Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

Same subnet, different subnet mask, direct communication?

Posted on 2006-10-23
5
Medium Priority
?
302 Views
Last Modified: 2011-09-20
Hi Guys,
    I'm wondering if two computers on the same subnet can still communicate directly with each other, ie not through a router, if one has its subnet mask configured incorrectly, for example if the subnet of computer A is correctly 255.255.224.0 and the subnet of computer B is 255.255.0.0.
Yeh, i know that normally computers on different subnets have to go through a router or the default gateway but what if the subnet was configured like above?

Cheers,
phram3z
0
Comment
Question by:phram3z
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
  • 2
5 Comments
 
LVL 71

Assisted Solution

by:Chris Dent
Chris Dent earned 256 total points
ID: 17787481

Only if they are within the same most restricted mask.

Any traffic outside the mask range will be sent to the Default Gateway (unless a static route has been specified), the route back just doesn't work.

Chris
0
 
LVL 43

Accepted Solution

by:
Steve Knight earned 768 total points
ID: 17787580
Agreed.  They would have to be within the 255.255.224.0 mask, e.g. if you were using
10.0.0.0 ranges then

Devices all within the range 10.0.0.1 to 10.0.31.254 can communicate
Likewise 10.0.32.1 to 10.0.63.254 etc.

In situations where mask or gateway has been set wrongly easiest remote fix is to jump onto a box within the same subnet and reconfigure it from there.

In your case as the mask has been set too big it will communicate fine within it's local LAN but another IP (such as 10.0.127.1 in the example above, e.g. a device on another subnet or over a WAN) won't be able to communicate with it because packets won't return to the default gateway as they will be seen as local.

If a WAN link goes to another address range outside the 255.255.0.0 mask, again not an issue.

Any particular problem here or just after a bit of background?

Steve
0
 

Author Comment

by:phram3z
ID: 17787642
thanks doods =P quite helpful
0
 
LVL 71

Expert Comment

by:Chris Dent
ID: 17787673
Pleasure :)

Chris
0
 
LVL 43

Expert Comment

by:Steve Knight
ID: 17787766
No problem. Steve
0

Featured Post

Looking for a new Web Host?

Lunarpages' assortment of hosting products and solutions ensure a perfect fit for anyone looking to get their vision or products to market. Our award winning customer support and 30-day money back guarantee show the pride we take in being the industry's premier MSP.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

When you try to share a printer , you may receive one of the following error messages. Error message when you use the Add Printer Wizard to share a printer: Windows could not share your printer. Operation could not be completed (Error 0x000006…
During and after that shift to cloud, one area that still poses a struggle for many organizations is what to do with their department file shares.
Internet Business Fax to Email Made Easy - With  eFax Corporate (http://www.enterprise.efax.com), you'll receive a dedicated online fax number, which is used the same way as a typical analog fax number. You'll receive secure faxes in your email, f…
Here's a very brief overview of the methods PRTG Network Monitor (https://www.paessler.com/prtg) offers for monitoring bandwidth, to help you decide which methods you´d like to investigate in more detail.  The methods are covered in more detail in o…

704 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question