Difference between TCP and UDP

If you work with computers, you probably have heard about the TCP and UDP protocols. While they both are mechanisms to transmit data to other computers, they do not operate in the same manner. Below I’ll show you some differences between the two data protocols.

TCP (stands for “Transmission Control Protocol”)

  • It’s a connection-orientated data protocol
  • TCP is best used for applications that require high reliability
  • There is more overhead (more computer resources used) when using TCP
  • Other protocols such as: HTTP, HTTPs, FTP, and SMTP make use of the TCP protocol
  • TCP makes sure that the order in which data is received is the same order in which it was originally sent
  • TCP is typically slower than UDP
  • TCP allows for “flow control”
  • TCP checks for errors in the data transmission
  • TCP acknowledges segments
  • TCP has both error checking and options to recover in-case of an error

UDP (stands for “User Data-gram Protocol”)

  • Not a connection-oriented protocol
  • UDP is useful for applications that need fast transmission of data (regardless of data integrity)
  • Less overhead when using UDP, since UDP is a connectionless protocol
  • Other protocols such as: DNS, DHCP, and VOIP make use of the UDP protocol
  • UDP does not make sure that data received is in the same order that it was originally transmitted (less reliable, but faster)
  • UDP is typically faster than TCP
  • UDP has no “flow control”
  • UDP does not check for errors in the data transmission (less reliable, but faster)
  • UDP does not acknowledge segments
  • UDP has error checking but does not have any way to recover from errors it detects

Posted in Computers, Internet and Servers, Operating Systems

Akamai Discovers Linux Botnet that Hits with 150 Gbps DDoS Attacks

According to a web article, Akamai (a Content Delivery Network company) discovered a massive Linux botnet. A botnet is basically a bunch of compromised computers that allow attackers to perform various tasks that would otherwise be virtually impossible to accomplish without everyone’s compromised computers.

Basically, the botnet comes in the form of a Trojan. This Trojan targets Linux systems (including network routers). Once it gets into the system, it proceeds to download software to connect the computer to the botnet. The botnet is reportedly able to give up to a 150 Gbps DDoS** attack.

As I have said on my blog repeatedly, Linux is not immune to security problems. No operating system on the planet is immune to security problems. In this case, it is people using weak, insecure passwords on their Linux boxes.

If I set my Windows box’s Administrator password to ‘password123’ or ‘qwerty’, enabled remote desktop on my computer, and allow remote desktop through the firewall, I would eventually get hacked. Was that Windows’ fault or Microsoft’s fault? No, of course not. It would be my fault for setting a bad password on my computer.

Many people say “Linux is more secure than Windows”, but if you notice – most of the time – they do not give any technical arguments to backup what they said.

For example, a part of one of someone’s comment posted online said (direct quote):
“The primary attack vector to take over these systems is default or weak login passwords, and allowing internet-facing remote root. That has no bearing on Linux suddenly being less secure than it was yesterday, or in any way magically now just as insecure as Windows.”

Notice he said “That has no bearing on Linux suddenly being less secure than it was yesterday, or in any way magically now just as insecure as Windows.”, but he did not give any technical arguments to backup what he said.

What is worse is people will listen to them, assuming they are correct (e.g., Linux is more secure than Windows), and go off and repeat the same misinformation around on the Internet without even bothering to check if the information they received is in fact accurate.

Web article link: https://www.engadget.com/2015/09/29/linux-botnet-hits-with-150-gbps-ddos/

** Simply put, a DDoS attack is basically an attack that uses up the victim’s available bandwidth. This causes the victim’s computers to not correctly function when communicating with the outside world and internal network.


Posted in Computers, Internet and Servers, Operating Systems, Software

Even More Windows FUD

I received this comment that someone posted online. In case anyone is wondering, I try to keep the authors’ names and/or usernames of different comments, articles, blog posts, etc. I respond to anonymous.

The comment was riddled with misinformation and untruths about Windows. I will place the comment author’s comments below in red. My responses are in black. Please note that I mean no disrespect to the comment’s author in anything I say.

It is funny because if you walk into any major company, even Microsoft, you will find a majority of the servers running Linux.

While there are a lot of companies that make use of Linux (and probably have several Linux servers), I highly doubt that Microsoft uses many (if any) Linux servers themselves. Do you have a source to verify this?

It is also funny that they think Windows is more secure.

What makes you think Linux is any more secure than Windows? You did not provide any technical arguments.

Windows has not fixed any major security holes in years because it is impossible to do so. The software runs in the operating system instead of a sort of run time container.

  1. To say that Windows “has not fixed any major security holes in years” would mean that Microsoft does not give security patches to Windows. This is, of course, a false statement.
  2. Why would it be “impossible” to fix major security issues in Windows? You gave no technical arguments to backup your statement.

Open Source ensures that any security holes found can be fixed within minutes of finding them. Windows has to officially release patches for every fix and those fixes can only be made by Microsoft.

Not true! The Bash ShellShock vulnerability took days to get all the official patches out.

