Frames and Packets: In networking, data is divided into smaller units for efficient transmission. In the OSI and TCP/IP models, these units are known as frames and packets, respectively.
A frame is the data unit used at the data link layer (Layer 2) of the OSI model. It consists of a header, data payload, and trailer. The header contains control information such as source and destination addresses, while the trailer contains error detection bits like a checksum. Frames are transmitted between directly connected network devices, such as switches or Ethernet interfaces.
A packet, on the other hand, is the data unit used at the network layer (Layer 3) of the OSI model or the internet layer of the TCP/IP model. It consists of a header and a data payload. The header contains information such as the source and destination IP addresses, protocol information, and sometimes fragmentation details. Packets are used to route data across different networks. They are encapsulated within frames when traversing the data link layer.
Addressing: In network communication, addressing is used to identify the source and destination of data. There are different types of addresses used in various layers of the OSI and TCP/IP models.
Physical Address: The physical address, also known as the MAC (Media Access Control) address, is a unique
1.3 Latency, delay, speed test and Iperf
Latency refers to the time it takes for a packet of data to travel from one point to another in a network. It is the time delay between the moment a data packet is sent from a source and the moment it is received at its destination.
Delay is a broad term that encompasses different types of time delays in a network. Latency is one type of delay, but other types of delays may include queuing delay, processing delay, and transmission delay.
Speed test is a way of measuring the internet speed of a network connection. It typically measures the download and upload speed, as well as the latency of the network.
Iperf is a tool used for measuring the bandwidth and the performance of a network. It is a command-line tool that allows users to send and receive data across a network and measure the data transfer rate, packet loss, and latency. It is commonly used for network testing and troubleshooting.
1.4 Bandwidth and Throughput
Bandwidth and throughput are related but distinct concepts in networking.
Bandwidth refers to the maximum amount of data that can be transmitted over a network connection in a given time period. It is typically expressed in bits per second (bps), kilobits per second (Kbps), or megabits per second (Mbps).
Throughput, on the other hand, refers to the actual amount of data that is transmitted over a network connection in a given time period. It is the measure of the real data transfer rate achieved over a network connection.
Bandwidth is a measure of the capacity of a network, while throughput is a measure of the actual performance of the network. A network may have a high bandwidth but may not be able to achieve high throughput if the network is congested or there are other factors limiting the data transfer rate.
In summary, bandwidth is the theoretical maximum capacity of a network, while throughput is the actual data transfer rate achieved over a network.
