[LUNI] [OT] Ethernet wiring for industrial/factory environment

[Arun Khan]

A client location has a mixed office and factory environment.  They have 
around 35 hosts Windows/Linux 60/40 mix.

The LAN is flat with 4 10/100 switches (DLink 16 port) cascaded through 
the entire office/factory building.  One DLink switch serves the office 
section while the other 3 are in various locations of the factory 
floor.

Stations located on the factory section complain about slow response 
from the server running the ERP system (running on a Debian server 
located in the office section) every so often, whereas the guys in the 
office say the response time is OK.

I took a site inspection and noticed that the guys who had installed 
their wiring had not crimped the RJ45 connectors properly and the wires 
are Cat5 UTP.  The wiring goes past heavy machinery at several spots on 
the floor.

I suggested the first thing they should do is get the ends of the wire 
crimped properly.

However, my main concern is "industrial" EMI that may be causing 
degradation in network performance.  Results from ntop and wireshark 
show normal traffic on the LAN i.e. no virus/trojan flooding the 
LAN/WAN links.  

Using shielded cable and industrial grade ethernet switches is an option 
(@ add'l cost).

I would appreciate if anyone can share his/her own experience for such 
an environment before I suggest to the client to budget for an upgrade 
to his LAN infrastructure.

-- Arun Khan