Inexhaustive list of network utilities. I hope you find it useful.
- arpwatch – keep track of ethernet/ip address pairings.
- bmon – bandwidth monitor and rate estimator.
- bwm-ng – console-based live network and disk io bandwidth monitor.
- curl – transfer data with URLs. (alternatives aria2, httpie)
- darkstat – Captures network traffic, calculates statistics, and serves reports over HTTP.
- dhclient – Dynamic Host Configuration Protocol Client.
- dhcpcd - RFC2131 compliant DHCP client daemon.
- dig – DNS lookup utility.
- dstat – A versatile resource statistics tool.
- ethtool – utility for controlling network drivers and hardware.
- gated – gateway routing daemon.
- host – DNS lookup utility.
- hping – TCP/IP packet assembler/analyzer.
- ibmonitor – shows bandwidth and total data transferred.
- ifstat – report network interfaces bandwidth.
- iftop – display bandwidth usage.
- ip (PDF file) – ifconfig on steroids.
- iperf3 – A TCP, UDP, and SCTP network bandwidth measurement tool.
- iproute2 – collection of utilities for controlling TCP/IP.
- iptables – utility for configuring Linux kernel firewall.
- IPTraf – Console-based network monitoring utility.
- iputils – Network monitoring tools, including ping.
- iw – a new nl80211 based CLI configuration utility for wireless devices.
- jwhois ( improved whois) – client for the whois service.
- “lsof -i” – reveal information about your network sockets.
- Lynis - Auditing, system hardening, compliance testing.
- mtr – network diagnostic tool.
- net-tools – the collection of base networking utilities for Linux.
- ncat – much-improved re-implementation of the venerable Netcat.
- nethogs – Linux 'net top' tool written in C++.
- Netperf – Network bandwidth benchmark.
- netsniff-ng – Swiss army knife for your daily Linux network plumbing if you will.
- netstat – Print network connections, routing tables, interface statistics, masquerade connections, etc.
- netwatch – monitor network connections.
- ngrep – ngrep is like GNU grep applied to the network layer.
- nload – Monitors network traffic and bandwidth usage.
- nmap – Nmap ("Network Mapper") utility for network discovery and security auditing.
- nmcli – command-line tool for controlling NetworkManager.
- nmtui – provides a text interface to configure networking by controlling NetworkManager.
- nslookup – for querying DNS to obtain domain name or IP address mapping. (alternatively dnslookup)
- openssl - The Open Source toolkit for SSL and TLS protocols.
- openvpn - robust and highly configurable VPN
- paping - TCP ping on specific port.
- ping – send icmp echo_request to network hosts.
- iproute2 (route) – show / manipulate the IP routing table.
- slurm – yet another network load monitor.
- snort – A lightweight network intrusion detection system.
- smokeping – A tool to keep track of your network latency.
- socat – relay for bidirectional data transfer between two independent data channels
- ss – another utility to investigate sockets.
- ssh – the infamous Secure Shell protocol.
- speedometer – Measure and display the rate of data across a network connection or data being stored in a file.
- speedtest-cli – for testing internet bandwidth using speedtest.net.
- systemd-networkd - a system daemon that manages network configurations.
- tcpdump – dump traffic on a network.
- tcptrack – displays information about TCP connections on a network interface.
- telnet – User interface to TELNET.
- tracepath – traces path to a network host discovering MTU along this path (similar traceroute)
- traceroute – Tracks the route taken by packets over an IP network.
- vnStat – A console-based network traffic monitor.
- websocat – CLI client for web sockets, like netcat/curl/socat for ws://
- wget – Network utility to retrieve files from the Web.
- WireGuard - extremely simple yet fast and modern VPN.
- wireless_tools – Tools allowing to manipulate the Wireless Extensions.
- Wireshark – network protocol analyzer.
Sorted alphabeatically, might make categories if the list expands significantly. You're welcome to make a pull request with suggestions.