Description: When limited space is left in Tx buffer, only the highest priority packets are accepted. This in turn can create a situation in which one port tries to send a packet and never gets its chance to be accepted. In order to prevent it the destination port counts the successive number of tries of the low priority port, and when a certain (8) number is reached, it accepts the packet anyhow. The value on(1) defines the retry parameter for the priority level mechanism.