Core 1 Condensed

What is the max transfer speed for USB 1.0?

1.5 Mbps

What is the max transfer speed for USB 1.1?

12 Mbps

What is the max transfer speed for USB 2.0?

480Mbps

What is the max transfer speed for USB 3.1 or SuperSpeed USB?

5Gbps

What is the max transfer speed for USB 3.2?

10Gbps

What is the max transfer speed for USB 3.3?

20Gbps

What is the max transfer speed for USB 4.0?

40Gbps

Serial Advanced Technology Attachment (SATA)

Standard method of connecting a storage device to the motherboard inside of a desktop computer

SATA Revision 3

6000 Mbps or 6Gbps (you will often find that devices you connect to do not support speeds that fast, so the data transfer will be slower than 6Gbps. For example, if you are using a modern hard drive of 7200 RPMs, it simply can’t spin fast enough to transfer the data at 6Gbps.)

Serial Attached SCSI (SAS)

High performance data transfer technology used mainly in enterprise environments for connecting storage devices to servers and workstations.

1. Data transfer speeds of up to 24 Gbps

2. Full duplex communication and high scalability

3. Backward compatible with other SATA drives

4. Enterprise level reliability with features like dual port architectures

5. Designed for 24/7 operation

DDR3 SDRAM

Runs at a lower voltage and at a higher speed than DDR2 (240 keyed pin connector). DDR3 throughput is 6.4 to 17 GB/s with a maximum module size of 8 GB per memory module.

PC5-42000 (DDR5 module)

42 GB/s

Parity Memory

Performs basic error checking and ensures the memory contents are reliable. It is slower, but has that reliability needed for servers and certain high end desktop workstations.

Error Correcting Code (ECC)

A type of memory that takes parity up to the next level by detecting and correcting an error. In order to use this, the motherboard and the CPU has to support it.

Buffered/Registered Memory

Additional hardware (register) between memory and CPU. a hardware feature that manages electrical loading so the CPU doesn’t overload.

Redundant Array of Independent Disks (RAID)

A specialized storage config that combines multiple physical HDDs or SSDs. A redundant array of independent disks, allowing multiple physical hard disks to be combined into a single logical hard disk drive inside the operating system.

1. RAID 0 is great for speed but provides no data for redundancy — great for high speed gaming

2. RAID 1 is a mirrored disk array. Every single thing put on disk zero is also put on disk one. Gives full redundancy, but you get a loss of storage because half of your storage is used for redundancy, which means you pay a lot more for storage costs than if you use RAID 0.

3. RAID 5 — gives you redundancy through parity. You won’t have a full copy of everything. It uses a minimum of 3 disks. Basically if one part is lost it can calculate the missing part — 2 + __ == 5. This is one of the most common raids, heavily used in most server environments and by most small businesses.

4. RAID 6 — same as RAID 5 but now we have double parity, so now we have 4 disks instead of 3. In RAID 6, you can lose 2 disks and keep operating whereas with RAID 5 you could only lose 1.

5. RAID 10 — a RAID of RAIDs. Two RAID 1s placed inside a RAID 0 config.

6. Failure Resistant — like RAID 1 or RAID 5 protects against loss of array data if a single disk fails.

7. Fault Tolerant — like RAID 1 or RAID 5 or RAID 6 continue to function if a single component such as a drive or cards fails

8. Disaster Tolerant — A RAID system has two independent zones with full access to the data at all times - RAID 10

Cable Modem

Device that translates coaxial cable signals into radio frequency waves.

Cat 5 (Fast Ethernet)

1. Standard — 100BASE-TX

2. Bandwidth — 100 Mbps

3. Distance — 100 meters

Cat 5e (Gigabit Ethernet)

1. Standard — 1000BASE-T

2. Bandwidth — 1000 Mbps or 1 Gbps

3. Distance — 100 meters

Cat 6

1. Standard — 1000BASE-T | 10GBASE-T

2. Bandwidth — 1000 Mbps | 10 Gbps

3. Distance — 100 meters | 55 meters

Cat 6a and Cat 7

1. Standard — 10GBASE-T

2. Bandwidth — 10 Gbps

3. Distance — 100 meters

Cat 8

1. Standard — 40GBASE-T

2. Bandwidth — 40 Gbps

3. Distance — 30 meters

T568A and T568B standards

standards that help us define the wiring configuration for our ethernet cables. Each standard specifies the order of the 8 wires inside the twisted pair cable, when they’re crimped inside the RJ45 connector. The key difference between them lies in the arrangement of the green and orange interior wire pairs. T568A is mainly used in older installations and the government. T568B are used in commercial and residential installations.

F-type Connector

A threaded metallic connector that will screw on to a coaxial jack on the cable modem or the wall jack.

