The YubiKey is a hardware device that generates passcodes for 2-factor authentication (2FA). It is not a password manager and does not store username/password pairs for your online accounts. It is a pure 2FA device that generates HMAC-based One Time Passwords (HOTP) and Time-based One Time Passwords (TOTP) that you can plug (or NFC) into your smart device. The YubiKey is recognized as a human interface device (HID) and delivers password as if the keystrokes are coming from a keyboard.

Microsoft lagging behind Google and Apple on browser war, and also fell behind on the password manager debut. Microsoft finally completed its password manager beta testing, and officially released Autofill password manager that utilizes Microsoft Authenticator. This is good news for Edge users, but Chrome users on the Mac, Windows, iOS, and Android can also benefit from it. We all know creating strong passwords for online accounts is a hassle, and remembering them is even worse. More free tools like Autofill will help online users from steering away from using weak passwords and reusing the same password for multiple accounts.

Google password manager is built into the Chrome web browser, and it interacts with the web forms automatically if you're using the Chrome browser. The first time you submit a login form, the Chrome browser will prompt if you want to store the username and password pair in a vault on your computer, and whether you want to sync them to the cloud on your Google account. The next time you visit the same site, once you enter the username portion of the form Google Chrome will auto-populate the password field. If you sync your passwords with your Google account, all the passwords are available on every device you use as long as you use Google Chrome and sign onto your Google account.

A local area network (LAN) is a group of smart devices connected together to create a network within the same location. A home is a good example of LAN consisting of a few computers, tablets, smartphones and IoTs devices over the physical wires and through the Wi-Fi. A LAN can be as small as connecting 2 devices or as large as enerprise network interconnecting thousands of computers, servers and smart devices. A few other examples of LAN include offices, buildings, schools, and corporations.

Both TCP and UDP are protocols used to send data from one device to anoter within the TCP/IP network. When sending data, they are broken into smaller IP packets and sent over the TCP or UDP transport layer. Applications may choose to use either TCP or UDP to send data to the other end depending on whether the reliability or speed is more important. For reliable delivery, TCP is used while UDP is used for faster delivery. TCP/IP is comprised of 4 layers with each providing a specific protocol functions as shown below:

An Autonomous System (AS) is a large network that has a common routing policy used to serve a set of IP prefixes. An AS is assigned to a single organization and is connected to multiple ASes to route IP packets in a redundant manner. An AS is assigned a 16-bit or 32-bit number (ASN) by the IANA to Internet Service Providers (ISPs), governments, universities, and enterprises.

A RIR (or Regional Internet Registry) is a nonprofit organization that allocates Internet Numbers which is comprised of IPv4 Addresses, IPv6 Addresses, and ASN (Autonomous System Numbers) within their respective regions. An IP address is a globally unique number that is assigned to computing devices to communicate with each other within a network (or Internet). ASN is a group of one or more IP prefixes that are used to define routing policy. With IP Address and ASN, IP packets are routed from one IP address to another regardless of where they are located within the world. There are 5 RIRs in the world, and their serving regions:

Apple's iCloud keychain is a password manager for macOS and iOS devices including Macs, iPhones, and iPads. Username/password pairs, credit card information, Wi-Fi credentials, and other personal data can be stored in iCloud, and shared amongst all of your Apple devices. Your personal data are encrypted with 256-bit AES, and saved in your iCloud, and transferred to and from iCloud to your devices encrypted so it is very secure. The data stored in your keychain can be accessed through Safari, and some third-party Apple apps but not with Google Chrome, unfortunately.

2FA (2-factor authentication) is a form of MFA where a user is required to supply 2 forms of authentication to allow access to the system. The traditional authentication system used the username/password pair to grant access to an account, but a growing number of hacking due to the use of weak passwords prompts the industry to offer an additional form of authentication to enhance the security of login access.

Web browsers today offer a built-in password manager, and auto-populate username and password on the websites you visit. This is a very convenient feature offered by virtually all web browser makers including Google Chrome, Safari, Firefox, and Microsoft Edge. The question is whether you can trust browser password managers to store your passwords without a security risk.