computer
Computer Network
Learn networking fundamentals, devices, protocols, IP, DNS, routing and troubleshooting.
REFERENCE Β· 26 ITEMS
Computer Network
Networking from home Wi-Fi to IP, DNS, routing and troubleshooting.
26 items across 4 sections
COMPLETE COURSE
Computer Network β Learning Path
Start with the concept, study each lesson, copy and adapt the example, complete the practice task, then use the troubleshooting and safety notes before moving forward.
Module 01 β Fundamentals
What you learn: LAN/WAN, MAC, IP, subnet, gateway, DNS, DHCP.
Module 02 β Devices
What you learn: Router, switch, access point, modem, firewall.
Module 03 β Protocols
What you learn: Ethernet, ARP, ICMP, TCP, UDP, HTTP/HTTPS, SSH, DNS.
Module 04 β Troubleshooting
What you learn: ipconfig/ifconfig, ping, tracert, nslookup/dig, route, port checks.
SECTION
Fundamentals
LAN/WAN, MAC, IP, subnet, gateway, DNS, DHCP
LAN/WAN
LAN/WAN: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study LAN/WAN in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
LAN/WANMAC
MAC: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study MAC in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
MACIP
Linux command IP: a practical CLI building block. Use it in a terminal, review the output before changing files or services, and check IP --help for supported options. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study IP in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
IPsubnet
subnet: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study subnet in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
subnetgateway
gateway: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study gateway in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
gatewayDNS
DNS: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study DNS in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
DNSDHCP
DHCP: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study DHCP in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
DHCPSECTION
Devices
Router, switch, access point, modem, firewall
Router
Router: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study Router in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
Routerswitch
switch: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study switch in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
switchaccess point
access point: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study access point in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
access pointmodem
modem: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study modem in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
modemfirewall
firewall: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study firewall in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
firewallSECTION
Protocols
Ethernet, ARP, ICMP, TCP, UDP, HTTP/HTTPS, SSH, DNS
Ethernet
Ethernet: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study Ethernet in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
EthernetARP
ARP: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study ARP in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
ARPICMP
ICMP: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study ICMP in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
ICMPTCP
TCP: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study TCP in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
TCPUDP
UDP: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study UDP in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
UDPHTTP/HTTPS
HTTP/HTTPS: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study HTTP/HTTPS in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
HTTP/HTTPSSSH
Linux command SSH: a practical CLI building block. Use it in a terminal, review the output before changing files or services, and check SSH --help for supported options. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study SSH in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
SSHDNS
DNS: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study DNS in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
DNSSECTION
Troubleshooting
ipconfig/ifconfig, ping, tracert, nslookup/dig, route, port checks
ipconfig/ifconfig
ipconfig/ifconfig: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study ipconfig/ifconfig in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
ipconfig/ifconfigping
Linux command ping: a practical CLI building block. Use it in a terminal, review the output before changing files or services, and check ping --help for supported options. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study ping in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
ping -c 4 example.comtracert
Windows command tracert: run it from Command Prompt with the required permissions. Test read-only commands first and use tracert /? when available for syntax. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study tracert in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
tracertnslookup/dig
nslookup/dig: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study nslookup/dig in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
nslookup/digroute
route: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study route in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
routeport checks
port checks: a practical computer skill. Learn the purpose, core concept, syntax or workflow, real-world use cases, prerequisites, common mistakes, troubleshooting path, security implications, and related advanced concepts. Start with a safe read-only example, verify the result, then move to automation or administration only when you understand the side effects. Computer Network: follow the path from physical/link connectivity through IP, DNS, transport ports, TLS and the application. Troubleshoot one layer at a time. Study port checks in four passes: (1) purpose and vocabulary, (2) mechanism or syntax, (3) a safe practical example, and (4) verification plus troubleshooting. For every exercise, record the starting state, action, expected result, actual result and recovery step. This turns memorization into a repeatable professional workflow.
port checks