Tenable Nessus Network Monitor

Nessus Network Monitor is a passive sensor that continuously observes live network traffic. It discovers assets, services, and risk signals, helping you close visibility gaps without ever running intrusive active scans.

Quick Benefits

• Continuous Detection: Spot assets (including unmanaged devices) directly from real network traffic.
• Zero-Impact Monitoring: Gain visibility into sensitive networks without the disruption of active scanning.
• Deep Packet Inspection: Reveal hidden services and real-time exposure signals.
• Seamless Integration: Feed passive data directly into your broader Tenable platform for unified visibility.

Nessus Network Monitor At a Glance

• What it is: Passive network security monitoring that highlights new hosts, services, and interactive/encrypted sessions.
• Best For: Segmented networks, OT-like environments, and high-change areas where active scanning isn’t feasible.
• Licensing Model: Bundled entitlement (commonly included with Tenable Vulnerability Management or Tenable Security Center Continuous View).
• Activation: Enabled via the parent platform entitlement; deploy sensors as needed.
• Typical Terms: Quote-based, aligned to your parent Tenable platform subscription.

License Overview

A Nessus Network Monitor license enables passive monitoring as part of your broader vulnerability management program. Rather than being sold piecemeal, it is typically provided as a bundled component within Tenable Vulnerability Management or Tenable Security Center Continuous View.

How it works

Tenable’s licensing model allows you to deploy an unlimited number of passive sensors to monitor an unlimited number of networks. However, the total asset/IP visibility is constrained by the license tier of the parent management platform you purchased.

Deployment Strategy

This model is highly effective because you can scale sensors across data centers, branch offices, or restricted segments without incurring per-sensor fees. You reveal unmanaged devices and traffic-driven indicators without adding scanning load to sensitive segments. (Note: While currently branded as Tenable Network Monitor, planning simply requires aligning it with your existing TVM or Security Center setup).

Options & Tiers

For Nessus Network Monitor, the “tier” confusion is usually about where it is managed and how visibility is counted, not how many sensors you can install.

Features & Benefits

• Passive Network Detection: Discover hosts and services strictly from traffic, without impacting network performance. (Perfect for sensitive VLANs, OT segments, or congested links).
• Deep Packet Inspection: Understand exactly what is communicating and on which ports, providing deep service context. (Perfect for spotting rogue services on production networks).
• Continuous Change Detection: Track activity patterns over time and get alerts when new hosts appear. (Perfect for uncovering shadow IT and unmanaged devices).
• Platform Integration: Combine these passive insights with your broader Tenable coverage to unify discovery, assessment, and reporting.

Compatibility & Requirements

• Segmented networks (multiple VLANs/zones).
• Networks where active scanning is restricted or risky.
• Environments needing 24/7 asset visibility.

Quote Checklist

To get an accurate quote, please provide:

1. Management platform preference: Tenable Vulnerability Management (cloud) or Tenable Security Center (on-prem).
2. Number of network segments/sites to monitor.
3. Traffic visibility method (SPAN/TAP availability).
4. Primary reporting needs (asset discovery, change detection, service visibility).
5. Term preference for the parent subscription.

Activation Guide For Nessus Network Monitor

1. Choose Platform: Select your management console (TVM or Security Center).
2. Deploy: Install sensor(s) in the required network segments.
3. Feed Traffic: Route SPAN/TAP traffic to the sensors (monitoring only).
4. Verify: Confirm assets and services appear in your platform views (subject to your parent license limits).

Pricing Factors & Quoting

Pricing is not driven by the number of passive sensors you deploy. Instead, it relies entirely on your parent Tenable platform license and the visibility scope it enables (the asset view in Tenable Vulnerability Management or the IP view in Tenable Security Center Continuous View).