skd is a small daemon which binds to a UDP, TCP, or Unix-domain socket, waits for connections and runs a specified program to handle them. It is ideal as a secure, efficient replacement for traditional inetd. It is also an easy-to-use tool for non-privileged users wanting to run their own network services. Datagram and stream sockets are available in both the Internet and Unix namespaces, each with the expected inetd behavior. In the Internet domain, IPv6 is supported in addition to IPv4. skd also supports connection limits, verbose logging of connections, dropping of privileges, forking into the background with a pidfile, and redirecting stderr to syslog or a file. Some of these facilities (such as forking into the background, privilege dropping, and logging) are also useful for standalone, non-network services and can be used without binding any socket.
PumpKIN is a fully functional TFTP server and TFTP client that implements the TFTP protocol according to RFC1350. It also implements the block size option, which allows the transfer of files larger than 32MB, as well as transfer size and transfer timeout options described in RFC2348 and RFC2349.