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Network Utilities-
 ifconfig, traceroute, netstat, ping, arp

 

1. ifconfig stands for “interface configuration”. It is used to view and change the configuration of the network interfaces on your system.
Options :
  • a : view the configuration of all network interfaces on the system. 
  • eth0 : view the configuration of a specific interface, specify its name
    as an option.
  • wlan0 down : disable an active network interface using
    the down keyword.

2. Traceroute attempts to trace the route an IP packet would follow to some Internet host by launching probe packets with a small ttl (time to live) then listening for an ICMP “time exceeded” reply from a gateway. It start its probes with a ttl of one and increases this by one until it gets an ICMP “port unreachable” (or TCP reset), which means we got to the “host”, or hit a max (which defaults to 30 hops).

Options :
  • 4 ,6 : Explicitly force IPv4 or IPv6 tracerouting.
  • F : Do not fragment probe packets.
  • T : Use TCP SYN for probes. 

3. netstat (network statistics) is a command line tool for monitoring network connections both incoming and outgoing as well as viewing routing tables, interface statistics etc

Options :
• a : Listing all ports (both TCP and UDP)
• l : Listing all active listening ports connections • s : Displays statistics by protocol

 4. Ping command is a Command Prompt command used to test the ability of the source computer to reach a specified destination computer. The ping command is usually used as a simple way to verify that a computer can communicate over the network with another computer or network device.
The ping command operates by sending Internet Control Message Protocol (ICMP) Echo Request messages to the destination computer and waiting for a response. How many of those responses are returned, and how long it takes for them to return, are the two major pieces of information that the ping command provides.
Options:
  • a : This ping command option will resolve, if possible, the hostname of an IP address target.
  • t : Using this option will ping the target until you force it to stop.
5. arp command allows you to display and modify the Address Resolution Protocol (ARP) cache. An ARP cache is a simple mapping of IP addresses to MAC addresses. Each time a computer’s TCP/IP stack uses ARP to determine the Media Access Control (MAC) address for an IP address, it records the mapping in the ARP cache so that future ARP lookups go faster.
Options:
  • a : Displays current ARP entries by interrogating the current protocol data.
  • d : Deletes the host specified by inet_addr.

 



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