Tag: wireless

Networking: People and Computers

Learning Objectives

    • Define the term networking. Explain that networking goes beyond just technology.
    • Explain the importance of communication.
    • List ways that technology can help make communication between humans more effective. Mention real world examples of communication platforms.
    • Explain that computer networking can enable positive and negative communication.

What is Networking?

You may have heard the term “networking” before. The word “networking” can mean different things. You could define networking as, “the linking of computers to allow them to operate interactively”. At least, that’s how Oxford defines it. In this section and for all other sections in the series, let’s define networking using IBM’s definition, which is “defining a set of protocols (that is, rules and standards) that allow application programs to talk with each other without regard to (their) hardware and operating systems”. There’s networking in technology, but there’s also networking in everyday life. When we network with different people, we learn about them. We learn things such as their likes/dislikes, where they come from, and even who they’re related to. If we compare technology to human beings, you might be surprised to hear that technology and human beings communicate in similar ways.

Now, that doesn’t mean you’re a robot…

Though, I admit, being a robot for a day would be kinda cool…

The point is humans create technology, so it makes sense that we would create things in a way we understand. In later sections, we’ll see examples of how computers talk to each other. For now, let’s just keep the idea that technology and human beings communicate in similar ways.

Ok, so we now know that technology and humans communicate similarly, so what?

If we take a step back and look at how we live our lives, do you think communication is important?

I would say, “Heck yeah!”

Without communication, how would we know how a person feels? If you were sick and needed help, how would you be able to signal someone? Simple human communication, like talking, can only go so far. Facial expressions and non-verbal cues are other ways that we can communicate. Going back to talking, what happens if you want to talk with someone who is not physically with you?

Maybe we could reach them by megaphone?

That might get annoying for the other people around you, and on top of that, the person you intend the message for may not be around to hear it. It’s possible that the person you want to talk to may be 2,000 miles away!

Going back to the megaphone, what happens if you want the message to be heard only by that specific person? Maybe the message is a secret. Screaming your secret through a megaphone would definitely make that no longer a secret.

Computers to the Rescue!

Computer networking can solve many of these communication problems. First, some computer networks have the ability to send data at the speed of light, which given a medium like single-mode fiber, is roughly 124,188 miles per second. That’s quicker than any speech I could give!

Computers also have the ability to use encryption, which can make things for peeping eyes very hard to read.

Let’s say we had the following file of text:

the cat is in the tree.

Let’s now look at that same file when it’s encrypted using a 256-bit AES cipher:

U2FsdGVkX1/ysfGqqcUyY9dzVVKt3AgKs9SphLA9VwN1M01ry9rwJ5/hss+fBKQA

I don’t know about you, but I don’t understand a word of that!

Networking is important, whether humans do it directly or use a computer to assist. Computers have allowed us to communicate in ways that redefine what it means to be human. Think about it, we have social media like Facebook that can connect you with people from all over the world. We have cellular networks that make talking with someone over the phone happen in seconds! We even have applications like Google Meet where several people can meet using video.

Just like human communication, communication using computer networks can have positive and negative consequences. With data traveling at crazy speeds, information can be spread quickly to all corners of the world. While relaying life saving news can be seen as a positive, bullying a classmate over social media can be seen as a negative.

As we learn more about computers and how they talk to each other, please remember that we must act morally. A computer can do quite a bit of harm if someone tells it to. When using technology, let’s network positively and solve problems that can make this world a better place to live in 🙂

Resources & Review

Credits

Images provided by Creative Commons contributors.

Defending Yourself From Cyber Attacks

People have asked me what they can do to protect themselves from being hacked. First, let me clarify something very important: NO ONE WILL EVER BE 100% SAFE FROM A HACK. With the constant changes in technology, there will always be new vulnerabilities that hackers will try to exploit. This is unfortunately the world we live in. That being said, the inevitability of an attack shouldn’t deter you from adopting good security practices. Here are some basic steps in protecting yourself from hackers:

1.) There’s always antivirus

Years ago, I would’ve recommended antivirus on all devices. Unfortunately, background processes associated with antivirus applications consume an excessive amount of computing power. Personally, I don’t use antivirus. Being a Debian guy, I run ufw. If I notice anything suspicious, I’ll investigate network/socket traffic and system processes. If you want to use antivirus, there are several providers to choose from. Remember, smartphones are computers too. Smartphones are just as vulnerable as a computer when it comes to malware.

