Tuesday, 17 November 2009

Duplex mismatch

So bloody annoying and I have tried an SOR in to our favourite telco and they just ignore us.

Why oh why do they insist on setting Ethernet ports to fixed full duplex. not even auto negotiate announcing only full duplex - but fixed full duplex.

Every bloody time we are involved in any way with an install people get this wrong. People are used to networking just working, but if you connect to any of this telco's circuits that is Ethernet (under 1Gb) you must have a managed switch port of some sort that you can manually set to the right speed and full duplex.

There are many bits of kit that will not allow you to set that or don't work. The best bet is a managed switch, and they tend to be a few hundred quid.

It is just so damn stupid of the telco.

FYI gigabit is only sane because the standard prohibits them fucking this up.

1 comment:

  1. I work for an ISP which sells layer 2 ethernet circuits (NOT the telco you're talking about). We always fix the speed on the ethernet ports because certain manufacturer's equipment will happily work on auto-negotiate ports... for a while. Then suddenly it'll drop to half-duplex all on it's own with no prompting, and the other side will remain at full-duplex. Spontaneous duplex mismatches make customer angry.

    TL;DR - Bad switch/router maker makes telcos and ISPs hardware their ethernet port settings.