MasarLabs PatD is a daemon to ping or traceroute remote hosts, using IPv4 or IPv6 ICMP packets. It runs without root privileges, listening on a TCP local port for hosts to check. It uses a protocol simple to implement, so is useful in situations in which you cannot send native ICMP packets (for example, from a Java program). pat is a client you can use to talk to patd.
Andrisoft WANSIGHT is a fully featured network traffic analyzer and collector. It provides in-depth traffic analysis, traffic accounting, and bandwidth monitoring, and enables you to generate complex traffic reports, graphs, and tops, instantly pin down the cause of network incidents, understand patterns in application performance, and make the right capacity planning decisions. It supports 10GbE packet sniffing and NetFlow, sFlow, and IPFIX.
dhcpy6d delivers IPv6 addresses for DHCPv6 clients, which can be identified by DUID, hostname, or MAC address, as in the good old IPv4 days. Addresses may be generated randomly, by range, or by arbitrary ID or MAC address. Clients can get more than one address, leases and client configuration can be stored in databases, and DNS can be updated dynamically.
ip2clue provides access to multiple databases (Maxmind, Software 77, Webhosting.info and ip2location) to retrieve country information associated with IP addresses. It has a daemon that supports lots of concurrent connections and a client binary. Some client examples are also provided in languages including PHP and C.
Suricata is an Intrusion Detection and Prevention (IDS/IPS) engine developed by the Open Information Security Foundation and its supporting vendors. The engine is multi-threaded and has native IPv6 support, file extraction capabilities, and many more features. It's capable of loading existing Snort rules and signatures, and supports many frontends through Barnyard2.
Borderline is a firewall generator. It takes a generic rule specification as input and generated an highly optimized firewall. It features IPv6 rule generation, support for multiple interfaces, and integrated support for network zones. It currently only supports firewall generation for Linux 2.6 (netfilter).
smtp-cli is an SMTP command line client with support for advanced features such as STARTTLS, SMTP-AUTH, or IPv6. It also has scriptable message composition capabilities supporting anything from simple plain-text messages right up to building complex HTML emails with alternative plain-text part, attachments, and inline images. It's also a convenient tool for testing and debugging SMTP servers' setups. smtp-cli can be used to check a given server's capabilities, to test your server's setup, or to create and dispatch email messages. The command line interface is intuitive, and everything is scriptable and can run in a completely non-interactive mode from scripts or cron jobs. smtp-cli is ideal for shipping log files from remote machines, running periodic mail delivery test loops, etc.