ntop!

Datadog is a monitoring service for IT, Dev & Ops teams who write and run applications at scale, and want to turn the massive amounts of data produced by their apps, tools and services into a unified view of IT infrastructure. Datadog's capabilities are provided on a SaaS-based data analytics platform that enables multiple teams to work collaboratively on infrastructure issues.

iftop does for network usage what top(1) does for CPU usage. It listens to network traffic on a named interface and displays a table of current bandwidth usage by pairs of hosts. Handy for answering the question "why is our ADSL link so slow?".

vnStat is a console-based network traffic monitor for Linux and BSD that keeps a log of network traffic for the selected interface(s). It uses the network interface statistics provided by the kernel as information source. This means that vnStat won't actually be sniffing any traffic and also ensures light use of system resources. However, in Linux at least a 2.2 series kernel is required.

Cacti is a complete frontend to RRDTool, it stores all of the necessary information to create graphs and populate them with data in a MySQL database. The frontend is completely PHP driven. Along with being able to maintain graphs, data sources, and Round Robin archives in a database, cacti handles the data gathering. There is also SNMP support for those used to creating traffic graphs with MRTG.

BandwidthD tracks usage of TCP/IP network subnets and builds html files with graphs to display utilization. Charts are built by individual IPs, and by default display utilization over 2 day, 8 day, 40 day, and 400 day periods. Furthermore, each ip address's utilization can be logged out at intervals of 3.3 minutes, 10 minutes, 1 hour or 12 hours in cdf format, or to a backend database server. HTTP, TCP, UDP, ICMP, VPN, and P2P traffic are color coded.

wavemon is a wireless device monitoring application that allows you to watch signal and noise levels, packet statistics, device configuration and network parameters of your wireless network hardware. It should work (though with varying features) with all devices supported by the Linux wireless kernel extensions by Jean Tourrilhes.

Diagnose network performance problems in real-time with Intermapper, network monitoring software from HelpSystems. Powerful, reliable, and user-friendly, Intermapper helps network professionals stay ahead of outages by monitoring the performance of all your physical and virtual equipment. Hundreds of probes built in to the product help you monitor all types of equipment from multiple vendors, and you can create your own or borrow probes from the user community to monitor additional gear. Features include auto-discovery, sophisticated network mapping, alerting, bandwidth monitoring, NetFlow analysis, flexible SNMP monitoring, and flow monitoring, all in one system. Intermapper also interfaces with Automate, IT and business process automation software from HelpSystems, to provide network remediation and self-healing. You can get started monitoring 10 devices for free, or download the free 30-day trial for 500 devices. »

darkstat is a packet sniffer which runs as a background process, captures network traffic, calculates statistics and serves them to a web browser.

Ethstatus is a console-based monitoring utility for displaying statistical data of the ethernet interface on a quantity basis. It is similar to iptraf but is meant to run as a permanent console task to monitor the network load.

iptraf-ng is a fork of original iptraf-3.0.0. IPTraf-ng is a console-based network monitoring utility. IPTraf-ng gathers data like TCP connection packet and byte counts, interface statistics and activity indicators, TCP/UDP traffic breakdowns, and LAN station packet and byte counts. IPTraf-ng features include an IP traffic monitor which shows TCP flag information, packet and byte counts, ICMP details, OSPF packet types, and oversized IP packet warnings; interface statistics showing IP, TCP, UDP, ICMP, non-IP and other IP packet counts, IP checksum errors, interface activity and packet size counts; a TCP and UDP service monitor showing counts of incoming and outgoing packets for common TCP and UDP application ports, a LAN statistics module that discovers active hosts and displays statistics about their activity; TCP, UDP and other protocol display filters so you can view just the traffic you want; logging; support for Ethernet, FDDI, ISDN, SLIP, PPP, and loopback interfaces; and utilization of the built-in raw socket interface of the Linux kernel, so it can be used on a wide variety of supported network cards. »

TrafShow continuously display the information regarding packet traffic on the configured network interface that match the boolean expression. It periodically sorts and updates this information. This funny program may be useful for locating suspicious network traffic on the net or to evaluate current utilization of the network interface.

LiveMon is a cloud-based monitoring software designed for IT teams, Dev-ops, CIOs, and Infrastructure & Application Directors. The Artificial Intelligence detects incoming IT performance incidents before they actually harm your business services. You prevent fires rather than fighting them. With unlimited scalability, you can monitor all types of environments from one server to over 100,000 severs with heterogeneous application sets to get a unified view of all the interactions, performance KPIs and data patterns. LiveMon will help you detect and solve any anomalies, optimize your infrastructure utilization, and correlate events. Packaging server monitoring and web-performance monitoring along with log analysis and storage, LiveMon is the only SaaS solution that gives you real-time 360° end-to-end visibility of your Information System. Thanks to LiveMon you no longer have to waste valuable time digging into your IT to find the right information, everything is visible in a single glance. »

Founded on the base of deep knowledge and experience in network optimisation, Sinefa is shaping the way network visibility and control will look in the future.

BLËSK is a suite of applications for network monitoring and management. It is comprised of a mix of open source and proprietary tools that come pre-installed and configured on an optimized 64-bit version of CentOS Linux. BLËSK helps people see and understand the behaviour of their network. Anyone can quickly visualize, analyze, and pinpoint problems when they occur.