approach
At Corero, we address multihomed challenges through comprehensive solutions deployable at multiple architectural layers:
Edge Protection: Safeguarding traffic entering service provider networks.
Core Network Protection: Defending against attacks within the provider’s infrastructure
On-Premises Granular Protection: Catching sophisticated Layer 3 and Layer 7 attacks that bypass upstream filtering.
Unified Management: Single dashboard visibility across all attack surfaces and protection layers
Additionally, our platform includes business intelligence tools that help service providers identify prospective customers within their networks who may be vulnerable to attacks but lack adequate protection—turning security insights into business opportunities.
Key Recommendations
For Enterprises
- Don’t take ISP protection claims at face value. Understand exactly what technology they use, response times, and performance implications.
- Ask about integration capabilities. How will their protection work with your existing router infrastructure and any on-premises solutions?
- Plan for the complete attack surface. Ensure every Internet connection has appropriate protection, not just your primary link.
For Service Providers
- Differentiate through comprehensive security. Don’t just offer connectivity; provide highly resilient, filtered connectivity that keeps customers up and running.
- Don’t dismiss on-premises solutions. They complement, rather than compete with, your network-based protection, creating a comprehensive security solution.
- Proactively address multihomed architectures. Use customer multi-homed setups as an opportunity to demonstrate value and expand relationships.
Conclusion
Multi-homed architectures are no longer optional for many organizations; they’re a business necessity driven by regulatory requirements, operational resilience needs, and performance optimization goals. However, the security implications of multiple Internet connections require careful planning and comprehensive protection strategies.
The organizations that thrive are those that view multihomed protection not as a burden, but as an opportunity to build more resilient, secure, and high-performing network architectures. By implementing layered defense strategies, selecting the right technology partners, and maintaining open communication between enterprises and their service providers, we can transform multihomed architectures from a security challenge into a competitive advantage.
For more information about comprehensive DDoS protection strategies for multi-homed environments, speak with one of our specialists.
