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PXE – Preboot Execution Environment

PXE – Preboot Execution Environment

Usually pronounced “Pixie”

For those who have visited or work in a corporate office, have you ever noticed how many workstations there are??? A LOT! Now you might also wonder how the respective IT department is able to deploy Operating Systems to these workstations. Almost every company/organization doesn’t want their IT department spending too much time on this, so installing and configuring every machine individually is out of the question.

Smaller organizations might store a preconfigured “image” of an OS on a portable storage medium (e.g. USB flash drive, portable hard drive), with all prerequisite drivers and programs already slip-streamed or injected into the image. But this method still requires you to be present to copy the image to the workstation. Most larger organizations won’t be doing it this way either.

So that brings us to network-based Operating System installation and configuration. In order to do this, we need to use a boot protocol called PXE (usually pronounced “Pixie”). Pretty much any modern BIOS/UEFI boot firmware will include an option to boot the workstation over the network using PXE. This will use the wired network card to get IP from DHCP to gain network access. Afterwards, a Proxy DHCP address is obtained which is the address of the boot server. A small bootloader will be retrieved from this server via TFTP, which will then perform the remainder of the boot process.

In terms of imaging, PXE will boot the workstation into an imaging console from your respective computer imaging software. This will allow you to pull an image from an imaging server an apply it to the local workstation. In fact, you don’t even have to be physically present at the workstation for any part of the process. If Wake-on-LAN is enable in the BIOS/UEFI, you can power on the machine over the network, have it boot via PXE, and run an unattended installation.

CD vs DVD??? Is there really a difference?

They look the same…

Most people would look at a CD or DVD and think that there is no difference. Well… THERE IS! Even though the two have the same appearance, they are not the same in terms of specifications.

Download this poster from https://wp.me/p8DWFt-b2

Even though the two have a similar physical appearance, they have different storage sizes and can even function differently.

For example, not all CDs are used for general purpose data. Some CDs can be burned as Audio CDs, which have a limit on audio duration rather than data size. The same concept applies to DVDs in terms of Video DVDs.

Older computers and players will not be able to recognize a DVD. This is because they were built to read only CDs. So the drive will either pop the disc out or return with an error. Always check the front of the drive tray to see what types of optical media can be read with it.

This logo is printed on drives capable of reading Compact Discs (CD)
This logo is printed on drives capable of reading Digital Versatile Discs (DVD)

Windows 7 End-Of-Life is approaching!

I guess people really take these software end-of-life announcements serious!

Yeah, it’s that time again! Everyone running Windows 7 on their computers will be out of support on January 14, 2020. No more security patches or bug fixes. This is going to be an exact replay of when Microsoft ended support for Windows XP back in 2014.

This pop-up brings back so many memories.

However, I am predicting that it will be WORSE in terms of the amount of computers that will continue running Windows 7 after the deadline. The two main reasons are that many IT Departments will not upgrade in a timely manner, and also because everyone flat-out hates the different design and functionality in Windows 10. At least it’s better than using Windows 8 🙂

This is one of the things that I like to see on a countdown timer, so I created one specifically for this “EVENT”.

Windows 7 EOL Countdown

Carry-on Baggage

A little off-topic for my blog, but something I wanted to write a post about after watching a Saturday Night Live (SNL) episode. This episode was a funny parody to boarding an airplane in real life. See it below:

Very funny episode! One thing that did catch my attention was the part with joke about carry-on baggage:

Of course that is just comedy. But in reality, many people will try to bring as large of a bag on-board an airplane to avoid having to check it to their destination. There are many reasons for this, such as not having to pay bag check fees, avoid potential damages to bags, and whatever other reasons there might be.

Many people are annoyed about this (including myself), as it causes airplane boarding and deplaning processes to take a long time. Also, people sitting below an overhead carry-on compartment can get knocked in the head when others are taking their heavy and over-sized “carry-ons” out of the compartment, causing injury.

The real question I have to ask is what is considered a carry-on? As the name implies, carry-on bags and items should be small enough to be carried by a person without having to touch the floor while moving. You aren’t “carrying” something, if it is being dragged or wheeled on the floor. Also, items that are carried onto an aircraft must be able to fit into an overhead baggage compartment or under the seat in front of you, with little to no struggle. If you have to squeeze and stuff your items into a compartment, they are not carry-on items by definition.

Despite the annoyance displayed by others, certain people still try to take advantage of the carry-on space with their over-sized bags, and force those with actual carry-on items to have no space for anything, further delaying departure of a flight. In addition to the inconvenience caused, someone can be severely injured by over-sized bags falling from the overhead compartments.

At the end of the day, if you are going to fly on an airplane, you need to be considerate of the other people you will be flying with. You also need to realize that flying on an airplane will require you to pay additional fees and check bags to your destination. It’s the cost of flying on airplane. Even though most checked bags make it all the way unharmed, don’t leave important items in your checked luggage, and don’t use expensive suitcases for air travel.

