LanTopoLog
Map your network with automatic SNMP topology discovery
About LanTopoLog
LanTopoLog is a lightweight Windows and Linux application that automatically discovers and visualizes physical network topology using SNMP data from managed switches. It maps switch port connections to MAC and IP addresses, monitors device health and traffic, and alerts administrators to network changes and failures.
Pros & Cons
Pros
- Completely usable free version for core topology discovery
- Fast, lightweight, and portable with no system modifications required
- Affordable one-time perpetual license at $100 with free updates
- Accurate physical maps based on real SNMP switch port data
- Useful exports to PDF and Draw.io plus email/Telegram alerts
Cons
- License is bound to up to 3 specific switches, so replacing those switches can require a new license
- Windows/Linux desktop app rather than a modern cloud/web SaaS platform
- Interface is utilitarian and dated compared to enterprise NMS suites
- Relies entirely on SNMP, so unmanaged or non-SNMP devices won't be fully mapped
Key Features
Automatic Topology Discovery
Discovers physical network topology automatically via SNMP, drawing accurate maps based on real switch port data.
Switch Port Mapping
Maps each switch port to the connected MAC and IP addresses, with VLAN assignment and port status.
Searchable Network Maps
Provides detailed, searchable and editable topology maps showing which devices connect to each port.
New Device Detection
Auto-discovers and notifies you when new devices are added to the network.
Real-Time Monitoring
Monitors device state in real time using ICMP ping and tracks network traffic on switch ports.
Spanning Tree Alerts
Detects and alerts on Spanning Tree topology changes and invalid or dropped packets.
Notifications & Integrations
Sends alerts via email and Telegram, with Syslog integration for centralized logging.
Export & Inventory
Exports maps to PDF and Draw.io, and collects computer inventory data via WMI.
Pricing
- Physical topology discovery without limitations
- Network map visualization
- Some advanced features limited in demo mode
- Perpetual license (one-time payment)
- License bound to up to 3 switches
- Unlimited number of other switches
- Run on multiple computers simultaneously
- Free updates included
Best For
LAN Topology Visualization
Network administrators map their entire LAN automatically to see exactly which device sits on which switch port.
Troubleshooting & Fault Detection
Quickly locate connectivity issues, spanning tree changes, and dropped packets in real time.
Network Documentation
Export accurate, up-to-date topology diagrams to PDF or Draw.io for documentation and audits.
Device Inventory & Change Tracking
Detect new devices as they join the network and maintain an inventory of connected hosts.
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