Author Topic: multiple gig-e switch question  (Read 190 times)

Offline eagl

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multiple gig-e switch question
« on: July 23, 2009, 10:24:20 PM »
Hello,

I ended up with a little capacity problem on my home lan, combined with a distance problem.

First, I found that my wife's work demanded a wired connection instead of wireless, but her office is on the far side of a largish 2-story house, and it's somewhat problematic for me to run a wire from where our cable modem, router, and existing gig-e switch sits to her office.  At a minimum, it will require installing 2 wall plates, but one of them is not accessable from the attic unless I drop it in through the ceiling (ugly).  So for a temp fix, I ran a wire from my switch down the hallway, and since the cable wasn't quite long enough I plugged in a second gig-e switch and plugged my wife's computer into that switch.  Because I was irritated about bad wireless connectivity on that whole side of the house, I also plugged a second wireless router into that switch and configured it as an access point.  So far, so good, it seems to work fine with decent connection speeds (faster than 10/100 by far, with transfer peaks near 25% network capacity and sustained between 17 and 20%, about what I expect with the hard drives in use).

Any other ideas, other than those ethernet adapters that use home power lines?  Or just suck it up and hire someone to drop the cables through the wall to a properly mounted wall socket?

Now the other problem.  With the cable going to my wife's office, I am now one port short on my 8 port gig-e switch in my own office.  Don't ask how I can use up 8 ports...  but I did.  The question - I have a really spiffy looking US Robotics 8 port switch handy.  It looks like the type they sell to small businesses... internal power adapter so no wall wart, metal case, more diagnostic lights, etc.  Will I see any real performance decrease if I just chain this to my existing gig-e switch?

The network would then look like this

Cable to cable modem
Cable modem to router
Router to one gig-e switch (handles dhcp and all firewall functions)
Two more gig-e switches hanging off of the first gig-e switch
All computers and my NAS are hanging off of one of the gig-e switches, so they can all talk at gig-e speeds without being slowed down by the 10/100 ports on the router and the 10mbps port on the cable modem.

Before you say it, YES I KNOW that internet traffic still goes through the 10mbps port on the cable modem.  Duh.  I'm talking about internal lan traffic here.

So, any problems you can see adding the additional switch?  Thanks in advance!
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Offline Ghastly

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Re: multiple gig-e switch question
« Reply #1 on: July 24, 2009, 07:40:54 AM »
I would not recommend the powerline networking solutions.  They are relatively poor in comparison to a wired solution, and the ones I had tended to cause a significant amount of interference with other radio devices.  They also ran very very warm, and tended to die relatively quickly.

( And I won't even mention that when one of them went bad, it took out the Internet for the entire TOWN I live in, because it was constantly broadcasting on the same frequency as that used by the cable company and until they disconnected our house from cable, no one in town could get Internet connectivity).

And no, "chaining" the switches won't decrease performance by a measurable factor, until you "chain" through so many that the end to end propagation delay is such that you begin inducing collisions and timeouts.  How many is too many is tough to say, because it depends upon how much delay each device introduces, and whether it's a store and forward switch, etc - but 3 to 4 is never going to be too many to the best of my knowledge even with consumer grade equipment, especially if you are using switches versus hubs (if they even make 1 gb hubs, which I doubt.)   

<S>


« Last Edit: July 24, 2009, 07:42:36 AM by Ghastly »
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Offline eagl

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Re: multiple gig-e switch question
« Reply #2 on: July 24, 2009, 08:05:00 AM »
Thanks.  That's sort of what I thought, but I wanted to run it past some other people to make sure I wasn't missing something. 
Everyone I know, goes away, in the end.