# What is bittime?

Bit time is a computer networking term that measures how long a pulse or bit takes to travel from a transmitter to a receiver to produce a specific network data rate. It is sometimes confused with other terms such as bit rate or baud rate, which is the total number of bits per second (bps) transmitted, and slot time, which is the amount of time it takes for a pulse to travel the length. longest of a network medium. Bit timing, however, only calculates the ejection of a bit, and instead of focusing on the network medium, it looks at how that bit is transmitted out of a network interface card (NIC) at a given speed, such as 10 Mbits / s.

man holding computer

Many people have heard the term “bit” in reference to computers, but may not know exactly what it is or how it is used. A bit is a single binary number, either zero or one, used in network transmission to indicate the amount of voltage that pulsates in a circuit. So the bit time is looking at one of these pulses and how fast it responds to an instruction to leave the NIC. As soon as the logical link control layer 2 sublayer receives a command from the operating system, the bit time measurement begins, calculating how long it takes for the bit to be ejected from the NIC. The basic formula for this is: Bit time = 1 / NIC speed.

Some common bit time measurements are 10 nanoseconds for Fast Ethernet and 100 nanoseconds if the given speed is 10 Mbits/sec for the NIC. The bit time is 1 nanosecond for gigabit Ethernet. Put another way, to transmit 1 Gbps of data, it only takes 1 nanosecond. Overall, therefore, the higher the data rate, the lower the bit rate.