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Broadcast Domain Design

Anyone know the recommended size (number of hosts) or limit for a broadcast domain?

Documentation much preferred.

Thanks in advance,



Re: Broadcast Domain Design

I don't know of any official documentation, but typically 250 hosts is the maximum for Windows ( you can go higher with Linux). This is also keeps subnetting at a minimum and helps in overall IP design as well.

Hope that helps.

New Member

Re: Broadcast Domain Design

The smaller the better! /24 is probably the maximum number of IP's you would want on a given subnet.


Re: Broadcast Domain Design

Nobody has a link?

Re: Broadcast Domain Design


This is a very good question.

The number of hosts in a subnet depends on many considerations you have to do in planning and designing a network.

Among these considerations there is a security issue: if you want, for example, segment hosts in VLAN and then create different broadcast domains. But the main consideration is:" What applications and operation systems you have?". If you have the possibility, use a network analyzer in order to determine the broadcast traffic. If this is high possibly reduce the subnet hosts.

I hope this helps.

Best regards.


New Member

Re: Broadcast Domain Design

Appreciate your response.


Best Regards,

Farhan Siraj Patel

New Member

Re: Broadcast Domain Design

I like this query and it is easily understood why a network engineer would question this.


Smaller broadcast domains are recommended.


The reason being that more devices you have in a broadcast domain, then:


1. ARP request received by any device in broadcast domain is to be processed.

Resource utilization viz. CPU, memory of all devices in the broadcast domain thus increases.



2. Broadcast is sent to all devices in broadcast domain which also adversely affects bandwidth utilization.


Hope this helps.


So we need to ensure that broadcast domain is not too big so as to have too many devices.

Proper segmentation using segmentation techniques viz. VLAN, DMZ is recommended.


Best Regards,

Farhan Siraj Patel

Re: Broadcast Domain Design


Dont think there is any recommendation - but larger broadcast domain means more chance of network performance issues and higher risk of security hacks.



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