Determining your MTU, and why you should care.
DaleWhen we talk about networking, sometimes we’ll talk about Maximum Transmission Unit (MTU) packet sizing. I briefly referred to MTUs in the SSL errors, and how to diagnose them post.…
The Microsoft Loopback Adapter, NT4 & Windows 7.
Reading a Microsoft blog post recently, I was reminded of a customer request from late 2002. The emailed request was something like this: Had to use the generic Win NT4…
SSL errors, and how to diagnose them.
Frankly, I don’t know, but here’s what I learnt. It started with a customer reporting a problem When we press the publish button on the website, we get a 403…
Non Routable IP addresses
Non routable IP addresses are IP addresses which are not usable on the internet, but can be used on your home/corporate network. 10.0.0.0 - 10.255.255.255 172.16.0.0 - 172.31.255.255 192.168.0.0 -…
$20,000 because the customer didn’t want to be hassled with VPN tokens
A senior project manager reminded me of the power of Freedom of Information requests to stop things. Yes, we can do that for the Minister, but the Minister should be…
They don’t make networks hubs anymore
IF you wanted to analyse some network traffic, to see where things were going wrong, you would use a network hub. A network hub is one of the devices you…
Learning from implementing a change.
I, of course, researched everything beforehand and had it all planned out so that the implementation of the new policy went without incident. Well, maybe there was a little trial…
If you don’t have control of your network – Wireless Security
... then it's unmanaged and open to exploit. As happened with a customer in mid-2004. The "batphone" rings and it's one of our desktop support guys. "We're detected a wireless…
nPing – Diagnosing Lotus Notes network problems
Update October 2011: nPing can no longer be downloaded, see this workaround. Lotus Notes client didn't work at the Frensham Pond Hotel, when I stayed there. Long story short Ports…
We also know there are known unknowns – Network troubleshooting
Such as WAN link utilisation. Users were complaining that network performance was slow across the 80M WAN link. How did they know? Citrix users mostly ... So I ask our…