S Layer 2 Managed Switch User Manual
陈泽科技有限公司
www.stephen-tele.com
24
can add all member ports of trunk group to some specific 802.1Q VLAN domain broadcast.
Notice:
Trunk and port bandwidth, port control influence:
Ports that configured to trunk member can not open port bandwidth control and can not be configured to control port and
vice versa.
Trunk bandwidth calculation:
When trunk consist of four full-duplex 100Mbps ports, since for each port up and down are 100Mbps, every port’s bandwidth
will be 200Mbps. They are aggregated together via trunk technology to form a total bandwidth of 800Mbps (200MbpsX4).
Trunk path selecting mode:
There are 3 mode of trunk selection in
S:
SMAC, DMAC and XOR. Selection mode determines the selection physical
chain of some specific packet that is sent from TRUNK logical port. If SMAC mode is selected, select mode select the path
according to source MAC address of data package. If DMAC mode is selected, select mode select the path according to
destination MAC. If it is XOR mode, select mode selects the path according to the value that via different calculation from
source MAC and destination MAC.
S
’s select mode is not based on some specific trunk group. If ever you set a specific trunk group selection mode, this
mode will take effect to all trunk group.
4.6 QoS management
This switch allows configuring port priority, ToS priority and 802.1p priority. It provides data frame Tag remap function under
802.1p priority mode.
4.6.1 Priority configuration
Priority mode: there are Disable priority, port-based priority, ToS priority and 802.1p priority modes. 802.1p priority is
only effective under 802.1 Q Tag VLAN mode.
Priority control rule: there are WRP and WRR options. When priority rule is WRR, switch can forward data
frame proportionably according to data frame priority. When priority rule is WRR, switch will forward data
frame with highest priority then forward data frame with other priority.
802.1p priority remap mode: this function can be opened only under 802.1p priority mode.
4.6.2 Port priority table
There are only 2 choices of port priority: low and highest. When priority mode is Port-Based Priority, all frame get from this
port will be assigned to low or highest priority. Port priority table can configure this port default priority Tag. All untagged
frame that receive from this port will be assigned this default priority tag. This function is only effective under 802.1p priority
mode.
4.6.3 ToS priority
ToS (Type of Service) is an 8bit byte of IP header. It contains one 3bit priority sub section (0-7), one 4bit ToS sub section and
1bit unused bit and set to 0. 4bit ToS represents: smallest delay, biggest capacity, highest reliability and least expense. Only
1bit can be set in this 4bit. If all 4 bits are set to 0, it means general service.
This switch has ToS priority function. D-Type represents smallest delay. T-Type represents biggest capacity. R-Type represents
highest reliability. M-Type represents least expense. E.g. if we configure D-Type 2 priority as highest, when switch receive IP
header with ToS section’s priority sub section is 2. When ToS sub section set smallest delay bit packet, it will assign this packet
priority as highest.
