Basic Network Utilities
IPCONFIG
utility
The utility is used to determine the current IP protocol settings. By default, only the IP address, subnet mask, and default gateway are displayed for each adapter associated with TCP/IP. To display complete information about the configuration, set the /all key.
Ipconfig /all
Help on IPCONFIG and a list of command keys can be found by running it with the /? key.
Ipconfig /?
Tasks:
Examine the IP protocol configuration on your computer. Explain the meaning of the main parameters.
Find the network name of your computer.
Find the MAC and IP addresses of your computer
Display the contents of your computer’s DNS cache. Study the information received.
Clear the DNS cache. Make sure the cache is cleared.
PING
utility
The PING (Packet Internetwork Groper) utility is most often used to detect a basic network connection on TCP/IP networks.
To check the activity of a remote host, the PING utility uses a series of ICMP echo messages that determine the period for returning datagrams from the specified host and thereby allow you to “listen” to the network path to it.
The operating parameters of the PING utility are specified on the command line. In addition to the address (or name) of the host being checked, which is a required parameter, the user can set, for example, the response waiting time, intervals for sending requests, the number of request packets, packet size and other parameters that may be supported by the program depending on its version and operating system :
-f
— Sets a flag that disables packet fragmentation.
-i number
— Set the packet lifetime (TTL, time to live)
-n number
— Number of requests sent
-t
— Send packets before interrupt command
-l number
— Size of packet sent
-w number
— Response waiting interval in milliseconds
Tasks:
Find out the addresses of neighboring computers and determine their availability
Do the same, but setting the package size to 2kb and the number of packages to 10
Try to run the utility by setting the packet size to 30kb and disabling fragmentation. Explain your result. Determine the maximum packet size for your network experimentally.
Run the utility to send packets before the interrupt command. Stop sending packets using the Ctrl+C key combination.
TRACERT
utility
The utility allows you to determine the route of a packet from the user to the remote host.
The utility sends a sequence of UDP packets (3 packets by default), each with the TTL parameter set to 1, to a non-existent port on the remote host. The first router on the path destroys the packets and sends a “time exceeded message” ICMP message to the sender. which contain timestamps and the router address.
After this, the TRACERT utility sends packets with the TTL parameter = 2. These packets will reach the second router and will be destroyed by it. This way the sender knows the address of the second router.
The process will continue until the destination host is reached or the maximum number of hops is exceeded.
Tasks:
Learn the TRACERT command options.
Try to determine the route to any of the “neighboring” computers. (to speed up the utility, use the -d switch).
Try to determine routes to hosts with addresses 192.168.11.119, 192.168.1.55. Comment on the result.
ROUTE
utility
The utility is used to view and change the IP routing table on a given computer.
ROUTE
command syntax:
ROUTE [-f] [-p] command [address] [MASK mask] [gateway] [METRIC metric] [IF interface]
Commands:
PRINT
— Displays the route table on the screen
ADD
— Adding a route
DELETE
— Deleting a route
CHANGE
— Route change
Tasks:
Determine the list of IP protocol routes on your computer.
Add a new route to the list, specifying 192.168.11.119 as the gateway. Check the availability of the host to which you added the path.
Remove the previously added route.
ARP
utility
This utility is used to view and change the table of mappings between physical addresses and IP addresses used by the ARP protocol.
Utility parameters:
-a [address]
Displays a table of addresses. If the optional “address” parameter is specified, then only the record corresponding to this address is displayed.
-s ip_address mac_address
Adds a record to the table.
-d ip_address
Removes a record from the table.
Tasks:
Display the ARP table.
Determine the physical address of a neighboring computer using the ARP and PING commands. (if the address of the neighboring computer is not in the ARP table, you need to poll it using the PING command, after which the address should appear). Remember this address.
Clear the ARP table (you can use the wildcard * to denote all addresses)
Write a command to add an entry to the ARP table of a previously learned address. Check site availability. For which the entry was added.
NET
utility
The NET utility is used to manage the operation of most network services and operating system resources. The utility has a huge number of operating modes, depending on the specific implementation.
Common options for using the utility:
NET HELP [command]
Displaying a list of valid commands or help information for a specific command
NET CONFIG [SERVER | WORKSTATION]
Displays information about configuring workstation or server services.
NET VIEW /DOMAIN
Displays a list of local network domains
NET VIEW [/DOMAIN:domain_name]
Displays a list of computers in the current or specified domain.
NET VIEW \\computername
Lists the resources available for sharing on the specified computer.
NET USE
Displays a list of connected network resources
NET USE device_name\\computer_name\resource_name
Connects a computer to a shared resource
NET USE device_name /DELETE
Disconnects the computer from the shared resource.
NET START
Displays a list of services installed on this computer
NET START service_name
Starts the specified service
NET STOP service_name
Stops the specified service
NET PAUSE service_name
Suspends the specified service
NET CONTINUE service_name
Resumes execution of the specified service
Tasks:
List available NET utility commands
View help for some commands. Use the /? Or the HELP command.
Browse the list of domains on the network. View a list of computers in a domain. View a list of open network resources on a computer.
Map some network resource as a network drive. Use Windows Explorer to check the contents of the disk. Disconnect the network drive.