Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am setting up the network for our small companies new office - I have about 20 computers upstairs and 20 down. There is a switch on each floor, the router is downstairs, and a cat5e cable running between floors. All computers should be on the same subnet.

Is there any difference in connecting both switches to the router(Route A) or connecting the switches directly to each other(Route B) and only one switch to the router? I know both approaches will work, just wondering if there is a reason to prefer one or the other. Thanks Network Layout

share|improve this question
up vote 12 down vote accepted

When you connect two switches together, you are extending your broadcast domain. The broadcast domain can impose a burden in fairly large networks. When you connect each switch independently to the router, there will be a broadcast domain for each switch, thus controlling the broadcast traffic passing through your network.

share|improve this answer
While that is normally true, in this case it appears that the side of the router he is plugging in to is actually a switch, and not independent port (correct me if I'm wrong). In this case, there is almost no different in which route he uses, except if the router is only 100mbps and the switches are gigabit. – KJ-SRS Dec 1 '11 at 18:25
I think most home/small business routers, like the ones with 4 ports, simply uses an unmanaged switch controller chip to provide the 4 ports as KJ-SRS describes. One simple indicator is whether the original firmware mandates which port must be WAN. You can also log into the router and run ifconfig to see how many ports can be controlled independently. – Dec 1 '11 at 18:45, They often will not show up in ifconfig until you configure them to be. Thats not a surefire test. – user606723 Dec 1 '11 at 19:10
As stated above, the answer is incorrect. In both cases you will only have one broadcast domain, unless the router has the ability to do VLAN partitioning and you configure it to partition. – Collin Anderson Jul 14 '12 at 16:49

Amongst other things (like what haroldmoma mentioned), another to consider is that if you chain the switches together and the first one dies, the second one will also stop working (everyone is offline). If you attach them both to the router, then one failing won't affect the other (only half the office is offline).

share|improve this answer

if you chain the switches the switch closest to the router will get more traffic than if you put them parallel (where it will all go through the router) depending on your usage (heavy internet accesses needed vs heavy access to own fileserver) you can weigh one off to the other

and it also provides a single point of failure besides the router (as mentioned by techie007)

share|improve this answer
Since almost all low-cost switches use store&forward (rather than cut-through) packet handling, the traffic load can be an issue. Also there is a performance handicap (albeit small) when daisy-chaining switches. A store&forward switch has to fully buffer every Ethernet frame before it can be retransmitted, and this will add to latency. – sawdust Dec 1 '11 at 20:29

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.