Which of the following is a valid MAC address?

Which of the following is a valid MAC address?

• 193.165.2.1
• 00:D0:59:09:07:51
• 2007:0db8:85a3:0000:0000:8a2e:0470:7457
• 00:D0:59 

EXPLANATION

 A media access control address of a device is a unique identifier assigned to a network interface controller for communications at the data link layer of a network segment. MAC addresses are used as a network address for most IEEE 802 network technologies, including Ethernet and Wi-Fi. In this context, MAC addresses are used in the medium access control protocol sublayer.

The MAC address is formed in accordance to the rules of the three numbering name spaces, which are managed by the Institute of Electrical and Electronic Engineers (IEEE). The format is six sets of two digits or characters, separated by hyphens. An example of a MAC address is 30-65-EC-6F-C4-58.
Some manufacturers, such as Dell, place a unique identifier in the MAC address, which is called the Organizationally Unique Identifier (OUI), and identifies the manufacturer. The OUIs of some well-known firms are:

• Dell: 00-14-22,
• Cisco: 00-40-96,
• Nortel: 00-04-DC.

 

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Which of the following protocols doesn't require a connection?

Which of the following protocols doesn't require a connection?

• UDP
• THC
• IP
• TCP 

EXPLANATION

Tetrahydrocannabinol (THC) is one of at least 113 cannabinoids identified in cannabis. THC is the principal psychoactive constituent of cannabis. With chemical name (−)-trans-Δ⁹-tetrahydrocannabinol, the term THC also refers to cannabinoid isomers.
Like most pharmacologically-active secondary metabolites of plants, THC is a lipid found in cannabis,^[9] assumed to be involved in the plant's self-defense, putatively against insect predation, ultraviolet light, and environmental stress.^[10][11][12]
THC, along with its double bond isomers and their stereoisomers^[13], is one of only three cannabinoids scheduled by the UN Convention on Psychotropic Substances (the other two are dimethylheptylpyran and parahexyl). It was listed under Schedule I in 1971, but reclassified to Schedule II in 1991 following a recommendation from the WHO. Based on subsequent studies, the WHO has recommended the reclassification to the less-stringent Schedule III.^[14] Cannabis as a plant is scheduled by the Single Convention on Narcotic Drugs (Schedule I and IV). It is specifically still listed under Schedule I by US federal law^[15] under the Controlled Substances Act for having "no accepted medical use" and "lack of accepted safety". However, dronabinol is a synthetic form of THC approved by the FDA as an appetite stimulant for people with AIDS and antiemetic for people receiving chemotherapy.^[16] The pharmaceutical formulation dronabinol is an oily resin provided in capsules available by prescription in the United States, Canada, Germany, and New Zealand.

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VMWare files ending with the .VMX extension hold what kind of data?

VMWare files ending with the .VMX extension hold what kind of data?

• VHD connection data for the VM
• Type 2 data for the host to start the VM properly
• Primary configuration file and settings for the VM
• Virtual Machine Extension data for the VM 

EXPLANATION

The .vmx file is the primary configuration file for VMWare, storing the settings you selected using either the New Virtual Machine Wizard or the virtual machine settings editor.
If you created the virtual machine using an earlier version of VMware Workstation on a Linux host, this file may have a .cfg extension.

.vmx

<vmname>.vmx

This is the primary configuration file, which stores settings chosen in the New Virtual Machine Wizard or virtual machine settings editor. If you created the virtual machine under an earlier version of VMware Workstation on a Linux host, this file may have a .cfg extension

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What can you use the "route" command for?

What can you use the "route" command for?

• To set a fixed number of hops a packet can make
• To print the expected response time
• To determine the transit delay of packets
• To display and modify the routing table 

EXPLANATION

In computing, route is a command used to view and manipulate the IP routing table in both Unix-like and Microsoft Windows operating systems. Manual manipulation of the routing table is characteristic of static routing.
E:\Users\techlanda>route

Manipulates network routing tables.

ROUTE [-f] [-p] [-4|-6] command [destination]
                  [MASK netmask]  [gateway] [METRIC metric]  [IF interface]

  -f           Clears the routing tables of all gateway entries.  If this is
               used in conjunction with one of the commands, the tables are
               cleared prior to running the command.

  -p           When used with the ADD command, makes a route persistent across
               boots of the system. By default, routes are not preserved
               when the system is restarted. Ignored for all other commands,
               which always affect the appropriate persistent routes. This
               option is not supported in Windows 95.

  -4           Force using IPv4.

  -6           Force using IPv6.

  command      One of these:
                 PRINT     Prints  a route
                 ADD       Adds    a route
                 DELETE    Deletes a route
                 CHANGE    Modifies an existing route
  destination  Specifies the host.
  MASK         Specifies that the next parameter is the 'netmask' value.
  netmask      Specifies a subnet mask value for this route entry.
               If not specified, it defaults to 255.255.255.255.
  gateway      Specifies gateway.
  interface    the interface number for the specified route.
  METRIC       specifies the metric, ie. cost for the destination.

All symbolic names used for destination are looked up in the network database
file NETWORKS. The symbolic names for gateway are looked up in the host name
database file HOSTS.

If the command is PRINT or DELETE. Destination or gateway can be a wildcard,
(wildcard is specified as a star '*'), or the gateway argument may be omitted.

If Dest contains a * or ?, it is treated as a shell pattern, and only
matching destination routes are printed. The '*' matches any string,
and '?' matches any one char. Examples: 157.*.1, 157.*, 127.*, *224*.

Pattern match is only allowed in PRINT command.
Diagnostic Notes:
    Invalid MASK generates an error, that is when (DEST & MASK) != DEST.
    Example> route ADD 157.0.0.0 MASK 155.0.0.0 157.55.80.1 IF 1
             The route addition failed: The specified mask parameter is invalid.
 (Destination & Mask) != Destination.

Examples:

    > route PRINT
    > route PRINT -4
    > route PRINT -6
    > route PRINT 157*          .... Only prints those matching 157*

    > route ADD 157.0.0.0 MASK 255.0.0.0  157.55.80.1 METRIC 3 IF 2
             destination^      ^mask      ^gateway     metric^    ^
                                                         Interface^
      If IF is not given, it tries to find the best interface for a given
      gateway.
    > route ADD 3ffe::/32 3ffe::1

    > route CHANGE 157.0.0.0 MASK 255.0.0.0 157.55.80.5 METRIC 2 IF 2

      CHANGE is used to modify gateway and/or metric only.

    > route DELETE 157.0.0.0
    > route DELETE 3ffe::/32 

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Which option do you use with "ipconfig" to purge the DNS cache?

Which option do you use with "ipconfig" to purge the DNS cache?

• /cleanup
• /purgedns
• /cachedump
• /flushdns 

 EXPLANATION

Flushing the DNS cache on Windows  is a very easy process. Due to system security permissions, you must ensure that you run the command prompt as an administrator user.

1. Ensure that you're on the Windows Start Screen.
2. Simply type cmd and the Windows search bar will appear on the right hand side with search results.
3. Right click on Command Prompt and click Run as administrator
4. Type in the command ipconfig /flushdns

Linux

If you are running the nscd Name Service Cache Daemon and wish to flush your DNS cache, then you will need to do the following.

1. Open up a command terminal (either as root or run step 2 with sudo).
2. Run the command /etc/init.d/nscd restart

 

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