Orthogonal Frequency Division Multiplexing (OFDM)

Divides data transmission into smaller subchannels that can each carry a portion of the data. Most common method used in our modern Wi-Fi networks. This technique minimizes interference and enables higher rates of data.

2.4 GHz Frequency Band

Operates within the frequency range of 2.4 to 2.5 GHz and is characterized by its longer range due to its lower frequency. However, it is prone to interference from devices like microwaves, bluetooth, and cordless phones because they all use similar frequencies. To avoid overlap, channels 1, 6, and 11 are commonly used.

5 GHz Frequency Band

Covers a frequency range of 5.725 to 5.875 GHz, though specific ranges may vary by region. Provides up to 24 non-overlapping channels.

6 GHz Frequency Band

Spans frequencies from 5.925 to 7.125 GHz and introduces up to 59 non-overlapping 20 MHz channels.

Wireless Networking

Covered by a group of standards known as the 802.11 standards.

802.11

Operated in the 2.4 GHz spectrum at speeds of just 1 to 2 Mbps. Not commercially viable.

802.11a

Introduced in the late 1990s and it operated in the 5 GHz spectrum at speeds up to 54 Mbps.

802.11b

Much more affordable and operated in the 2.4 GHz spectrum at 11 Mbps..

802.11g

Operated in the 2.4 GHz spectrum but increased speeds to 54 Mbp.

802.11n (Wi-Fi 4)

This wireless N standard operated in both the 2.4 GHz and 5 GHz spectrums and allowed it to acheive speeds between 300 and 600 Mbps.

802.11ac (Wi-Fi 5)

Operating exclusively in the 5GHz spectrum, Wireless AC can achieve thoeretical speeds of up to 3.5 Gbps.

802.11ax (Wireless AX) (Wi-Fi 6/6e)

The latest evolution in wireless networks, supports 2.4 GHz, 5 GHz, and 6 GHz frequency bands. At 9.6 Gbps.

Internet Protocol Version 4 (IPv4)

introduced in the eray 1980s, the most widely used protocol for assigning unique addresses to devices on a network. Each device, whether its a computer, smartphone, or server, needs to have a unique address to be able to send and receive data. We can represent around 4.3 billion unique IP version 4 addresses. Has 4 octets in dotted decimal notation like 123.233.43.0

Network Address Translation (NAT)

allows multiple devices to share a single public IP address, extends the usabiility of IPV4. your router gives them private IP addresses (which only work inside your house) and uses one single public IP address to communicate with the rest of the world.

Class A Address

always begin with a number between 1 and 127 in the first octet and they use a default subnet mask of 255.0.0.0. The first octet represents the network portion and the remaining 24 bits are going to be reserved for identifying the host within that network. This means that a Class A network can support 16.7 million unique host addresses per network. These networks are ideal for really large organizations that needs extensive amounts of address space.

Class B Address

start with a number between 128 and 191 in the first octet, and use a default subnet mask of 255.255.0.0. The first two octets represent the network portion and the remaining two octets are going to be used for the host portion. These networks can support up to 65,536 host addresses per network. Going to be suitable for medium and large sized organizations.

Class C Address

begin with numbers between 192 and 223 in the first octet, and they use a default subnet mask of 255.255.255.0. First three octets represent the network portion, and the last octet is reserved solely for host addresses. Can support up to 256 unique addresses. Commonly used in small office and home office environments.

Class D Address

start with the value between 224 and and 239 in the first octet, and are reserved for multicasting. Does not have a default subnet mask because it is not intended for typical network or host addressing. Used to send data packets to multiple devices simultaneously, since they’re often used for streaming services or group communications.

Class E Address

start with a value between 240 and 255 in the first octet, and they are reserved for experimental purposes and are not used for regular internet traffic.

Classless Inter Domain Routing (CIDR)

replaced the fixed class system with a more flexible approach to subnetting and address allocation. Introduced in 1993, CIDR threw away the rigid classes. It allows us to draw the line between the "neighborhood" (the Network) and the "house" (the Host) anywhere we want. It lets us carve up networks into custom, precise sizes so no IP addresses go to waste. Instead of relying on standard 255.255.255.0 style masks, CIDR introduces Slash Notation (like /24 or /22). This slash tells you exactly how many bits of the 32-bit IP address belong to the network portion. A /22 means the first 22 bits belong to the network, and the remaining 10 bits belong to the host.