“Initial solutions for Shellshock do not completely resolve the vulnerability. It is advised to install existing patches and pay attention for updated patches to address CVE-2014-6271, CVE-2014-7169, CVE-2014-7186, CVE-2014-7187, CVE-2014-6277, and CVE-2014-6278. Red Hat has provided a support article with updated information.”   —   Source:  https://www.us-cert.gov/ncas/alerts/TA14-268A

In other words, the current patches are not a 100% guarantee that the ShellShock vulnerability has been completely patched.

I don’t think you understand fundamentally how the Windows operating system works from the perspective of a low level developer. If you look at the Windows source you will see that it has almost not been touched since XP.

Not true!  Windows 7 alone had the following features added to the OS such as:

Final point is that Ubuntu, which in the Linux community is considered Windows with a custom theme, has that title for a reason. Besides being pure Linux on the backend, the front end is basically the same as Windows.

Ubuntu Linux is not a complete replacement for Windows. There are many programs (such as:  Adobe Photoshop, Microsoft Word, Visual Studio)  that either have no Linux equivalent, or the “equivalent” software program is not up to par.

It is also one of the biggest Linux communities in the world. If you have a problem, you can find a solution normally within a few minutes by asking online in any Linux community weather it is programming or general usage. I should know because I use Linux as my main OS.

You can usually find quick answers to Windows questions online.

You have the question as well, infrequent tested patching or ultra frequent fixes that can quickly be refined by a large userbase that puts it through actual non-simulated testing. The answer is obvious.

Community testing of patching (a.k.a fixes) is a good way to know if what you fixed is actually fixed! However, this does not mean that professional testers are “worse” than community testers. In other words, don’t assume community software testers are “better” than professional software testers.

————————————-

Of course I use both Windows and Linux myself and am not a Windows fanboy, but it is a pet peeve of mine to hear incorrect Linux statements made from people as well as Windows FUD spread by people who do not know what they are talking about.


Posted in Computers, Operating Systems

More Windows FUD (Fear, uncertainty and doubt)

Today I received a notification containing a comment someone posted to one of the OS talk websites I have visited before.

This person commented with an obvious bias against Windows and really did not make good arguments for Linux. By the way, this is in no way a “Windows is better than Linux” blog post (I use both Windows and Linux myself), nor do I mean any disrespect to the comment’s author.

Here is the comment (word for word) posted in red:

“on hardware support, you may think Windows is better, but it’s not. Windows is worse, MUCH worse. it does have ok hardware support, and there are a lot of devices that support it, but it’s not the manufacturers writing the drivers, it’s the community, and it’s built in to the kernel. Linux does support more hardware and supports them better. a good example is the graphics driver. on Windows, the default graphics driver is pretty bad, 3D Acceleration is not supported, OpenGL doesent work and, Colors on some chipsets are terrible (Like 4 or 8 Colors), and the resolution is low. the worst you will get with most linux distro’s is a low resolution, but most distro’s work pretty good out of the box.”

I am going to respond to this a little bit at a time. My responses will of course be in black.

————

“on hardware support, you may think Windows is better, but it’s not. Windows is worse, MUCH worse.”

How is Windows “much worse” in regard to hardware support? Almost all consumer-grade hardware (from the last 20+ years) have / still work with Windows. You need to give a source for what you claimed. I suspect this argument is FUD.

“it does have ok hardware support, and there are a lot of devices that support it, but it’s not the manufacturers writing the drivers, it’s the community, and it’s built in to the kernel.”

Pretty much to get the optimum performance out of your hardware, you need to use the manufacturer’s drivers for your hardware (that goes for Windows, Linux, UNIX, etc.)   Community reverse-engineered drivers probably will not cut it.

“Linux does support more hardware and supports them better.”

While Linux does support more hardware on paper, realistically most of the hardware everyday people and businesses use will work with Windows. Windows is not limited to x86 hardware. Both Windows Phone and Windows Embedded Compact work with ARM processors. Also, Windows Embedded Compact works with MIPS and SuperH architectures as well.

Saying that Linux “supports them better” is a blanket statement that should not be made without credible proof. I suspect this argument is FUD.

“a good example is the graphics driver. on Windows, the default graphics driver is pretty bad, 3D Acceleration is not supported, OpenGL doesent work and, Colors on some chipsets are terrible (Like 4 or 8 Colors), and the resolution is low.”

While 3D acceleration is not supported out of the box on Windows (referring to Microsoft’s Basic Windows Display Driver), you should be going ahead and installing the video card’s manufacture’s drivers anyway.

Yes, I know about nouveau on Linux (nouveau is an attempt to build an open-source Nvidia compatible video driver, by reverse engineering Nvidia’s proprietary Linux drivers), but this does not work as well as Nvidia’s proprietary video drivers.

Also, I am not sure what you mean by “Colors on some chipsets are terrible (Like 4 or 8 Colors)”. Most modern hardware (even back 10 years ago) would not be that bad out-of-the-box on Windows. I suspect this argument is FUD.

“the worst you will get with most linux distro’s is a low resolution, but most distro’s work pretty good out of the box.”

Same goes for Windows.


Posted in Computers, Operating Systems

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