The Early Layers
This bottom layer of the OSI model defines physical media specifications like Ethernet, wireless, or fiber, and handles bits.
What is Layer 1 (Physical Layer)?
This is the standard modular connector type used for Category 5 through 8 twisted pair cables.
What is RJ45?
This is the maximum distance that standard Single-Mode Fiber can travel before signal boosting may become a concern (up to this many kilometers).
What is 100?
This command-line tool checks if a network connection exists between two devices, and measures packet loss and latency.
What is the ping command?
These are packets that are too small, typically caused by network collisions or bad hardware.
What are Runts?
This is the process where data moves down through the OSI layers, adding headers and footers at each step.
What is Encapsulation?
This connector type with 3 pairs of wires is used for Category 3 telephone cabling.
What is RJ11?
These physical hardware components are used to convert electrical signals from Ethernet cables into light signals for transmission over fiber optic cables.
What are Transceivers?
This cable problem occurs when signal strength gets progressively weaker over distance.
What is Attenuation (or signal degradation)?
This performance issue happens when multiple devices fight over the same bandwidth or network resource at the same time.
What is Contention?
This OSI layer uses MAC addressing to establish communication on a local area network (LAN) and handles framing.
What is Layer 2 (Data Link Layer)?
This type of electrical cable is specifically designed for air circulation spaces in buildings (like above dropped ceilings) and resists fire with minimal toxic smoke.
What is Plenum cable?
This type of fiber optic cable has a larger core diameter (50 or 62.5 micrometers) that allows multiple paths for light, and typically uses LEDs as transmitters.
What is Multimode Fiber (MMF)?
This cable problem involves interference between wires inside the same cable or nearby cables, which is minimized by twisting pairs.
What is Crosstalk?
If data was changed or damaged due to a bad cable or electrical interference, we can run a CRC test, which stands for this.
What is Cyclic Redundancy Check?
Each layer of OSI has a PDU, which stands for
What is Protocol Data Unit?
This organization sets the primary networking rules and standards, such as 802.3 for Ethernet. (FULL NAME)
What is the Institute of Electrical & Electronics Engineers (IEEE)?
This fiber optic connector features a push-pull design with a square-shaped body.
What is an SC (Subscriber Connector)?
These special access points let you monitor network traffic without interrupting it, divided into passive types (that just copy traffic) and active types.
What are Taps (Test Access Points)?
This term describes the one slow component that holds an entire system back, whether it's CPU, RAM, disk, network, or software.
What is a Bottleneck?
This is the PDU for Layer 1.
What are Bits and Bytes?
This 10 Gigabit Ethernet standard over twisted pair copper cabling is designated by the IEEE specification name 10GBase-T.
What is Cat 6a or Cat 7?
This bayonet-style fiber optic connector uses a spring-loaded twisting mechanism.
What is ST (Straight Tip)?
This specific connection mistake happens when the transmit (TX) and receive (RX) pins are connected incorrectly on both ends of the cable.
What is Transmitter/Receiver Swapped?
There were four types of latency discussed in class, and some tools to identify the issue are to use ping and traceroute, use log files, use monitoring tools. Name at least 3 of the four types.
What are Network latency, Application latency, Disk latency, Database latency?