cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
170
Views
10
Helpful
8
Replies
Highlighted

Compare speed of Broadcast between 2 networks

Imagine:

I have 2 networks  

The first network with 10 Pcs in a Cisco switch 48 ports by IP subnet mask 255.255.255.240 

The second network with 5 Pcs in a Cisco switch 48 ports by IP subnet mask 255.255.255.0 

Question

 when I use a broadcast packet witch one works faster?

 The first one that has more Pcs with smaller subnet?

Or

 The second one that has less Pcs with larger subnet?

 

Thanks a lot

8 REPLIES 8
omz Enthusiast
Enthusiast

Re: Compare speed of Broadcast between 2 networks

Hi 

I must say wierd/interesting question.

If the mac-address-table is empty, the switch will send broadcast on all connected ports simultaneously regardless of the mask. A switch has no clue of the subnet mask .240 or .0. 

Re: Compare speed of Broadcast between 2 networks

Hi and thank you very much. 

omz Enthusiast
Enthusiast

Re: Compare speed of Broadcast between 2 networks

You are very welcome :) 

please don't forget to mark helpful posts.

VIP Expert

Re: Compare speed of Broadcast between 2 networks

"If the mac-address-table is empty, the switch will send broadcast on all connected ports simultaneously regardless of the mask."

Why would the MAC table or subnet mask vis-a-vis a broadcast (assuming we're not considering an IP subnet broadcast, even then the switch should [?] L2 broadcast to all connected ports in the L2 domain [leaving hosts to filter out an IP subnet broadcast they are not part of])?

Re: Compare speed of Broadcast between 2 networks

Is it possible to describe more?!

VIP Expert

Re: Compare speed of Broadcast between 2 networks

"Is it possible to describe more?!"

Probably. What specifically do you what a further description of?

Re: Compare speed of Broadcast between 2 networks

Thanks a lot.

I have got from your next comment.

 

VIP Expert

Re: Compare speed of Broadcast between 2 networks

Likely depends on the hardware of the switch, as a switch must physically replicate the broadcast to multiple ports. If not actually done fully concurrently, less ports to replicate for might be done a bit faster.

BTW, you're asking about an IP broadcast to all hosts and/or just an IP subnet broadcast? (Since you mention IP addresses and "packet", I assume you're not asking about L2 broadcast frames.)

I don't believe a switch would care at all about the two different types of an IP broadcast. I believe it would replicate either to all active ports in the same L2 domain and each host would need to filter out an IP subnet broadcast that's not part of their network (much like hosts need to do for multicast and/or unicast they physically "see" which logically they don't want [assuming we're discussing Ethernet, keep in minds the original shared wire linage of Ethernet]).
CreatePlease to create content
Content for Community-Ad