Network Security Tools: A 10-Tool Guide to Scanning, Filtering, Packet Analysis and Monitoring

Buying one tool rarely solves network security, because attackers move across layers. A scanner finds weak spots, a filter blocks bad destinations, and a packet analyzer proves what happened.

This guide organizes ten SaaSPodium-listed products by the job they do, then shows how to combine them without overspending.

The Layers a Network Security Toolset Must Cover

A defensible network needs tools across five layers: prevention at the edge, visibility into traffic, vulnerability discovery, DNS and web filtering, and continuous monitoring. No single product covers all five well, so teams assemble a small stack and integrate it.

NIST's Cybersecurity Framework organizes this work into Govern, Identify, Protect, Detect, Respond and Recover. The tools below map mainly to Identify (scanning), Protect (filtering, firewalls) and Detect (packet analysis, monitoring).

• Prevent: network security platforms and firewalls that block malicious traffic.
• Inspect: packet analyzers that show what is on the wire.
• Find weaknesses: vulnerability scanners that list exposed services and missing patches.
• Filter: DNS and secure web gateways that stop users reaching malicious domains.
• Watch: monitoring platforms that alert on abnormal availability or traffic.

How We Picked These Network Security Tools

We selected ten products from five SaaSPodium categories (Network Security, Vulnerability Management, Network Analyzer, DNS Security and Network Monitoring) so the list covers each layer rather than ranking ten look-alike scanners. Ratings are not yet populated, so the picks reflect function, deployment model and company-size fit.

To prioritize spending, estimate risk reduction per dollar with a simple formula:

Annual loss exposure is your estimated yearly cost from incidents the tool addresses, and reduction percentage is the share you expect it to prevent or shorten. Treat the output as a ranking aid, not a prediction.

Trellix Network Security: Detection at the Network Edge

Trellix Network Security is a network detection and response product that inspects network traffic for advanced threats and known attack patterns, giving security operations teams alerts they can investigate and escalate. Trellix Network Security is the sole listing in SaaSPodium's Network Security Software category and uses custom pricing.

• Deployment: cloud, on-premises and hardware appliance options.
• Pricing model: custom quotes, so budget through a sales conversation.
• Best fit: mid-sized and large organizations with a security operations team to triage alerts.

Tenable.io: Risk-Based Vulnerability Management

Tenable.io scans assets for vulnerabilities and ranks them by risk so teams fix the most dangerous exposures first instead of working through thousands of low-impact findings in the order a scanner happens to list them. Tenable.io is a paid cloud platform.

• Architecture: cloud console with scanners and agents.
• Value: prioritization reduces the noise of long scan results.
• Best fit: teams that need asset-wide exposure tracking.

Qualys VMDR: Detection, Prioritization and Patching in One App

Qualys VMDR combines asset discovery, vulnerability detection and remediation workflows in a single cloud app, so security and IT teams work from the same asset list and the same prioritized queue of fixes. Qualys VMDR is a paid listing.

• Architecture: cloud platform using lightweight agents and network scanners.
• Coverage: discovery, scanning, prioritization and patch orchestration.
• Best fit: organizations that want one platform from discovery to fix.

Rapid7 InsightVM: Scanning Tied to Remediation Projects

Rapid7 InsightVM provides vulnerability scanning with dashboards and remediation tracking built for security and IT collaboration, so a finding can become an assigned remediation task with a due date and a measurable result. Rapid7 InsightVM is a paid listing.

• Architecture: console with scan engines and agents.
• Workflow: remediation projects and reporting help assign and track fixes.
• Best fit: security teams working closely with IT operations.

Greenbone Enterprise: OpenVAS Heritage With Commercial Support

Greenbone Enterprise brings the OpenVAS scanning engine into a supported commercial product with managed vulnerability test feeds, giving teams a lower-cost route to credible network vulnerability scanning with vendor backing. Greenbone Enterprise is a paid listing.

