Korenix JetNet 3008 v3, Руководство пользователя

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5. Packet forwarding and filtering ability
The JetNet 3008/ JetNet 3008f features packet filtering functions for
broadcast packet control protection and QoS. Both of features can provide
more graceful performance in a crowded network by traffic filtering and
prioritize.
This session will introduce the principle of traffic control and forwarding
precedence, includes Broadcast control and Quality of Service.
5-1. Broadcast Control
The JetNet 3008 or JetNet 3008f begins to drops broadcast packets which
DA ( destination address) are equal to FF:FF:FF:FF:FF:FF if the received
broadcast packets are more than the threshold – 198 packets/ per second
at 100Mbps or 19 packets / per second at 10Mbps link speed.
All of ports are enabled with this function without any configuration to
provides better network performance and prevent network congest with
the flooding of broadcast packets.
5-2. Quality of Service
The JetNet 3008 / 3008f supports frame type priority function, high priority
packet will be queued to high priority queue to share more bandwidth. The
ratio of bandwidth of high priority and low priority queue is 8:1. After 8 high
priority packets is progressed, then 1 low priority.
Both of JetNet 3008 and JetNet 3008f can examine the specific bits of
VLAN Tag and TCP/IP TOS of IPv4 and IPv6.
IEEE 802.1Q tag based CoS
The JetNet 3008/ 3008f will examine the 3 bits of priority field carried by a
VLAN tag and map it to the corresponding priority. A packet with priority
field ranging from 0 to 3 will be treated as a low priority packet, and will be
stored in low priority queue. A packet with priority field ranging from 4 to 7
will be treated as a high priority packet, and will be stored in high priority
queue.