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How to figure out your default subnet mask

A subnet mask is a 32-bit binary number, very similar to an IP address. And like an IP address, the subnet mask is usually expressed as a set of four octets written in decimal form, with each octet separated by a period.

The subnet mask is used by routers and switches to determine which part of a computer or other device's IP address is the network identifier, and which part is the host identifier. There are three default subnet masks, one for each of the IP classes A, B, or C. The default subnet masks are:

Class A = 255.0.0.0
Class B = 255.255.0.0
Class C = 255.255.255.0

To determine the default subnet mask for your network, all you need to do is see which class your network falls into. A network's class is assigned based on the first octet (the set of digits before the first period) of the IP address. For example, to find out which class the network 123.22.8.0 belongs to, you would see where "123" fits into the following table:

First Octet: Class:
1-126 = Class A
128-191 = Class B
192-223 = Class C

So for the example above, 123.22.8.0 is a Class A network, which means it would have a default subnet mask of 255.0.0.0.

Most home and office networks will be Class C networks, so your default subnet mask will typically be (you guessed it) 255.255.255.0. Not all networks use the default subnets, but for those that do, figuring it out is easy once you know which class your network fits into.

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hi. i cant connect to print server d-link dp301p+ IP to configure it?! who knows what IP by default it have? 192.168.0.10 doesnt work... Thanks, Mike


First find out the IP address , Subnet mask,and Gateway addresses of your ISP ( Internet Service Provider ). According to above addresses, you have to complete the network settings of your printer by mentioning the different IP address .

To find out the above mentioned addresses, first open the control panel -> network connections -> local area connction -> properties -> Internet Protocol Version 4(TCP/IPV4) OR Internet Protocol Version 6 (TCP/IPV6)according to your ISP -> Properties

By the systematic selection as mentioned above you will get the IP address, subnet mask and Gateway addresses.

Suppose your IP address is 192.168.0.10 , the gateway may be 192.168.0.1 Or any number. And the subnet mask may be XYY.XYY.XYY.0.

According to your ISP addresses you have to complete the network settings of your printer. First press the additional functions -> system settings -> network settings -> TCP/IP settings -> fill up the addresses as follows.

IP address : 192.168.0.16 OR any number .

subnet mask : XYY.XYY.XYY.0.

Gateway : 192.168.0.1

Hurray ! the problem about your network connection with the printer to your computer will be automatically solved.

Sep 28, 2010 | Computers & Internet

1 Answer

low lan connectivity or limited lan connectivity


Hello Sir,

all computers on the same physical subnet need to have ip addresses in common
meaning the first three numbers in aaa.bbb.ccc.ddd are the same and are different only in the ddd portion.
In addition, the subnet mask must be alike or ensure that some ip addresses are not excluded
Typical subnet mask is 255.255.255.0 or sometime 255.255.254.0
Usually, there's a gatway address; a target which is used to send packets out
of this machine and hopefully towards the other machine.

For all machines, use the Run->cmd and enteripconfig /allYou should have similar results on all machines, so look for major differences eg: gateway on one is 0.0.0.0 or not shown while other have non-zeros,
or ip address on one start 169.254 another starts with 192.168

The 169.254.y.z addresses are pecuilar

ms article comments on auto-config:
example : IP-address assigned via Auto-IP-Configuration :
Windows IP Configuration
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
Autoconfiguration IP Address.. . . : 169.254.4.69
Subnet Mask . . . . . . . . . . . . . .: 255.255.0.0
Default Gateway . . . . . . . . . . . . :



Thanks
Cheers!!!!!!
Good luck

Feb 29, 2008 | Computers & Internet

1 Answer

putting right the ip address ?


Before you proceed you need to know the static IP, Subnet Mask and Gateway address for this printer. Once you have them: -Enter the menu mode by pressing the + button -Press the + button till you come to the Network Menu. -Press the Enter button. You should now see TCP/IP. Make sure it says Enabled which is the default setting. -Press the + button till you come to IP address then press the Enter button. - IP addresses (for now) consist of four octets or four groupings of three numbers such as in this example *192.168.001.123*. Using the + or - buttons (+ counts up 0,1,2,3?.; - counts down 255,254,253?..) you are going to set the number of the first octet or in the case of the example *192*. Once you?ve set it correctly hit the Enter button. -Do the same for the other three octets. Hitting the Enter button after setting the fourth octet will set the new IP and take you back to the TCP/IP menu. - Press the + button till you see Subnet Mask and press the enter button. - Just like the IP address the Subnet Mast consists of four octets. Set the value to you needs just as you did with the IP address. Again when you hit the enter button after setting the fourth octet you will be taken back to the TCP/IP menu. - Again press the + button till you come to Gateway Address and hit enter. Enter the Gateway IP address exactly like you did when setting the IP address. Don?t forget to hit the enter button to set the address. You should now be at the TCP/IP menu again. -To exit the menu press the On-line button on the printer. Your printer should now be configured with you IP address, subnet mask and gateway address. As an added check I would go back into the menu by pressing the + button, going into the Information Menu and printing selecting the Print Menu Map option. Verify the setting we just made with what is printed out at the top of the page. If everything matches you?re ready to go! Let us know how it goes and please don?t forget to rate this posting.

Jan 22, 2007 | OKI C5100n Laser Printer

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