• Architecture: appliance and virtual deployment options, as well as the open-source community edition.
• Value: strong network vulnerability tests for budget-conscious teams.
• Best fit: organizations that value open-source roots with vendor support.

GFI LanGuard: Scanning and Patching for Smaller Networks

GFI LanGuard audits networks for vulnerabilities and missing patches and configuration weaknesses, and it can deploy fixes directly, so smaller teams can scan and remediate without buying two separate tools. GFI LanGuard is a paid listing in the Vulnerability Management category.

• Architecture: scanner with agent and agentless modes.
• Coverage: OS and third-party patching, vulnerability assessment and auditing.
• Best fit: small and mid-sized Windows networks.

Wireshark: The Standard Packet Analyzer

Wireshark is the open-source packet analyzer that network and security engineers use to inspect traffic at protocol level, whether they are tracing a slow application, investigating a suspicious host or verifying that encryption is actually in use. Wireshark is listed as open source and suitable for small, mid-sized and large teams.

• Capability: deep protocol dissection and filtering for investigations.
• Pricing model: free and open source.
• Limitations: it analyzes captures rather than prevents attacks, so pair it with preventive controls.

Cisco Umbrella: DNS-Layer Protection

Cisco Umbrella blocks malicious domains at the DNS layer before a connection is made, which helps stop phishing, malware downloads and command-and-control traffic for office and remote users alike. Cisco Umbrella is a paid cloud service for medium and enterprise teams.

• Architecture: cloud DNS resolution with policy controls.
• Value: protects roaming users without routing all traffic through a data center.
• Best fit: medium and large organizations with hybrid workforces.

Cloudflare Gateway: Zero Trust Web and DNS Filtering

Cloudflare Gateway filters DNS and web traffic as part of a zero trust platform, applying policy to what users and devices can reach on the internet regardless of where they are working. Cloudflare Gateway lists a starting price of $7 on SaaSPodium, so confirm current plans on the vendor site.

• Architecture: cloud-delivered secure web gateway and DNS filtering.
• Integration: works with identity providers for per-user policies.
• Best fit: medium and enterprise teams adopting zero trust.

PRTG Network Monitor: Availability and Traffic Visibility

PRTG monitors devices, bandwidth and services so unusual outages or traffic spikes show up quickly, which often signals an attack or a failing control. Paessler PRTG Network Monitor is listed as freemium.

• Architecture: core server with remote probes.
• Value: baseline-driven alerts on bandwidth and availability.
• Best fit: small and mid-sized teams that want monitoring alongside security tools.

Building Your Network Security Stack

Start with the cheapest controls that close the largest gaps: scan for vulnerabilities, filter DNS, and keep a packet analyzer ready for investigations. Add detection and response only when you have people to act on alerts.

1. Inventory assets and external exposure, then run authenticated vulnerability scans monthly and after major changes.
2. Apply DNS filtering to every user and device, including remote laptops.
3. Review firewall rules against NIST SP 800-41 Rev. 1 firewall guidelines, removing unused rules.
4. Use NIST SP 800-115 as a template for technical security testing.
5. Capture traffic with Wireshark when an alert needs protocol-level proof.

For more guidance read our best network security software comparison, the explainer on port scanners versus vulnerability scanners, and browse the Network Security Software category.

Frequently Asked Questions

What network security tools does a small business need first?
Start with a vulnerability scanner, DNS filtering and a firewall review. GFI LanGuard or Greenbone cover scanning, Cisco Umbrella or Cloudflare Gateway cover DNS filtering, and Wireshark is a free option for investigations. Add monitoring next.

How much do network security tools cost?
Pricing varies widely. Wireshark is free and open source, PRTG offers a freemium tier, Cloudflare Gateway lists a $7 starting price on SaaSPodium, and platforms like Trellix use custom quotes. Always confirm current pricing with each vendor.

Do I need both a vulnerability scanner and a packet analyzer?
Yes, they answer different questions. A scanner tells you what weaknesses exist before an attack, while a packet analyzer shows what actually crossed the network during an incident. Most mature teams keep both available.