Alcatel Carrier Internetworking Solutions 6648 - Manual (Page 364)

Unknown Destination
page -40 OmniSwitch Troubleshooting Guide September 2005
5
Classify Special DA
DA is router MAC DA is IGMP DA is IPMS DA is STP multicast
(BPDU)
6
7
8
DA PCAM
lookup,
known ?
S/W Slow Path Routing L3
FDB?
Send to Destination
Send to Default
Gateway
N N
Y
Y
Provides a
Next_Hop_Header_Cache index
NHHC index provides QID,
ReQID & PDI Performs NAT, MAC-DA, TTL,
SLB and Fragment modifications 4
L3 Packet Walk
6
DA is IGMP
S/W
QID set
to either
multicast
within
the vlan
or drop
ReQID
Sent to
S/W for
processing
7
DA is IPMS
L3 DA lookup
Pass? New IPMS
group
S/W
L3-DA, L3-SA,
pport, sGID
lookup, Pass ?
Flow not
known
S/W
Set QID, ReQID, PDI &
header_cache info
Access PDI
En Queue the
data to the
final
QID=511
(multicast
Queue on
Nantucket)
Nantucket sends the packet to all egress
Coronado within the same
multicast/vlan id Egress Coronado sends to all the ports in the
same vlan, strips tag if necessary
N
N
Y
Y
IGMP/IPMS