FREE Network Protocol Analyzer and Packet Data Sniffer

Free Network Analyzer Overview

Free Network Protocol Analyzer Screenshot

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Free Network Analyzer is a non-intrusive software network packet sniffer and real-time network protocol analyzer for Windows platform.

It provides you with on-the-fly network traffic capture, protocol parsing and packet inspection functionality. Thanks to highly optimized and carefully tuned algorithms, our software network analyzer turns raw data into readable forms online, even at high data rates. It features sniffing of live connections and processes data on the fly without interfering with monitored communication. In contrast to competing products, network protocol parsing and structure binding functionality works instantly and keeps system performance intact. Product remains responsive when monitoring 1Gbps network links, even on a budget desktop PC. Its superior performance makes this network protocol analyser extremely useful for real-time network monitoring and data logging applications.

It can capture network traffic on Windows 10, Windows 11 and supports all desktop/server Windows platforms (both 32-bit and 64-bit) starting from Windows Vista.

Free Network Analyzer Basic Features

This free network sniffer supports basic functions for simple network protocol analysis, as well as for troubleshooting, securing and maintaining network infrastructures. It allows you to capture network packets passed through your network adapters or interfaces. Freeware version offers you a variety of network protocol analysis features, including the following: deep inspection of major network protocols, protocol-based network data filtering, browsing captured data, searching for specific data patterns with RegEx (Regular Expressions) support, network data logging (real-time network data logger feature), importing external WinPcap log files from different protocol analyzers and more. Analyzing network protocols made easy.

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Network Protocol Analyzer Extended Features

This is a Freemium product, so it’s basic network packet sniffing tools are free, while access to the advanced features requires payment. The paid version of packet sniffer also includes additional features for in-depth network applications and devices analysis. It allows you to replay previously recorded log files (saved with a data recorder), export text and raw data and even create custom views for any type of captured data, provides network data graphical analysis (statistics). Additionally, it includes network packet builder with capability of sending packets to the adapter and supports automating product functions using scripts (JavaScript/TypeScript).

Extended version also includes advanced software MODBUS sniffer and TCP MODBUS device simulator that parses MODBUS protocol commands (MODBUS RTU/ACSII) and allows you to send MODBUS TCP/IP requests in response to triggered events (useful for debugging a MODBUS-compatible device).

Download this Windows packet sniffing tool and monitor network packets the easy way!

How Free Network Analyzer Works

Free network protocol analyzer installs a filter driver in the NDIS (Network Driver Interface Specification) driver stack and then captures network traffic passing through the NIC (Network Interface Controller). This allows you to intercept all data frames starting from the Data Link Layer - Layer 2 of OSI (Open Systems Interconnection) model.

To overcome IEEE 802.3 Ethernet frame size restrictions, we support jumbo frames, which are widely used, for example, in PPPoE networks.

For each running monitoring session, a corresponding session is created within the filter driver, and the captured data is stored in a buffer until the application picks it up. Transport layer packets (e.g. TCP or UDP packets) are associated with processes running in the operating system, their PIDs and names are shown to the user, facilitating the network data analysis.

All network data extracted from filter driver is sent to the program for subsequent processing. Then application parses the captured data by binding different structures (defined in C-like structure definition .h-files) to certain packet offsets.

That’s the way network packets are parsed on the Data Link Layer (ARP, PPP, Ethernet packets), Network Layer (IPv6, IPv4 packets), Transport layer (TCP, UDP), Session Layer, Presentation Layer and Application Layer. So, using this software netanalyzer you always get a complete packet trace over the full depth of the encapsulated protocols.

Download this net sniffer now and start tracing network packets in seconds!

