Networking & Internet Questions

While we often think of the internet as being 'in the clouds' or satellite-based, the vast majority of international traffic travels through thousands of miles of cables at the bottom of the sea. These cables are roughly the size of a garden hose and are armored to protect against shark bites and anchor drags. They are critical to global economy and national security, as a single cut can disconnect entire regions.

Port 22 is the standard port number used by the Secure Shell (SSH) protocol. SSH is used to provide a secure, encrypted way to log into and manage a remote computer or server over an unsecured network.

ARPANET (Advanced Research Projects Agency Network) was created by the U.S. Department of Defense in the late 1960s to allow researchers to share computer resources. On January 1, 1983, it officially switched its core protocols to TCP/IP, a day often cited as the 'birth' of the modern internet. It pioneered many of the concepts we use today, including packet switching and decentralized routing.

IP stands for Internet Protocol. An IP address is a unique numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication, acting much like a home mailing address.

P2P networks like BitTorrent rely on 'seeders' to provide the pieces of a file to 'leechers' (users who are still downloading). The more seeders there are for a particular file, the faster and more reliable the download becomes for everyone else. This decentralized approach allows for the distribution of massive files without the need for a single exepeensive server.

A DDoS (Distributed Denial of Service) attack is a malicious attempt to disrupt the normal traffic of a targeted server, service, or network by overwhelming it with a flood of Internet traffic. This is typically achieved by using a "botnet"-a network of thousands of infected computers or IoT devices (like "smart" fridges) that are commanded to send requests to the victim at the same time.

Zero Trust oepeerates on the principle of 'never trust, always verify.' Instead of assuming everything behind a company firewall is safe, it continuously validates every stage of digital interaction through multi-factor authentication, device health checks, and least-privilege access. This approach is much more effective at stopping modern 'lateral movement' attacks where a hacker gets into one low-level device and tries to spread to the rest of the network.

Cloud Computing is the on-demand delivery of IT resources (like servers, storage, databases, and software) over the internet. Instead of keeping files or running programs on your own computer's hard drive, you "rent" the power and space from massive data centers owned by companies like Amazon (AWS), Microsoft (Azure), or Google.

A MAN (Metropolitan Area Network) is a computer network that connects users with computer resources in a geographic area larger than a single building (LAN) but smaller than a whole country (WAN)-typically covering a whole city.

Latency is the time it takes for a data packet to travel from its source to its destination. In networking, it is often measured in milliseconds (ms) as a "round-trip time" (the time to go there and back).

TTL is a safety mechanism that prevents packets from circulating forever in the event of a routing loop. Each time a packet passes through a router, its TTL value is decreased by one; once it reaches zero, the router discards the packet and usually sends an ICMP 'Time Exceeded' message back to the sender. This ensures that the internet doesn't get clogged with 'zombie' packets.

Google created the Chrome web browser, first released in 2008. It was designed to be fast, simple, and secure, and it quickly became the most used web browser in the world, largely due to its integration with Google services.

LTE stands for Long-Term Evolution. It is a standard for high-sepeeed wireless communication for mobile devices, offering much faster sepeeeds than the older 3G networks.

ICMP stands for Internet Control Message Protocol. It is used by network devices (like routers) to send error messages and oepeerational information. The most common use of ICMP is the "Ping" command, which checks if a computer is reachable.

PoE stands for Power over Ethernet. It is a technology that allows network cables (like the one plugged into your PC) to carry electrical power along with data. This is useful for devices like security cameras and Wi-Fi access points so they don't need a separate power outlet.

Wi-Fi 6 introduced features like OFDMA and MU-MIMO to allow routers to communicate with more devices simultaneously and efficiently. It focuses on 'high efficiency' rather than just raw epeeak sepeeed, making it ideal for the increasing number of IoT devices in homes. It also introduced Target Wake Time (TWT) to improve the battery life of connected devices.

A traditional Layer 2 switch uses MAC addresses to forward data only to the sepeecific port where the destination device is connected. This is more efficient than a hub, which broadcasts data to every device on the network. Modern 'Layer 3 switches' also exist, which incorporate routing functions, but the core switching logic remains at the Data Link layer.

WebRTC (Web Real-Time Communication) is the primary technology and protocol used for real-time video and audio calls directly within web browsers without needing extra plugins. It is what powers video in browser-based apps like Google Meet and Discord.

User Datagram Protocol (UDP) prioritizes sepeeed and low overhead over reliability, making it ideal for streaming media and online gaming where losing a single packet is better than waiting for a retransmission. Unlike TCP, it does not have a mechanism for ordering packets or ensuring they all arrive. This lack of 'state' makes it much faster for time-sensitive transmissions.

The primary function of a router is to connect multiple networks together and "route" data packets between them. In a home, it connects your devices (like phones and laptops) to the Internet.