# Frame Relay CIR and this article

Mar 5th, 2007

http://www.garykessler.net/library/framerelay_cir.html

I am aware that these concepts have been explained, but I got confused when I read the article below :

[quote]

It is important to understand that CIR is not an instantaneous measurement of transmission, but an average rate over time. Thus, a 16-kbps CIR does not mean that a user is limited to a transmission rate of 16 kbps, but that the user will not transmit more than 16,000 bits in a second (or 32,000 bits in two seconds, etc.).

[/quote]

[quote]

If Bc = 16,000 bits and Tc = 1 second, for example, the CIR is said to be 16 kbps. However, a Bc = 160,000 and Tc = 10 also yields a CIR of 16 kbps. The latter case, however, will allow a more erratic (bursty) traffic pattern.

[/quote]

1- I could not understand in the first quote what he means when he says : "does not mean that a user is limited to a transmission rate of 16 kbps" ?

2- If Bc is 16000 (3 zero) and the Tc=1 or Bc is (4 zero) and the Tc=10,,,,I can not see any difference ?