Computer Network Concepts and Models

A switch operates in the Data Link layer (Layer 2) of the OSI model.

A router operates in the Network layer (Layer 3) of the OSI model.

A command used to test network connectivity, verifying a device is reachable.

Used to display current TCP/IP network configuration of a computer.

A bit is the data unit used on the physical layer.

The network layer in the OSI model corresponds to the internet layer in the TCP/IP model.

UTP cables contain 4 pairs of wires.

Twisting wires in twisted-pair cables reduces cross-talk interference and improves signal quality.

A Media Access Control address is a unique 48-bit identifier for network interfaces.

A MAC address is a physical address assigned to devices on a network.

A network interface controller (NIC) is identified by a unique MAC address.

A method for data transmission where specific bytes (flags) mark the beginning and end of a data frame.

If the data contains a flag byte, an escape byte is inserted to avoid misinterpretation.

A special byte used in byte stuffing to avoid confusion between data bytes and framing control bytes.

A data framing technique using flag bytes to mark the start and end of a frame and byte stuffing to avoid errors.

Converting a transmitted data sequence with byte stuffing back to the original form.

ARP (Address Resolution Protocol) translates IP addresses into physical MAC addresses. This allows devices on a local network to communicate with each other.

In Slotted ALOHA, collisions can only occur at the beginning of a time slot. This is because all devices synchronize their transmissions to the start of the slot.

Slotted ALOHA has a higher maximum efficiency compared to ALOHA. This is because the time slots help reduce the chances of collisions.

The exponential back-off algorithm is used in CSMA/CA to delay transmission attempts after a collision. It increases the delay exponentially with each subsequent collision.

In FDMA, if a frequency band is assigned to a station but has no data to transmit, it remains idle. The frequency band isn't removed or shared.

In TDMA, each station is allocated a fixed-length time slot in which it can transmit data. These time slots are distributed among all stations.

The IP v4 header checksum is calculated using only the IP v4 header, not including the data payload.

To convert an IP address to binary, convert each octet (group of 8 bits) to its binary equivalent.

An IP address is split into two parts: a network portion and a host portion, identifying the network and specific device.

The IP address 0.0.0.0 is a special address used for different purposes, including network default routing or indicating an unknown source.

The IP address 127.0.0.1 is the loopback address used to test network connectivity within the same device.

Routers use a First-In-First-Out (FIFO) queuing model for packet scheduling, meaning packets are processed in the order they arrive.

The Time-To-Live (TTL) field in the IP v4 header sets a limit on how many hops a packet can traverse.

The IP v4 header is always 20 bytes in size.

A dynamic routing protocol that calculates the shortest paths between network nodes. It uses distance vectors, which are updated based on information exchanged between neighboring nodes.

A data structure used in Bellman-Ford routing that represents the shortest distances from a particular node to all other nodes in the network.

A potential issue in Bellman-Ford routing where, due to network loops or incorrect information, the algorithm might falsely calculate infinite distances.

Routing within an Autonomous System (AS), a group of networks under a single administrative domain.

Routing between different Autonomous Systems (ASs), allowing communication across different administrative domains.

A distance-vector routing protocol commonly used for intra-AS routing. It uses a hop count as a metric to determine the shortest path.

A link-state routing protocol that calculates shortest paths based on link costs. It is used for intra-AS routing.

A path-vector routing protocol primarily used for inter-AS routing. It exchanges routing information between different Autonomous Systems.

TCP (Transmission Control Protocol) is a reliable, connection-oriented protocol that ensures data is delivered in order and without loss. It's widely used for applications like email (SMTP) and file transfer (FTP).

The Transport Layer in the OSI model is responsible for end-to-end data transfer between applications running on different hosts. It ensures reliable and ordered delivery of data segments.

The Transport Layer uses both TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) for communication over the internet. TCP is connection-oriented and reliable, while UDP is connectionless and best effort.

FTP (File Transfer Protocol) uses TCP (Transmission Control Protocol) as its underlying transport protocol, enabling reliable and ordered data transfer for file exchange.

TCP is a connection-oriented protocol that establishes a connection using a three-way handshake. It receives data from applications as a single stream, ensuring data integrity and sequence.

A socket is an endpoint of a communication flow between two processes running on different hosts. It acts as the interface for data exchange between applications.

Winsock is a socket-style API (Application Programming Interface) used in Windows operating systems to provide a common interface for network programming.

UDP (User Datagram Protocol) offers low overhead compared to TCP, making it efficient for applications that don't require guaranteed delivery or ordered data, like streaming or gaming.