Network Security and Connectivity Basics

A network that spans a wide geographical area, connecting LANs.

A worldwide network of networks, connecting LANs and WANs.

A private network within an organization, accessible only to authorized members.

A network that allows authorized external users to access an organization's internal network.

High-speed internet access using cable television infrastructure.

High-speed internet access using phone lines.

Internet access via mobile phone networks.

Internet access via satellite.

Using interconnected technology in home appliances, allowing them to communicate with each other and other systems.

Connecting devices to a local area network (LAN) through electrical outlets.

Internet access for homes/businesses using cellular technology, common in rural areas.

Potential dangers to a network, including viruses, worms, and malicious attacks.

Threats to a network from outside sources, such as viruses, malware, and cyberattacks.

Security risks from within a network, such as employee misuse or lost devices.

Protecting network data and systems from various threats and ensuring smooth operation.

Methods and technologies for improving network security, including antivirus software, firewalls, etc.

Networks have a sender (source), receiver (destination), and path (channel) for communication.

Rules governing how communication happens between devices in a network.

Protocols need sender/receiver, common language, speed/timing, and confirmation mechanisms.

Converting information into a transmittable format.

Converting a coded message back to its original form.

Structuring messages to adhere to network standards.

Controlling message flow rates and response times.

Computer networks require message encoding, formatting, size, and timing rules for proper communication.

The Physical Layer establishes wired or wireless connections to a network, connects devices using NICs, and transports data bits across network media.

The Physical Layer accepts data frames from the Data Link Layer, encodes them into signals for transmission, and then the next device in the path receives and decodes the signals back into a frame.

Physical Layer Standards define the physical components, media, connectors, encoding and signaling methods used for data transmission across a network.

Bandwidth is the capacity of a medium to carry data, measured in bits per second (bps).

Latency is the time it takes for data to travel from one point to another, including delays.

A cable with a central copper conductor surrounded by insulation, a woven copper braid for shielding, and an outer jacket. Commonly used for cable TV and older internet connections.

Unshielded Twisted Pair cabling uses 4 pairs of twisted copper wires encased in a plastic sheath. The twisting helps reduce electromagnetic interference.

UTP uses opposite polarity in each wire pair to create cancellation. This, along with varying twist rates, reduces interference.

TIA/EIA defines standards for UTP cabling, covering cable types, lengths, connectors, termination, and testing. They also establish electrical standards like Category 5 or 6, indicating performance levels.

A common connector used to terminate UTP cables. It has 8 pins for connecting to network devices.

A UTP cable used to connect different types of devices such as a computer to a router or a switch.

A UTP cable used to connect similar devices, like two computers directly without a switch or router.

Uses thin glass strands that transmit data via light pulses, offering high bandwidth, long distances, and immunity to electromagnetic interference.

Models that divide network operations into functional layers, simplifying design and promoting interoperability.

A 7-layer model that defines network functions from physical connections to application services.

A 4-layer model that focuses on internet connectivity and emphasizes protocols like TCP and IP.

The process of adding protocol information to data as it travels down the network layers.

Breaking large messages into smaller units called segments for efficient transmission.

Data units with specific protocol information added as they move through different network layers.

Data is wrapped with protocol information from each layer as it moves down the network stack.

Removing protocol information from data as it moves up the network stack.