TNETX3270
ThunderSWITCH 24/3 ETHERNET SWITCH
WITH 24 10-MBIT/S PORTS AND 3 10-/100-MBIT/S PORTS
SPWS043B – NOVEMBER 1997 – REVISED APRIL 1999
42 POST OFFICE BOX 655303 DALLAS, TEXAS 75265
Unknown
Multicast
Destination
Start
Known
VLAN?
Source Port = 1 in.
VLANnports?
Yes
Destination
Address
Found?
Yes

Unkmem

Key:

interrupt

No
Yes No
No

UnkVLAN

Destination
is
Multicast?
Destination
is
Multicast?
Yes Yes
Yes
NoNo
Destination
Locked
Bit = 1?
Source Port
Blocked by
RxUniBlockPorts
and Dest.
Nblck=0?
No
Yes
Yes
Yes Source Port
Blocked by
RxMultiBlockPorts
and Dest.
Nblck=0?
Source Port
Blocked by
RxMultiBlockPorts?
Yes
Source Port
Blocked by
RxUniBlockPorts?
Destination
is
Multicast?
Yes
Yes
Source Port
Blocked by
RxMultiBlockPorts or
UnkVLAN=0?
No
No No No No No
Port Routing
Code = Port Code
From Records
Port Routing
Code = Port Vector
From Records
Port Routing
Code =
UnkMultiPorts
Port Routing
Code =
UnkUniPorts
Port Routing
Code =
UnkVLANPort
AND Port Routing
Code With VLAN
VLANnports Code
Include UplinkPort
in Port
Routing Code
Destination
Cuplink Bit
Set?
No
To A
(Continued) To B
(Continued)
Yes

statistic

Unknown
Unlcast
Destination
Set Port Routing
Code to 0
To C
(Continued)
Figure 9. Frame-Routing Algorithm