Fundamentals Networking and Security Tools

Ping

  • Ping stands for Packet InterNet Groper.

  • A networking utility - used to test whether a host is alive on an Internet Protocol (IP) network.

  • Ping sends an ICMP echo request to the target and waits for a reply.

  • Things it reports:

    • problems (if there was an error in reaching the host)

    • Trip time (how long it took to reach the host and come back)

    • Packet loss

When to use this tool?:

  • If you are experiencing network difficulties, this is the first tool to pull put of your toolkit.

Tip: if you want to check the name of your host, then ping yourself as ping ping -a 127.0.0.1.

Get help:

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IPConfig

The command ipconfig is usually the next tool you will pull out of your toolbox if you're networking a system.

  • Internet Protocol is a set of rules that govern how data is sent over the Internet or another network.

  • IP has the function of taking packets from the source host and delivering them to the proper destination host solely based on the IP add in a packet.

With this command you can answer lots of questions:

  • Which adapters (Ethernet or Wi-Fi or Bluetooth or Virtual network) are connected with an IP address?

  • Which ones are disconnected?

Dynamic Host Configuration Protocol (DHCP)

DHCP is a network management tool. This is the tool that dynamically assigns an IP address to a host on a network. Most likely, a router or a gateway can be used to act as a DHCP server.

Here are two commands for you to use if you want to a new IP address:

  • ipconfig /release : This releases all IPv4 addresses

  • ipconfig /renew : This retrieves a new IP address, which may take a few moments

Domain Name System (DNS)

This is a naming system for all hosts that are connected to the internet or your private network. So what you do on the Internet or in a private network, DNS will remember domain names. It will store this data in cache - just to speed up the subsequent requests to the same host.

Note: Cache Poisoning - sometimes called DNS spoofing - is an attack where a malicious party corrupts the DNS case or table, causing the nameserver to return an incorrect IP address and network traffic to be diverted.

Here are two more commands to try:

  • ipconfig /displaydns: This may scroll for a while because this is a record of all the domain names and their IP addresses you may have visited on a host.

  • ipconfig /flushdns : if you start encountering HTML 404 error codes, you may need to flush your cache clean. This will force your host to query nameserver for the latest and greatest info.