CIDR Notation

Specifies the subnet mask with a slash (“/”) and the number of network bits. For example, 192.168.1.0/24 because the first 24 bits are being allocated to the network portion. It enables subnetting to divide larger networks into smaller subnetworks and this is accomplished by borrowing bits from the host portion of the address and reallocating them to the network portion of the address. Because of CIDR, routers on the internet don't need to know where all 65,000 of your devices are. They only need one single routing rule: "If the data starts with 10.0., send it to Noah's company router." Once the data hits your company router, your internal router looks at the next set of bits to see if it goes to IT (10.0.1.x) or HR (10.0.2.x). When you subnet, you steal a few bits from the front of the host portion and reassign them as a sub-street identifier: [--- NETWORK PORTION ---] [-- SUBNET --] [--- HOST PORTION ---]

Internet Protocol Version 6 (IPv6)

developed to address IPv4 limitations, solve address exhaustion, and enhance efficiency, scalibility, and security. Has 340 undecillion possible addresses. Each address has 8 segments of 4 hexadecimal digits separated by colons — 2001:0db8:000:000:000:000:2a4e:0370. We are allowed to remove leading zeroes to shorten the notation — 2001:db8:0:0:0:0:2a4e:370. Also a sequence of zero segments can be replaced with a double colon to shorten the address as follows — 2001:db8::2a4e:370. The double colon can be used only once in a IPv6 address to avoid ambiguity.

File Transfer Protocol (FTP)

Operates on ports 20 and 21 and is used for transferring files between a client and a server.

Secure Shell (SSH)

Uses port 22 to provide secure, encrypted access to a remote computer. Commonly used for managing servers via command line interface because it ensures that data and login credentials are being protected from eavesdropping.

Telnet

Operates on port 23 and allows remote access to a computer using a text based interface, similar to how SSH does. It is considered to be insecure because it transmits data, including passwords in plaintext.

Simple Mail Transfer Protocol (SMTP)

uses port 25 to send email messages, has been in use since the 1980s and remains the standard for outgoing email messages.

Domain Name System (DNS)

Operates on port 53 and translates human readable domain names like www.google.com into IP addresses.

Dynamic Host Configuration Protocol (DHCP)

uses ports 67 and 68 to automatically assign IP addresses and other network settings.

Hypertext Transfer Protocol (HTTP)

Operates on port 80 and is the foundation of the Wrold Wide Web.

Post Office Protocol 3 (POP3)

Uses port 110 to retrieve email from a server

Network Basic Input/Output System and NetBIOS over TCP/IP (NetBIOS and NetBT)

uses ports 137 and 139 to facilitate file and printer sharing on Windows networks.

Internet Message Access Protocol (IMAP)

Operates on port 143 and provides advanced email retrieval to allow users to manage messages directly on the server.

Lightweight Directory Access Protocol (LDAP)

uses port 389 for directory services, such as managing user accounts and groups in environments like Microsoft Active Directory

Hypertext Transfer Protocol Secure (HTTPS)

uses port 443 and is the secure version of HTTP

Server Message Block and Common Internet File System (SMB and CIFS)

operates on port 445 used for file and printer sharing

Remote Desktop Protocol (RDP)

uses port 3389 and allows users to remotely control another computer through a graphical interface.

DORA

A process DHCP uses, its a 4 step process, and it stands for Discover (device discovered), Offer (DHCP server offers ip address), Request (device requests to use that ip address), and Acknowledge (DHCP acknowledges request and provides ip address and receipt). It set up the IP address, subnet mask, default gateway, and DNS server’s IP address. All 4 of these must be set up for a device to communicate outside of its LAN.

IP Address: "Here is who you are."

Subnet Mask: "Here is a map of who is in the room with you."

Default Gateway: "Here is the door if you need to leave the room."

DNS Server: "Here is the phonebook so you can look up where you want to go."

Virtual Local Area Network (VLAN)

critical concept in modern networking that allows for the logical separation of devices within the same physcial network. When a traditional switch without VLANs is used in a network, all the connected devices become part of a single broadcast domain. Leads to unnecessary network traffic and reduced network security. VLANs group switch ports into seperate broadcast domains as if on different physcial switches. Now you can keep the IT Department and HR Department separate without having to buy seperate switches and routers. VLANs enables a single switch to support multiple departments by assigning ports to specific VLANs. In summary, it creates a logical separation between networks on shared hardware, reducing the need for duplicate equipment. They help enhance secrutiy by isolating traffic and improving effieciency by limiting broadcast domains.

Subnetting is about who gets what IP addresses. VLANs are about which ports on a switch are isolated from each other. A classic real-world example: a coffee shop might have one physical switch but three VLANs — staff, POS terminals, and guest Wi-Fi — so a customer on the Wi-Fi literally cannot reach the payment system, even though it's the same building and same hardware.

Note:

Your access point doesn't physically downgrade its hardware capabilities to the lowest common denominator, but the performance results feel like it does. The network slows down because the AP is forced to spend valuable airtime catering to the slow transmission speeds and coordination requirements of older devices.

If you have a fast internet connection and want to maximize your network performance, the best practice is to move legacy or Smart Home (IoT) devices to a completely separate 2.4 GHz guest network, leaving your main 5 GHz or 6 GHz bands running in a modern, restriction-free mode.

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