Microsoft Network Monitor!

Wireshark is the world's foremost network protocol analyzer. It lets you capture and interactively browse the traffic running on a computer network. It is the de facto (and often de jure) standard across many industries and educational institutions.

Packet library for Windows. WinPcap is the standard tool for link-layer network access in the Windows environments: it can be used to capture and transmit raw network packets and has many useful advanced features, including kernel-level filtering, a network statistics engine and support for remote capture. WinPcap consists of a driver, that extends the operating system to provide low-level network access and a library that developers can use to easily access the low-level network layers.WinPcap is the industry-standard tool for link-layer network access in Windows environments: it allows applications to capture and transmit network packets bypassing the protocol stack, and has additional useful features, including kernel-level packet filtering, a network statistics engine and support for remote packet capture. »

An advanced, easy-to-use monitoring solution for your entire network. The software's features include: up/downtime monitoring, traffic and usage monitoring, packet sniffing, failover clustering, in-depth analysis and concise reporting. A user-friendly web-based interface allows users to quickly auto-discover and configure the network devices and sensors they wish to monitor. All common methods for acquiring network usage data are supported: SNMP and WMI, Packet Sniffing and NetFlow / sFlow / jFlow. It also offers SMTP/IMAP Roundtrip-Email Monitoring and VMware Monitoring, VoIP Monitoring, Toplists for Packet Sniffing and Netflow Sensors, as well as sensor aggregation using its built-in Sensor Factory. PRTG Network Monitor includes more than 200 sensor types for all common network services (e.g. PING, HTTP, SMTP, POP3, FTP, SSH etc.), allowing users to monitor networks for availability, speed and failures. As soon as an outage occurs, alerts are sent via email, SMS, pager messages and other means. Request times and downtimes are recorded in an internal database, making it easy to compile performance, downtime and SLA reports. Monitoring, reporting and notifications can be automatically scheduled at specific times. High Availabiltiy is guaranteed by the innovative failover cluster, and remote probes can be used for easy multi-location monitoring. Network maps can be created which provide users with a unique visual network management tool. PRTG Network Monitor's Freeware Edition is completely free for personal and commercial use. The Commercial Editions are required if you want to monitor more than ten sensors. »

Message Analyzer enables you to capture, display, and analyze protocol messaging traffic; and to trace and assess system events and other messages from Windows components.

SmartSniff is a packet sniffer that capture TCP/IP packets and display them as sequence of conversations between clients and servers. You can view the TCP/IP conversations in Ascii mode (for text-based protocols, like HTTP, SMTP, POP3 and FTP) or as hex dump (for non-text base protocols, like DNS). Application can capture TCP/IP packets on your network without installing a capture driver (works only for Windows 2000/XP or greater).

NetworkMiner is a Network Forensic Analysis Tool (NFAT) for Windows. NetworkMiner can be used as a passive network sniffer/packet capturing tool in order to detect operating systems, sessions, hostnames, open ports etc. without putting any traffic on the network. NetworkMiner can also parse PCAP files for off-line analysis and to regenerate/reassemble transmitted files and certificates from PCAP files.

Packetyzer provides a Windows user interface for the Ethereal packet capture and dissection library. Ethereal is used by network professionals around the world for troubleshooting, analysis, software and protocol development, and education. Ethereal has all of the standard features expected in a protocol analyzer, and several features not otherwise available.

Debookee is the simplest & most powerful network traffic analyzer for macOS.

Colasoft network packet sniffer or network analyzer software for Windows platform, sniff packets, monitor activities and analyze protocols, best tool for network monitoring and troubleshooting, Free trial available, download now.

iwScanner is a wireless scanner for linux with an easy to use graphic interface.

apptalk.ninja is a great, easy-to-use tool for app developers tackle that monitors and debugs issues with their apps’ communication over-the-air.

An url sniffer(HTTP, MMS, RTSP, RTMP) which provide one-step solution to finding the URLs for all streams.

TCPEye is an easy-to-use monitoring application that will display a list of all network processes. It sports all the features of "netstat" command and adds some options of its own as well as some third party online tools for IP tracing.

RawCap is a free command line sniffer for network activity on Windows.

LANGuardian is the first and only deep packet inspection (DPI) software to provide SMB network managers with root cause information about network and user activity. LANGuardian gives a deeper level of detail than standard flow tools, and is an affordable alternative to premium appliance based DPI tools.