snPortCARLimit is the normal burst size in bytes, specifying how much traffic is guaranteed to be transported at the average rate during a committed time interval before some traffic starts exceeding the rate limit. Admins tune this to allow short traffic bursts above the average rate without penalty, accommodating naturally bursty application traffic. For example, an admin allowing brief bursts for a bursty application while still enforcing a long-term average via snPortCARRate would set snPortCARLimit to a value larger than a single packet but smaller than the extended burst limit.