Secure Your Network with AWS NACL & Access Control Solutions

Enterprise-Grade Cybersecurity for the Mid-Market

The problem: Many startups and mid-sized companies move to AWS for agility but postpone “deep” network security until later. Unfortunately, later often arrives after the first penetration test—or breach.

The solution: AWS NACLs let you shrink your attack surface on day one. Because NACL rules apply at the subnet level, they provide a first-hop firewall that catches unwanted traffic before it can even knock on your EC2 instance’s door. Pair them with Security Groups, AWS Firewall Manager, and modern observability tools and you’ve built layered protection without buying exotic hardware or hiring a full security operations center.

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Our Services at a Glance

We need guardrails fast, but we’re short on staff.

Rapid NACL Baseline: We deploy a least-privilege rule set tailored to your VPC architecture in days, not weeks.

Our auditors want proof the controls work.

NACL Validation & Reporting: Continuous monitoring and evidence collection mapped to CIS AWS Foundations and ISO 27001 controls.

Every sprint spins up new subnets.

Automated Guardrails: Our CI/CD hooks ensure every new subnet inherits approved NACL templates automatically.

We’re outgrowing a one-person IT team.

vCISO Program: Fractional security leadership to formalize policy, incident response, and compliance without a six-figure payroll hit.

Understanding AWS Network Access Control List

What Is an AWS NACL?

Think of a NACL as a stateless, subnet-level firewall. Each VPC subnet can be associated with exactly one NACL, and each NACL contains numbered rules that either allow or deny traffic based on protocol, port, and CIDR. Because the rules are stateless, return traffic must be explicitly allowed in both directions.

How Does a NACL Work in AWS?

  • Packet enters subnet → AWS evaluates the NACL rules in ascending order.
  • First match wins → If Rule 100 allows TCP 443 inbound from 0.0.0.0/0, the packet passes; if Rule 110 denies the same, the deny never triggers because Rule 100 matched first.
  • Default deny → Any traffic that fails to match an allow rule is implicitly dropped.

NACL vs. Security Groups

Quick rule of thumb: Use Security Groups to define who can talk to an instance; use NACLs to define whether that subnet should ever see that traffic at all.

When to Use AWS Network Access Control Lists

  • Public-facing apps with strict IP allowances
  • Isolating dev/test environments
  • Rapid quarantine
  • Compliance segmentation

Understanding AWS Network Access Control List

What Is an AWS NACL?

Think of a NACL as a stateless, subnet-level firewall. Each VPC subnet can be associated with exactly one NACL, and each NACL contains numbered rules that either allow or deny traffic based on protocol, port, and CIDR. Because the rules are stateless, return traffic must be explicitly allowed in both directions.

How Does a NACL Work in AWS?

  • Packet enters subnet → AWS evaluates the NACL rules in ascending order.
  • First match wins → If Rule 100 allows TCP 443 inbound from 0.0.0.0/0, the packet passes; if Rule 110 denies the same, the deny never triggers because Rule 100 matched first.
  • Default deny → Any traffic that fails to match an allow rule is implicitly dropped.

NACL vs. Security Groups

Quick rule of thumb: Use Security Groups to define who can talk to an instance; use NACLs to define whether that subnet should ever see that traffic at all.

When to Use AWS Network Access Control Lists

  • Public-facing apps with strict IP allowances
  • Isolating dev/test environments
  • Rapid quarantine
  • Compliance segmentation

Why SideChannel Cyber Is Built for Startups and SMBs

Most managed-security providers were designed for Fortune 500 budgets. We weren’t. Our delivery model assumes lean teams, fast release cycles, and the reality that tomorrow’s sprint can’t wait six weeks for a change-control board.

Security Leadership Without Full-Time Executive Cost

Hiring a full-time CISO averages $250k+ per year in the U.S. Our virtual CISO service costs a fraction of that, giving you senior guidance on strategy, risk, and board-level reporting—plus hands-on NACL and Security Group design reviews.

Streamlined Compliance with RealCISO and Enclave

RealCISO — With evidence collection against common control frameworks, RealCISO allows you to map your AWS network-based controls directly to frameworks like NIST 800-53, SOC 2, NIST-CSF, CIS and more. Instead of wrestling with spreadsheets, your team gets real-time dashboards showing control coverage, pending gaps, and audit-ready reports—all with less manual effort and fewer surprises at assessment time.

Enclave — Integrated capabilities of vulnerability management, certificate management, secure web gateway, micro segmentation shrink your attack surface and simplify compliance. Enclave’s micro segmentation enforces least-privilege access by default, while certificate management keeps device authentication strong and audit-ready. Continuous vulnerability scans feed risk scores into compliance dashboards, and the secure web gateway ensures policy-aligned internet use—creating a closed loop of visibility, enforcement, and proof for regulators.

Ready to Shrink Your Attack Surface? Whether you need a one-time NACL health check, a full segmented VPC redesign, or white-glove compliance support, we’re here to help. Book a free 30-minute consult and see how quickly the right access-control strategy can turn “cloud chaos” into “cloud confidence.”

What We Offer

At SideChannel, we believe in a collaborative approach. Our team works closely with your internal staff to understand your unique challenges and objectives. This partnership allows us to provide customized solutions that integrate seamlessly with your existing processes and infrastructure.

Advisement on all forms of cyber risk and how to address them

Coaching for your board, management team, and security team

Vendor product and service evaluation and selection

Maturity modeling operations and engineering team processes, capability, and skills

Board and management team briefings and updates

Operating and Capital budget planning and review

Finding the right Cyber insurance policy to protect your businesses and employees

Leading your organization through an incident or breach.

— CIO, Publicly Traded BioTech

Partnering with SideChannel’s vCISO services was a game-changer for our organization. Their expertise and tailored approach transformed our cybersecurity posture, turning our vulnerabilities into strengths. We’ve not only enhanced our defenses but also streamlined our processes, making security a seamless part of our daily operations. The impact on our organization’s security and overall confidence in facing digital threats has been remarkable.

— GC, FinTech Company

Working with SideChannel’s vCISO services brought a level of cybersecurity expertise to our company that we couldn’t have achieved on our own. Their team didn’t just address our immediate security concerns; they provided a strategic, long-term vision that has fundamentally strengthened our organization’s resilience against cyber threats. It’s been an invaluable partnership, elevating our security infrastructure and instilling a robust culture of cybersecurity awareness throughout our team.

— CTO, Integrated Marketing Agency

Working with SideChannel, it was great to have a guide to explain the significance of the steps of what the grade and the goal of each. The guidance offered what needed to get done, and in what order, couched with ‘hey, some of these things are complex, some of these things take longer, some of these things are more critical. It felt very bespoke and that’s something that you only get with a specialist and I just think it’s fantastic.

— Shane Winegard (CIO, Panduit)

Our SideChannel vCISO is an integral member of our executive team. He understands our unique challenges, the evolving security landscape, and best of breed technologies. Now we have a trusted advisor who has improved our security posture in a measurable way.

— CTO, Integrated Marketing Agency

I’m not a particularly patient guy, but I’ve never had an instance where I felt like I was waiting on SideChannel.

Get Started with SideChannel

Ready to take your cybersecurity to the next level? Contact us today to learn more about how SideChannel can help you achieve your cybersecurity goals with our engineering services.

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SideChannel vCISO Services

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SideChannel
Proud Member of

Worcester Regional Logo

© 2025 SideChannel, Inc. All rights reserved. | “SideChannel” and logo are registered trademarks of SideChannel, Inc.