wpa_gui is a nice GUI frontend for wpa_supplicant tool.
GNU Zebra is a free software (distributed under GNU Generic Public
License) which manages TCP/IP based routing protocols.
It supports BGP-4 protocol as described in RFC1771 (A Border Gateway
Protocol 4) and RIPv1, RIPv2 and OSPFv2.
Zebra uses multithread technology under multithread supported UNIX
kernels. However it can be run under not-multithread supported
UNIX kernels.
Zebra is intended to be used as a Route Server and a Route Reflector.
Zebra is not a toolkit, it provides full routing power under a new
architecture.
ZeroTier can be used for on-premise network virtualization, as a
peer to peer VPN for mobile teams, for hybrid or multi-data-center
cloud deployments, or just about anywhere else secure software
defined virtual networking is useful.
ZMap is a fast single packet network scanner designed for Internet-wide network
surveys. On a typical desktop computer with a gigabit Ethernet connection, ZMap
is capable scanning the entire public IPv4 address space in under 45 minutes.
With a 10gigE connection and PF_RING, ZMap can scan the IPv4 address space in
under 5 minutes.
zsync is a file transfer program. It allows you to download a file from
a remote web server, where you have a copy of an older version of the
file on your computer already. zsync downloads only the new parts of the
file. It uses the same algorithm as rsync.
zsync does not require any special server software or a shell account on
the remote system (rsync, in comparison, requires that you have an rsh
or ssh account, or that the remote system runs rsyncd). Instead, it uses
a control file - a .zsync file - that describes the file to be
downloaded and enables zsync to work out which blocks it needs. This
file can be created by the admin of the web server hosting the download,
and placed alongside the file to download - it is generated once, then
any downloaders with zsync can use it. Alternatively, anyone can
download the file, make a .zsync and provide it to other users (this is
what I am doing for the moment).
tcpdump is a ubiquitous network traffic capture tool available in a wide
variety of BSD, Linux and UN*X distributions.
Whilst FreeBSD has a vendor branch import of tcpdump in its source tree,
the purpose of the port is to provide a means of offering additional,
bleeding-edge features which might not make it into the tree.
tcpkali is a high performance load generator against TCP and WebSocket servers.
Tcpview is Motif-based TCP/IP protocol analyzer. It is a graphic version
counterpart of tcpdump(1). It allows users to analyze TCP/IP packets with
comfortable graphic interface.
A network analyzer that lets you capture and interactively browse the
contents of packets from a variety of network interface types. Packet data can
be read from a file, or live from a local network interface.
XORP is the eXtensible Open Router Platform.
The XORP project is developing an open source software router. The software
is intended to be stable and fully featured enough for production use, and
flexible and extensible enough for research use.