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IP178C/IP178C LF/IP178CH/IP178CH LF
Datasheet
2. Packet from WAN to LAN
2.1.
WAN port receives a packet with locked address PC3.
2.2.
IP178C/IP178CH adds a PVID equal to 2 and forwards the packet to CPU.
2.3.
CPU updates the DA, replaces PVID with 1 and sends it to IP178C/IP178CH.
2.4.
IP178C/IP178CH learns the SA.
2.5.
IP178C/IP178CH forwards the packet to port0 according to the DA.
PHY0
CPU
7 LAN ports (PVID=1)
MAC8
MAC0
PHY1
MAC1
PHY2
MAC2
PHY7
MAC7
DA
SA
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June 21, 2007
Copyright © 2004, IC Plus Corp.
IP178Cx-DS-R12
PC0
CPU
PVID
1
DA
SA
PC0
CPU
PVID
none
(5)
(3)
DA
SA
PC3
WAN
PVID
2
(2)
(4) Learning SA = CPU
locked SA=PC3
(1)
DA
SA
PC3
PVID
WAN
none
1 WAN ports (PVID=2)