Paping (pronounced pah ping) is a computer network administration utility
used to test the reachability of a host on an Internet Protocol (TCP/IP)
network and to measure the time it takes to connect to a specified port.

redfishtool is a commandline tool that implements the client side
of the Redfish RESTful API for Data Center Hardware Management.

Find all open ports fast with RustScan, then automatically
pipe them into Nmap.

Scamper is a program that is able to conduct Internet measurement
tasks to large numbers of IPv4 and IPv6 addresses, in parallel, to
fill a specified packets-per-second rate. Currently, it supports the
well-known ping and traceroute techniques, as well as MDA traceroute,
alias resolution, some parts of tbit, sting, and neighbour discovery.

Scamper can do ICMP-based Path MTU discovery. scamper starts with the
outgoing interface's MTU and discovers the location of Path MTU
bottlenecks. scamper performs a PMTUD search when an ICMP
fragmentation required message is not returned to establish the PMTU
to the next point in the network, followed by a TTL limited search to
infer where the failure appears to occur.

ser2net provides a way for a user to connect from a network connection to a
serial port. It provides all the serial port setup, a configuration file to
configure the ports, a control login for modifying port parameters,
monitoring ports, and controlling ports.

The sethdlc utility is used to set physical interface, clock rate,
used HDLC mode, and can add any required PVCs if using Frame Relay.

https://www.kernel.org/doc/Documentation/networking/generic-hdlc.txt

Simple multicast Server/Client application.
Supports:

* IPv4 AND IPv6
* Multicast Server
* Multicast client
* Source Specific Multicast client

SNMP Simulator is a software that would act like a multitude of real
physical devices from SNMP Manager's point of view. Simulator builds
and uses a database of physical devices' SNMP footprints to respond
like their real counterparts do.

Typical use case for this software starts with recording a snapshot
of SNMP objects of donor agents into text files. Once you have your
snapshots at hand, a simulator script could be run over the snapshots
responding to SNMP queries in the same way as donor SNMP agents did
at the time of recording.

Technically, SNMP Simulator is a multi-context SNMP agent. That means
that it handles multiple sets of managed object all at once.
Each device is simulated within a dedicated SNMP context.

Simple SCEP (Simple Certificate Enrollment Protocol) client with
modifications for engine support & more.

A collection of various tools using ssh
The following tools are included
* ssh-ping: check if host is reachable using ssh_config
* ssh-version: shows version of the SSH server you are connecting to
* ssh-diff: diff a file over SSH
* ssh-facts: get some facts about the remote system
* ssh-hostkeys: prints server host keys in several formats
* ssh-keyinfo: prints keys in several formats
* ssh-certinfo: shows validity and information of SSH certificates

SSHamble simulates potential attack scenarios, including
unauthorized remote access due to unexpected state transitions,
remote command execution in post-session login implementations
and information leakage through unlimited high-speed authentication
requests.

The SSHamble interactive shell provides raw access to SSH requests in
the post-session (but pre-execution) environment, allowing for simple
esting of environment controls, signal processing, port forwarding,
and more.

Utility to test the performance of interactive ssh sessions or scp file
transfers. It uses ssh to log into a remote system, then runs two tests: the
first test sends one character at a time, waiting for each character to be
returned while it records the latency time for each. The second test sends a
dummy file over scp to /dev/null on the remote system.

TCPing will send TCP probes to an IP address or a hostname specified
by you and prints the result.
It works with both IPv4 and IPv6.

TCPING uses different TCP sequence numbering for successful and
unsuccessful probes, so that when you look at the results and spot
a failed probe, understanding the total packet drops to that point
would be illustrative enough.

* Monitor your network connection.
* Determine packet loss.
* Analyze the network's latency.
* Show min/avg/max probes latency.
* Use the -r flag to retry hostname resolution after a predetermined
number of ping failures. If you want to test your DNS load
balancing or Global Server Load Balancer (GSLB), you should
utilize this option..
* Print connection statistics on Enter key press.
* Display the longest encountered downtime and uptime duration and
time.
* Monitor and audit your peers network.
* Calculate the total uptime/downtime when conducting a maintenance.
* An alternative to ping in environments that ICMP is blocked.

A terminal UI for tshark, inspired by Wireshark.

testssl.sh is a free command line tool which checks a server's service on
any port for the support of TLS/SSL ciphers, protocols as well as some
cryptographic flaws.

A CLI tool that parses and manipulates URLs, designed to help
shell script authors everywhere.

TSCTP is an SCTP test tool. Its purpose is to perform basic SCTP
functionality tests to check implementations interoperability and
to verify that the SCTP stack is working.

uacme is a client for the ACMEv2 protocol described in RFC8555,
written in plain C code with minimal dependencies.
The ACMEv2 protocol allows a Certificate Authority and an
applicant to automate the process of verification and certificate
issuance. The protocol also provides facilities for other
certificate management functions, such as certificate revocation.

A simple curl wrapper which lets you use curl to download files
without having to remember any parameters.
Simply call wcurl with a list of URLs you want to download and
wcurl will pick sane defaults.

If you need anything more complex, you can provide any of curl's
supported parameters via the --curl-options option. Just beware
that you likely should be using curl directly if your use case is
not covered.

By default, wcurl will:
* Percent-encode whitespaces in URLs;
* Download multiple URLs in parallel if the installed curl's
version is >= 7.66.0;
* Follow redirects;
* Automatically choose a filename as output;
* Avoid overwriting files if the installed curl's version
is >= 7.83.0 (--no-clobber);
* Perform retries;
* Set the downloaded file timestamp to the value provided by the
server, if available;
* Disable curl's URL globbing parser so {} and [] characters in
URLs are not treated specially;
* Percent-decode the resulting filename;
* Use "index.html" as default filename if there's none in the
URL.

Command-line client for WebSockets, like netcat (or curl) for ws://
with advanced socat-like functions.

The Openconnect VPN server (ocserv) is an open source Linux SSL VPN server designed for organizations that require a remote access VPN with enterprise user management and control.