I'm gonna pull an all nighter working on this stuff and hopefully I'll wake up just in time to watch football.
I'm starting to grasp the OSI Model. Already it's helped me greatly. It really paints a clear picture of how data is transported from one device to another and the processes involved. For instance: on the "Transport Layer" it facilitates end-to-end communication between multiple applications simultaneously.
How does it do this? By using ports. Each application uses a specified port So it functions as a multiplex system. In other words, you can have multiple data streams working at the same time.
EDIT: Luckily I took a 2-year course on computer technology back in the day. That really helps out a lot. I know bits, bytes, multiplexing, ect. ect. If not for that, I'd be lost.
This may be boring to some but I find it fascinating.
Just going thought the OSI model and learning about Encapsulation and Decapsulation.
What does it mean.
It means as data works it way thru the 7 OSI layers that headers are added to the data for routing and other purposes. Once all the headers are added the data is ready to be sent to another device. When it reaches the destination device the headers must be stripped away...or in other words - "decapsulation." Once it's decapsulated, you're left with nothing but the raw data for the application that you're using...a webpage for example.
if you want a nice general approach to it with some good troubleshooting ideas... go look up google it support professional certificate... constantly evolving it is... but the course is quite detailed and taught by google guys... if you want to pay for it goto coursera... but you can get it on youtube for free Full-Google IT Support Professional Certificate - YouTube
and they really take you through the osi and how to understand it...
but you don't need to understand osi to fix copier network issues...
(case in point I only learned about that stuff 4 years into fixing it issues and never found it relevant...)
thats way too deep...
nice to know...
but way too deep...
the most you need is wireshark to understand the handshakes so you can know when they are missing...
(by the way best tool to have but hard to find is an old network hub... this way you can listen in on what copier and pc are saying to each other via wireshark)
handshake... like ping... you ping an ip address and you get a response... the response is the reply... the act of pinging and getting a response is an example of a handshake... you say hi... guy says hi... you make a deal you shake on it... you will go through a lot of those in IT but its all under the hood... if you know whats going on... then you can tell what went wrong...
So, I'm going through the TestOut labs and it's going pretty good and then I get to the OSI layer. This is kind of hard to grasp and TestOut does a crappy job of explaining it in a meaningful way. I had to go to Youtube to get a deeper understanding. I'm not there yet but this seems very important. Maybe not so much for copiers but then again, it can't hurt to know this stuff.
Sad To Say I Don't Have a Life
I do this stuff on the weekends too
comptia a+ and N+ does open doors to govt work in copier field and outside of it... so don't discount it...
you need an a+ to work on the toll road equipment in florida... nice paying job simple and time consuming...
and thats just one of many places... the good thing is if you get work that require them... they give you six months to a year to get certified...
Sad To Say I Don't Have a Life
I do this stuff on the weekends too
Try using Professor Messer's videos online, they are all free. There are videos for each module. Go watch the one for the OSI model, he helps make it easy to understand.
Just what I thought. Just like 99.9% of IT people that I have known you are all hot air and no substance. I usually end up having to solve the problems for them. Years of experience is worth a lot more than any certification. And if there is anything that I need additional information on, I have direct access on a daily basis to one of the leading computer science professors in the USA.
Try installing Wireshark and experiment. It’s totally free, and can run on Windows, Mac, or Linux.
There are some really good training videos on YouTube for Wireshark.
It’s not enough to just be able to run a capture; you need to understand what it’s trying to tell you.
I’ve used it many times over the years, and sniffed out some really goofy issues.
Note: Do NOT just “up and run it” at a customer site without their knowledge, as some of them won’t allow it. I got myself in deep do-do that way once.
“I think you should treat good friends like a fine wine. That’s why I keep mine locked up in the basement.” - Tim Hawkins
After about 5 hours of really studying the OSI model, I'm gonna give my honest assessment:
I think the OSI model is the foundation to understanding networking. I do think it a very valuable tool when troubleshooting a network. Now, if a person has years of experience, he probably doesn't think about it because it's become 2nd nature to him....he's been there done that. But for anyone that's new to networking, I think you should learn it. What is does is it gives you a blueprint for isolating the problem.
All OSI is is a logical flow chart that separates each job of the networking process from beginning to end. Understanding this will allow you to figure out where the problem lies. Or it narrows it down.
Disclaimer: I reserve the right to change my mind once I try to apply it in the real world.
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