2.) Always use HTTPS when you can

HTTPS stands for “Hypertext Transport Protocol with Security” or “Secure Hypertext Transfer Protocol”.  The HTTPS protocol uses an encryption framework known as SSL or “Secure Sockets Layer”. This provides a bidirectional encryption tunnel between the data you are sending and receiving. Using SSL makes it very difficult for a hacker to eavesdrop on a connection. Think of HTTPS as creating a “protection tunnel” between you and a website. Your data is being transmitted through this tunnel of encryption so that no third-parties can know what you’re doing.

You can check to see if a site has HTTPS by requesting it (i.e. https://www.bing.com or https://www.google.com). If you type your site in with HTTPS and a lock comes up, then you should be going over an encrypted connection. Now, a big misconception about HTTPS is that if a site has HTTPS, it’s legit. THE PRECEDING IS NOT TRUE! Just because a site provides HTTPS, doesn’t mean it’s legit. Always do a background check before submitting data to a site, no matter what type of encryption and protection it offers.

3.) Secure your wireless network

Securing your wireless network is another way of protecting yourself from hackers. Hackers can perform an action called “wardriving”. Wardriving is when a hacker scans around for insecure networks. If they find a network that is insecure, they will connect to it and sniff the traffic. Network traffic may contain sensitive information about yourself (e.g. credit card numbers). Always implement strong passphrases and use modern security frameworks (e.g. WPA2 or WPA2-EAP).

4.) Incorporating a network firewall

Adding a network firewall & web filter increases your security greatly. However, this requires more technical knowledge. Network firewalls can run on a dedicated computer and intercept all data that goes out to the Internet. This can provide the capability of scanning websites for malware and blocking users from getting to them. There are many different types of open source firewalls available (e.g. pfSense).

5.) VPNs

Just as incorporating a network firewall can be difficult, VPNs can be equally challenging. However, many home routers now provide a built-in VPN implementation (e.g. OpenVPN). When people are on the go and need to access resources from home securely, VPNs are a perfect solution. VPNs or Virtual Private Networks enable users to access data from a different network without physically being there. For example, someone can connect to a VPN provided by their employer and access work-related documents from home. You can also implement a VPN at home for Internet privacy. Let’s say you’re browsing the web at a local cafe. The cafe’s WiFi is public, so a malicious user could sniff around and intercept your traffic. However, if you connect to your home VPN and route your Internet traffic through the VPN, the only traffic that may be visible is an encrypted request to your VPN. Everything else will go out your home’s Internet connection.

(Originally posted on February 8th, 2015. Updated on December 29th, 2020)

How Safe Is Your Wireless Network?

People will come up to me and ask, “Is my Wi-Fi password strong enough?” or “Is my wireless network secured?”. This is often a difficult question to answer because no matter how secure a network is, there are always vulnerabilities. Wireless networks can be exploited several ways. Some common causes include: weak passwords, insufficient encryption, and believe it or not, huge data transfers. If a wireless network has a weak password, then access could be achieved within minutes. Passwords should never be predictable. Weak security mechanisms, such as using outdated encryption, can also leave your wireless network exposed. If you are going to secure your home wireless network, at least use WPA2 (Wi-Fi Protected Access v2). WPA2 uses AES encryption, and when compared to TKIP, can stand a chance against a more powerful attack (see this link to read a little more about AES vs. TKIP encryption). WEP is also highly susceptible to replay attacks and should be avoided at all costs.

Just the other day, I got familiar with aircrack-ng. aircrack-ng allows you to lock onto a specific BSSID and capture traffic that comes in contact with your network adapter. If your network adapter can support airodump-ng, then you can sniff packets from an AP and potentially crack a Wi-Fi password. In order to execute attacks like that, massive data transfers must be occurring when the hacker sniffs the wireless network. If there’s not a lot of data being transmitted, then the attack will take longer to execute. Packet injection via aireplay-ng can come in handy for generating noise. An attack that could take days to execute can happen within minutes if a hacker’s network card supports packet injection.

If you really want to be secure (to the point of inconvenient), here are some security mechanisms you can implement:

  • Using a strong encryption mechanism
  • Enable hidden SSID
  • Configure a MAC address filter
  • Implement an IDS endpoint
  • Use WPA2 Enterprise (802.11x) in order to add authentication/accounting via an intermediary (e.g. Microsoft NPS/RADIUS)

(Originally posted on April 27th, 2014. Updated on September 13th, 2020)