SoftPerfect Network Protocol Analyzer

Free network sniffer for Windows

SoftPerfect Network Protocol Analyzer is a free professional tool for analysing, debugging, maintaining and monitoring local networks and Internet connections. It captures the data passing through the dial-up connection or Ethernet network card, analyses this data and then represents it in a readable form.

This is a useful tool for network administrators, security specialists, network application developers and anyone who needs a comprehensive picture of the traffic passing through their network connection or a segment of a local area network.

SoftPerfect Network Protocol Analyzer presents the results of its analysis in a convenient and easily understandable format. It can defragment and reassemble network packets into streams. The program also features full decoding and analysis of network traffic based on the following low-level Internet protocols: AH, ARP, ESP, ICMP, ICMPv6, IGMP, IP, IPv6, IPX, LLC, MSG, REVARP, RIP, SAP, SER, SNAP, SPX, TCP and UDP. It also performs a full reconstruction of top-level protocols such as HTTP, SMTP, POP, IMAP, FTP, TELNET and others.

The flexible system of fully-configurable filters can be used to discard all network traffic except for the specific traffic patterns you wish to analyse. There is also a packet builder, which allows you to build your own custom network packets and send them into the network. You could use the packet builder feature to check the network’s protection against attacks and intruders.

This is now a discontinued product. There will be no further updates or releases, however you can still download the last available version on this page, and continue using it for as long as you like. No support is provided for this software.

Key features

Decodes packets and displays them in an easy-to-read format.
Lets you build custom packets and send them into the network.
Works in promiscuous mode to capture all network packets.
Offers a flexible traffic filtering system. Any filter can be inclusive or exclusive.
Reconstructs packets into flows, so you can easily see a complete data exchange of the Telnet, POP3, SMTP, IMAP, FTP, HTTP and other protocols.
Monitors loopback connections within the system.