Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 13 May 1998 14:24:58 -0700
From:      Doug Wellington <ddw@NSMA.Arizona.EDU>
To:        freebsd-net@FreeBSD.ORG
Cc:        ddw@cortex.NSMA.Arizona.EDU
Subject:   Number of hubs on a net...
Message-ID:  <199805132124.OAA27971@cortex.NSMA.Arizona.EDU>
In-Reply-To: Your message of "Wed, 13 May 1998 23:31:03 %2B0300." <Pine.LNX.3.96.980513232648.22417D-100000@avrasya.ispro.net.tr> 

next in thread | previous in thread | raw e-mail | index | archive | help
Previously:
>at my office I want to expand my network with installing
>new hubs, how many hubs I can connect together? 

Hubs are just multiport repeaters, and we follow the "four
repeater rule" - that is, no more than four repeaters between
any two devices.  Of course, once you get to a bridge, switch
(which is just a multiport bridge) or router, you can start
counting all over again...


>and what can happen if I install too many hubs like this?
>would it cause collusion on my network? 

No, it won't cause a collision, and that is the very problem.
Computers at the ends of the network won't realize that the
last packet they sent really did result in a collision, and
they won't know to resend it.


>(well another thing I should ask it, why does collusion 
>occurs on a network?)

Ethernet is designed that way.  It's like being at a party.
Anyone can talk at any time, and sometimes more than one person
will start to talk at the same time.  Then each person, or each
network device, will wait a small period of time and then start
to listen again to see if anyone else is talking.  If nobody else
is talking, then that one can try again.

The other way to set up a network is with each computer passing
a "token" around.  Only the computer with the token can talk.
If that computer doesn't need to talk, it just passes the token
on.  (Token ring or token bus...)

Doug Wellington
ddw@nsma.arizona.edu
Network and System Administrator
ARL, Division of Neural Systems, Memory and Aging
The University of Arizona, Tucson, AZ
(520) 626-6023
(520) 291-0481 pager
(520) 626-2618 fax

I DON'T buy anything from spammers, and I KEEP TRACK OF WHO SPAMS ME.

I put up with ads on the TV because they pay for programming.  When
spammers pay for the Internet, then I'll start putting up with spam.

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199805132124.OAA27971>