Wavetronix Click 342 (lean managed ethernet switch) (CLK-342) Manuel d'utilisateur télécharger pdf (Page 23)

22 CHAPTER 1  CLICK 340/341/342 MANAGED SWITCHES

e switch controller in the managed switch forwards received packets to one of the receive

queues according to the following decisions:

 Bridge Protocol Data Unit (BPDU) packets are always assigned to the high-priority

queue.

 Packets with unknown unicast addresses are always assigned to the low-priority queue.

 Packets are assigned to the high-priority queue if the priority from the VLAN/prioriti-

zation tag is mapped to the “high” level (default priority 4 to 7).

 e internal port priority “high” results in priority level 7 handling, i.e., the basic set-

tings for data packet assignment to the high-priority queue are made.

 All residual data is assigned to the low-priority queue.

Strict Priority

e switch supports two priority queues for adjusting the internal packet processing se-

quence (trac classes according to IEEE 802.1D). Data telegrams that are received are as-

signed to these classes according to their priority, which is specied in the VLAN/prioriti-

zation tag:

 Data packets with values between 0 and 3 in the priority eld are low priority (default).

 Data packets with values between 4 and 7 in the priority eld are high priority and

transmitted via the switch.

e managed switch uses strict priority for transmitting data telegrams. First, all high-

priority data packets are assigned. Once these are forwarded, low-priority telegrams are

assigned.

is function prevents delays in high-priority data transmission because of the large vol-

umes of low-priority data trac. Low-priority trac is rejected when the memory or data

channel is overloaded.

1 2 ... 18 19 20 21 22 23 24 25 26 27 28 ... 75 76

Pas de commentaire

Wavetronix Click 342 (lean managed ethernet switch) (CLK-342) Manuel d'utilisateur Page 23