Nodal Delay

The Nodal Delay calculator computes the sum of the processing, queuing, transmission, and propagation delay in a network. 

INSTRUCTIONS:  Choose time units and enter the following:

• (Pc) Processing Delay
• (Qd)  Queuing Delay
• (Td)  Transmission Delay
• (Pg) Propagation Delay

Nodal Delay (N_d):  The calculator returns the Total Nodal Delay (d_nodal) is milliseconds(ms).  However, this can be automatically converted to numerous other time units (e.g. nano or microseconds) via the pull-down menu.

The Math / Science

Nodal Delay, also known as network latency, is the sum of the processing, queuing, transmission, and propagation delay in a network.  The formula for nodal delay is:

  N_d = Pc + Td + Qd + Pg

where:

• Nd = Nodal Delay (network latency)
• Pc = Processing Delay
• Td = Transmission Delay
• Qd = Queuing Delay
• Pg = Propagation Delay

The contribution of these delay components can vary significantly. For example, d_prop can be negligible (for example, a couple of microseconds) for a link connecting two routers on the same university campus; however, d_prop is hundreds of milliseconds for two routers interconnected by a geostationary satellite link, and can be the dominant term in d_nodal. Similarly, d_trans can range from negligible to significant.

Time Dependent Calculators

• Time required to process an amount of data at a specific data processing rate
• Amount of time required to transfer an amount of data over a different types of networks
• Number of items (unit-less) produced over time
• Length or distance processed (produce or consume) over time
• Area processed (produced, covered or consumed) over time
• Volume processed (produced or consumed) over time
• Weight or mass processed (produced or consumed) over time
• Speedup Factor (aka Amdahl's Law)
• Compute Data Storage Needed
• Network Propagation Delay

Telecommunications Calculators

• Propagation Delay Computes the delay between two routers based on their positions and a transfer rate.
• Nodal Delay: Computes the nodal delay based on the queuing, processing, transmission and propagation delay.
• End to End Delay Computes the end to end delay based on the number of nodes and the processing, transmission, and propagation delay.
• RF Velocity of  Propagation:  Computes the RF velocity based on the medium permittivity
• Transmission Delay: Computes the delay based on length of packet and transmission rate.
• Data Transfer Time Calculator Computes the time to transfer an amount of data based on the data transfer rate.
• Simplified Propagation Delay: Computes the delay between two router based on the distance and the transfer rate.
• Surge Impedance Loading: Computes the power loading of a transmission line.
• Amdahl's Law: Computes the total system speedup time based on the improvement of one portion.
• Signal-to-Noise Ratio (SNR) calculator: Computes a relative measure of the strength of the received signal (i.e., the information being transmitted) compared to the noise.
• Compute Data Storage Needed: Computes the approximate amount of data storage needed based on a period of time and a data rate.
• Network Propagation Delay  Computes the propagation delay based on the positions of two routers and the propagation speed.
• Shannon-Hartley Theorem: Computes the theoretical upper limit data rate of a channel based on the bandwidth, receiver strength and channel noise.
• Cable dB Loss Budget Computes db loss based on length of fiber run and number of connectors.
• Voltage Resolution (Analog to Digital) Computes the Voltage Resolution of a measured analog signal over the nominal range [VL , VH] with a specified number of conversion bits.
• Effective Isotropically Radiated Power (EIRP): Converts an EIRP measured in mw (milliwatt) to the unitless ratio of dBm (ratio of decibel to 1 milli-unit).
• Length of Cable with Sag: Computes the length of cable between pole accounting for the sag.