Table of Contents
Advertisement
Technical Description
Figure 9
Priority/TC buffers
Each Ethernet interface has a separate egress buffer to handle temporary link
congestion. The egress buffers enable MINI-LINK PT 2010 to handle short
bursts without packet loss. The buffer is organized in different priority queues
or TCs. The buffer capacity is shared between the different egress priority
queues for an Ethernet port.
Scheduling
When an Ethernet port is congested the egress priority/TC buffers are filled up
with Ethernet frames. To empty the buffers a scheduler must serve the buffers
according to a predefined algorithm. MINI-LINK PT 2010 supports both Strict
Priority and Weighted Fair Queuing (WFQ) scheduling algorithms to empty
the egress priority/TC buffers.
The Strict Priority algorithm is typically used for delay sensitive traffic like voice,
video and sync packets. With Strict Priority, Ethernet frames in the buffer with
the highest priority are always scheduled first, for example, all Ethernet frames
with priority level 7 are scheduled before Ethernet frames with priority level 6.
20
Internal priority
Traffic class queue
7
6
Internetwork control
5
4
3
2
1
0
IEEE802.1Q-2005 Mapping
Network control
Video 10ms l.
Video 100 ms l.
Critical application
Excellent Effort
Best effort
Background
1/221 02-CSH 109 172/1-V1 Uen E | 2012-11-07
Empty 1st
Empty 2nd
Scheduling
Awailable BW
Empty last
14027
Advertisement
Table of Contents