View network protocols supported by our networksniffer

Our LAN/Internet packet sniffer supports parsing of data transmitted over the following network protocols:

UDP - User Datagram Protocol
TCP - Transmission Control Protocol
IP - Internet Protocol
HTTP - Hyper Text Transfer Protocol
HTTPS - Hypertext Transfer Protocol Secure
FTP - File Transfer Protocol
SSL - Secure Sockets Layer Protocol
DNS - Domain Name System Protocol
NetBIOS, NBNS, NBSS - Network Basic Input Output System
NetBIOS over TCP/IP Protocol (NBT)
BACNET - Building Automation Control Network
PPP - Point-to-Point Protocol
PPPoE - Point-to-Point Protocol over Ethernet
PPTP - Point-to-Point Tunneling Protocol
Modbus/TCP - Modbus TCP Protocol
SMB - Server Message Block Protocol
SMB2 - Server Message Block Protocol v2
SMB over TCP
IPV4 -Internet Protocol version 4
IPV6 - Internet Protocol version 6
TLS - Transport Layer Security Protocol
WINS - Windows Internet Name Service Protocol
DHCP - Dynamic Host Configuration Protocol (ipv4)
DHCPv6 - Dynamic Host Configuration Protocol (ipv6)
SMTP - Simple Mail Transfer Protocol
IMAP - Internet Message Access Protocol
NetLogon, Kerberos - Computer network authentication protocol
LLDP - Link Layer Discovery Protocol
LCP - Link Control Protocol
LLC - Local link control Protocol
ATM - Asynchronous Transfer Mode Protocol
ARP - Address Resolution Protocol
CCP - Compression Control Protocol for PPP
CHAP - Challenge Handshake Authentication Protocol
EAP - Extensible Authentication Protocol
GRE - Generic Routing Encapsulation
IPX - Internet Packet Exchange Protocol
IPCP - IP Control Protocol
IPCPv6 - v6 version
ICMP - Internet Control Message Protocol
ICMPv6 - v6 version
LLMNR - Link Local Multicast Name Resolution Protocol
LQR - Link Quality Report Protocol
SIP - Session Initiation Protocol
MIME - Multi-purpose Internet Mail Extensions Protocol
MSPRC - Microsoft Remote Procedure Call Protocol
RPC - Remote Procedure Call Protocol
SNA -Systems Network Architecture Protocol
SNMP - Simple Network Management Protocol

Download this tcp/ip packet sniffer and udp analyzer - trace network packets in seconds!

View network analyzer usage scenarios

Free Network Analyzer Usage Scenarios

With our freeware net analyzer you can:

Capture TCP/IP packets that pass through the network adapter
Parse and decode LAN/Internet packets for deep network analytics
Analyze network problems and verify system effectiveness
Detect, explore and trace network security threats, generate network traffic for penetration testing
Identify, analyze and track network anomalies, detect and isolate malware
Use this Ethernet packet sniffer/analyzer for network forensics and analysis
Collect and analyze data flow from network devices, routers and switches (hubs)
Analyze network configuration (interfaces, adapters, ports, parameters)
Gather baseline traffic patterns and network-utilization metrics
View Winsock calls, WINS Queries , DNS Queries, DHCP information
Search for specific text strings, binary/decimal and hex data patterns in monitored network packets
Reverse engineer network applications and network communication protocols
Use this packet tracer to analyze Lan and Internet connections
View, test and troubleshoot client - server communications
Test and debug network protocol implementation
Use this Windows packet sniffer to detect malicious local network and Internet traffic

If you need efficient software-based development and debugging solution for you network applications, devices/drivers, our free network packet analyzer is exactly what you are looking for. This network traffic analysis software requires no additional hardware and allows you to test network communications, debug protocol errors, view and fix network issues.

Download this tcp/ip packet sniffing utility and start sniffing your network connection in seconds.

System Requirements and OS support

Free network protocol analyzer software requires 2 GB of RAM and 256 MB of free hard disk space. This free network monitor allows sniffing network packets on the x86 and x64 Windows platforms starting from Windows Vista (x86, x64) and supports both desktop and server systems, including Windows 10, Windows 11 and Windows Server 2022.

Download it now. Monitor, log and analyze your network dataflow, it’s FREE.