High Performance Two Port 10/100 Managed Ethernet Switch with 32-Bit Non-PCI CPU Interface
Datasheet
Packet is from Host
Packet is Tagged
Packet is IPv4
Packet is IP
VL Higher Priority
Use Precedence
Use IP
VLAN Enable
6b
IPv4(TOS)
IPv6(TC)
Programmable
DIFFSERV Table
3b
3b
IPv4 Precedence
3b
Priority
Calculation
flow priority
3b
Programmable
Port Default
Table
2b
Source Port
3b
VLAN Priority
Figure 6.7 Switch Engine Ingress Flow Priority Selection
The ingress flow calculation is based on the packet type and the device configuration as shown in
Figure 6.8.
Get Flow Priority
Y
Packet from Host
N
N
VL Higher
Priority
Y
Vlan Enable &
Packet is
Y
Tagged
N
Y
Packet is IPv4/v6
& Use IP
N
Vlan Enable &
Packet is
Tagged
Y
Y
Packet is IPv4
N
N
Y
N
Use Precedence
Flow Priority =
Default Priority[Source
Port]
Flow Priority =
IP Precedence
Flow Priority=
DIFFSERV[TOS]
Flow Priority =
DIFFSERV[TC]
Flow Priority=
VLAN Priority
Get Flow Priority Done
Figure 6.8 Switch Engine Ingress Flow Priority Calculation
SMSC LAN9312
Revision 1.2 (04-08-08)
DATA7S3HEET
SMSC [ SMSC CORPORATION ]
