Goal: study of the time properties of an EF stram when best-effort traffic is run concurrently. This behaviour is compared to the case where the time properties of a single EF stream are analysed.

Comments:

• Figure 1 shows the evolution of one-way delay over time for different packet sizes.
  One-way delay oscillates periodically, especially for packet sizes larger than 1024 bytes.
  For smaller packets of 64 or 128 bytes delay decreses during the initial transient phase.
  For smaller packet sizes (64 and 256 bytes) ipdv is higher, up to 11 and 14 msec respectively. This could be due to the fact that when an EF packets is queued in the transmit ring, one or more best-effort packets are sitting in the queue and the number of BE packets varies. On the other hand, for larger packet sizes the ipdv is around 9 msec, a time closer to the transmission time of one best-effort packet (1000 bytes) at 1 Mbps. We could guess that in this case on the average fewer best-effort packets sit in front of an EF packet. Since 1 particle corresponds to 512 bytes, both 1 EF and 1 BE packets occupy 2 slots. On the whole, in this test the tx ring can store up to 20 packets. Figure 4 and figure 5 show in detailed the ipdv for several packet sizes.