MyAbandonware.com

If you love playing vintage video games, then MyAbandonware.com has you covered. They’ve got thousands of vintage games available that have essentially disappeared over the years. Many of these games have been developed by individuals or companies that are no longer around or have decided to stop maintaining them. You can also contribute by sending them any old games that can be no longer found.

https://www.myabandonware.com/

CompTIA A+ Practice Tests

You can find CompTIA A+ Exam Information & Practice Tests at this website: https://www.examcompass.com/comptia/a-plus-certification/free-a-plus-practice-tests.

ExamCompass has a simple practice test interface, and breaks up tests into categories as defined in the certification objective.

Should User Account Control (UAC) be kept or removed from Windows?

User Account Control made its debut in November of 2006 with Windows Vista. It is designed to warn Administrators that a program they opened is about to make changes to their system. Also, it requires standard users to provide an Administrator’s credentials to allow programs to make changes to their system. Similar alerts exist within Mac OS X, as well as several Linux distributions.

What UAC prompts look like for Administrative users
What UAC prompts look like for Non-Adminstrative users
And a funny meme for those who dislike UAC

There are mixed opinions on whether this should remain an included feature with Windows. Now people on both sides of this “debate” have different computer setups that validate their reasoning.

Within business and corporate computer networks, many IT Departments already utilize Group Policy to set what Non-Administrative users can do with company systems. In addition, they can specify which programs can be run on a particular workstation. Lastly, any Administrative actions will still need an Administrators credentials and approval to complete an action. Rather than leave UAC enabled, some policies override and disable it, and also many IT Departments just manually disable it anyways. This will require Administrators to login to computer as an Administrator to complete the action. In fact, this was how Windows XP and prior editions were designed. UAC in these circumstances, essentially becomes a confirmation dialog, and not much more of a security feature.

Despite the above negativity from IT professionals towards UAC, it isn’t all that bad, and can be disabled if you desire.

Before I explain some of the benefits of UAC, you have to understand that it is geared towards consumers and small business users, who don’t possess the IT expertise to configure Group Policy and other advanced security measures. In fact, those who aren’t tech savvy are recommended to keep this feature enabled to its highest security setting. Also, since I mentioned earlier that Windows XP lacked UAC, home and small business users were common targets to malicious programs that modified system settings. This is because Windows XP gave all running programs the highest permissions that were available to the logged in user. Most users on home computers didn’t bother to create a separate user account without Administrative rights, and did their day-to-day work using an Administrator-enabled account.

In the end, UAC will probably remain within Windows, but you will have the choice to disable it (e.g. if you’re one of the people who hate it). But inexperienced home users will need to rely on it for security while using their computers. The choice is yours.

TCP vs. UDP

Should we use TCP or UDP? This is one of the questions that professional application developers might have to ponder. Most commonly, when they begin development on a future computer application that will rely on communication over the internet to operate properly. Both of these data transport protocols have their advantages, but they do come with disadvantages that turn certain developers away.

Before I begin explaining both protocols in technical detail, let me provide some insight to those who might not be familiar to this subject.

Data sent over computer networks is transferred through packets, which are of a specified size (typically 1500 bytes), which is known as the network’s Maximum Transmittable Unit (MTU). These packets are delivered to the next network and/or destination in an order defined by the respective transport layer protocol (e.g. TCP or UDP). These protocols are designed with a different goal in mind. Every networked computer application uses one or more protocols that will deliver data pursuant to the applications needs.

Transmission Control Protocol (TCP)

The Transmission Control Protocol (TCP) is designed to deliver packets and data across local networks and the internet, while doing so reliably. TCP would establish linked connections across the data path all the way to the destination, to ensure data arrives at the intended destination reliably. If the connection is interrupted the host computers at both ends would be alerted and would work to re-establish the connection. Even in the case of missing packets, TCP would keep track. Any communications sent over TCP are “handshaked”. This is both the origin and destination host computer confirming every transmission made.

This is the typical TCP connection and transmission demonstrated as a human conversation.
Get it?? TCP won’t stop trying to transmit packets… UNTIL YOU GET IT!

So, TCP already sounds like the best protocol! Why bother using anything else? Well, you won’t feel that way after reading about the one disadvantage of TCP.

While consisting of a reliable method for data packet transmission, this causes TCP to transmit packets at a slower speed than other protocols that weren’t designed with reliability in mind, such as UDP. Let’s head over and see what UDP has in store…

User Datagram Protocol (UDP)

User Datagram Protocol (UDP) is designed to allow rapid packet transmission over local network as well as the internet. Because of this, UDP does not establish reliable connection to the destination, and does not verify if a packet was ever received by the end host or if it was received in the right order. Think about someone telling you a phone number as you are dialing it, but they are not confirming that you dialed the number as you have said. It is a simple protocol designed with speed in mind.

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