[BBLISA] STP and Fast Link

[Edward Ned Harvey]

> From: bblisa-bounces at bblisa.org [mailto:bblisa-bounces at bblisa.org] On
> Behalf Of Daniel Feenberg
> 
> We have a dozen Netgear "Smart" switches, most of whom allow one to
> turn
> on STP or Fast Link, and allow one to set a variety of parameters, such
> 
> Would turning either one of these on prevent the establishment of
> loops?

Spanning Tree Protocol, STP, is for the prevention of loops.  It causes
approx 30 sec delay when connecting a cable to that port.  It's common
practice (but not universal) to enable this in areas where people are
connecting their laptops etc.  Some schmo (or their 4-yr old kid on "bring
your kid to work day") might accidentally connect a patch cable from jack A
to jack B in the conference room or wherever.  Poof goes the network.

Fast Link is the opposite.  It's meant for use when you already know what's
going to be at the other end of the wire attached to this port, and there's
no possible way for it to cause a loop.  It's probably a device that you
leave always on.... such as a printer, a server, or another switch that's
very far away, in an area where there are no other switches connected to
this switch.

Since it's a device that you probably always leave on...  There's not a lot
of point to using fast link.  The only people who care about the fast link
are precisely the people who should be prevented from using it.  That is,
people who regularly connect or disconnect devices to the wall.