Ettercap is a network sniffer/interceptor/logger for ethernet LANs. It supports active and passive dissection of many protocols (even ciphered ones, like SSH and HTTPS). Data injection in an established connection and filtering on the fly is also possible, keeping the connection synchronized. Many sniffing modes were implemented to give you a powerful and complete sniffing suite. Plugins are supported. It has the ability to check whether you are in a switched LAN or not, and to use OS fingerprints (active or passive) to let you know the geometry of the LAN.
GKrellM is a GTK-based stacked monitor program that charts SMP CPUs, disks, load, active net interfaces, and internet connections. There are also builtin monitors for memory and swap, file systems with mount/umount feature, mailbox checking including POP3 and IMAP, clock/calendar, laptop battery, sensors (temperatures, voltages, and fans), and uptime. It has LEDs for the net monitors and an on/off button and online timer for PPP. There is a GUI popup for configuration, plugin extensions can be installed, and many themes are available. It also features a client/server monitoring capability.
Nets is a flexible and extensible network inventory and asset management system that works on all Unix and Windows platforms, and works with most SQL databases. Its complete GUI allows you to maintain details of your entire network, from network links down to interfaces and routers. It assists in provisioning, costing, reporting, and maintaining network details. It includes a network browser, an extension API, and plugins for IP address map visualisation, reports, schematics.
pftp allows you to send and receive files and directories recursively, send and receive standard input and ouput, filter your connection, set the net buffer size, set the bandwidth, send UDP datagrams unicasted, broadcasted, and multicasted (which is meant for AUDIO and VIDEO streaming), send data to another user and manage that data, perform a network test based on either UDP or TCP, and use optimized buffers for your Gigabit Ethernet links. pftp can start from command line, as a daemon, or by inetd. All features are supported for IPv4 and IPv6.
netscript is a portable/multi-platform, lightweight TCP/UDP socket scripting system. It is intended to automate situations, built on a word-to-word ruleset response system. It includes wildcard support, character replacement, random replacement, argument inclusion, server timeout, initial send, display altering, multiple character dump formats, telnet protocol support, logging, program to socket dumping, executable ruleset support, reverse binding, module support, data truncation, data formatting, permission options, virtual hosting support, history storage, dynamic storage variables, directory placement, character omitting, timed rules, background support, syslog support, routing support, socket options, interactive mode, and graphical user interface support.
OpenVPN is a robust and highly configurable VPN (Virtual Private Network) daemon which can be used to securely link two or more private networks using an encrypted tunnel over the Internet. OpenVPN's principal strengths include wide cross-platform portability, excellent stability, support for dynamic IP addresses and NAT, adaptive link compression, single TCP/UDP port usage, a modular design that offloads most crypto tasks to the OpenSSL library, and relatively easy installation that in most cases doesn't require a special kernel module.
NetUP UTM is a universal billing system for internet service providers of any size. Its modern approach to traffic accounting makes the system compatible with all popular platforms and network devices. Its key features include realtime traffic processing, Cisco Netflow and IP Accounting data collection, support for RADIUS authentication, and cross-platform compatibility. The core of the system is a smart and reliable accounting engine working directly with network equipment. It supports up to 100,000 users at a total speed of up to 3 Gbps. A flexible ratings engine and efficient administration tools make UTM a complete solution for IP/VoIP/WiFi/dial-up billing.