[nzlug] Bridging network cards and speeds

[Nick 'Zaf' Clifford]

Warren Boyd wrote:
> I use X-Windows over the network, I want to move that onto the Gigabit
> network to avoid the lag that comes from slower network speeds.
>   
Lag == latency
Slower network speeds == bandwidth

If you are experiencing lag on a 100Mbit LAN, then something else is
wrong, either that, or you are trying to play Open Arena over the X11
protocol.

To answer your original question, I can't see any significant problems
from bridging a Gigabit with a 100mbit network, as the bridge will
store-and-forward traffic. This will of course mean that communication
via the bridge (eg between hosts on either side) will only be at 100mbit
(or your CPU, whatever's slowest).

As for why you'd want to bridge the two physical networks, I don't know.
Just plug a decent gigabit switch into the network, and put the gigabit
devices on that, and the 100mbit devices can stay on the slower switch,
which is connected to one port on the gigabit.

If you are having any issues with network speed or reliability, please
please please look very closely at your network switches. Cheap switches
are notorious for having strange problems that all disappear when they
are replaced. (eg dropped packets, high latency, low bandwidth, etc).

We keep a small stock of 3com switches purely so we can go in to a
clients site, and replace their cheap switch with one, just to prove to
the client that it is a switch issue.

Nick