To find counterfeit they teach you what good money looks like. When you are looking at a sniffer trace you are generally looking for something that is not right. Ralph Brandt Communications Engineer HP Enterprise Services Telephone +1 717.506.0802 FAX +1 717.506.4358 Email Ralph.Brandt@pateam.com 5095 Ritter Rd Mechanicsburg PA 17055 -----Original Message----- From: Scott Helms [mailto:khelms@ispalliance.net] Sent: Friday, February 17, 2012 11:24 AM To: nanog@nanog.org Subject: Re: Common operational misconceptions On 2/17/2012 10:18 AM, Steve Clark wrote:
I agree with this 100%.
Having worked with many people over the last 40 years, the good trouble shooters understood how things were suppose to work. This helps immeasurably in determining where to start looking.
This is dead on and why I always start classes with a refresher on the OSI model. While the model isn't perfect it lets technicians and engineers construct a reasonable model of how things *ought* to be working. While you certainly will run into devices that bend or even break the rules (sometimes for good reasons) its much easier to understand the exceptions if you know the normal operation for a repeater, bridge, or router. -- Scott Helms Vice President of Technology ISP Alliance, Inc. DBA ZCorum (678) 507-5000 -------------------------------- http://twitter.com/kscotthelms --------------------------------