Network impairment unit for concurrent delay and packet queue impairments

Abstract

An impairment unit and method of emulating network impairments is disclosed. The impairment unit may receive network traffic and transmit impaired network traffic. Received packets may be stored in a memory physically partitioned into a plurality of memory blocks and logically partitioned into a plurality of buffers. At least one buffer may be associated with each of a plurality of predefined impairment classes. One or more buffer may be a limited-length queue. Memory blocks may be assigned to buffers on an as-needed basis. A classifier may determine respective impairment classes of the received packets. A number of memory blocks assigned to each limited-length queue may be limited to a respective predetermined maximum. An enqueue manager may store each received packet and associated metadata in the buffer associated with the respective impairment class. The enqueue manager may discard received packets if the associated limited-length queue is full.