Skip to main content
Image result for packet tracer





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.

 



Labels:

Comments

Post a Comment

Popular posts from this blog

Packet Tracer Simulation – TCP and UDP Communications Part 1: Generate Network Traffic in Simulation Mode Step 1: Generate traffic to populate Address Resolution Protocol (ARP) tables.  Click MultiServer and click the Desktop tab > Command Prompt.  Enter the ping 192.168.1.255 command. This will take a few seconds as every device on the network responds to MultiServer.  Close the MultiServer window. Step 2: Generate web (HTTP) traffic.  Switch to Simulation mode.  Click HTTP Client and click the Desktop tab > Web Browser.  In the URL field, enter 192.168.1.254 and click Go. Envelopes (PDUs) will appear in the simulation window.  Minimize, but do not close, the HTTP Client configuration window. Step 3: Generate FTP traffic.  Click FTP Client and click the Desktop tab > Command Prompt.  Enter the ftp 192.168.1.254 command. PDUs will appear in the simulation window.  Minim...
Post a Comment
Read more
Networking – SocketProgramming in TCP. Python provides two levels of access to network services. At a low level, you can access the basic socket support in the underlying operating system, which allows you to implement clients and servers for both connection-oriented and connectionless protocols. Python also has libraries that provide higher-level access to specific application-level network protocols, such as FTP, HTTP, and so on. What is Sockets? Sockets are the endpoints of a bidirectional communications channel. Sockets may communicate within a process, between processes on the same machine, or between processes on different continents. Sockets may be implemented over a number of different channel types: Unix domain sockets, TCP, UDP, and so on. The socket library provides specific classes for handling the common transports as well as a generic interface for handling the rest. Sockets have their own vocabulary − ...
Post a Comment
Read more
IMPLEMENTATION OF DHCP IN CISCO PACKET TRACER The Dynamic Host Configuration Protocol (DHCP) is a  network management protocol  used on  UDP/IP  networks whereby a DHCP server dynamically assigns an  IP address  and other network configuration parameters to each device on a network so they can communicate with other IP networks. A DHCP server enables computers to request IP addresses and networking parameters automatically from the  Internet service provider  (ISP), reducing the need for a  network administrator  or a user to manually assign IP addresses to all network devices.In the absence of a DHCP server, a computer or other device on the network needs to be manually assigned an IP address, or to assign itself an  APIPA  address, which will not enable it to communicate outside its local subnet. DHCP can be implemented on networks ranging in size from  home networks  ...
Post a Comment
Read more