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Tnetx4090 thunderswitch ii, Switch, Figure 12. frame-routing algorithm – Texas Instruments THUNDERSWITCH II TNETX4090 User Manual

Page 51

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TNETX4090

ThunderSWITCH II

9-PORT 100-/1000-MBIT/S ETHERNET

SWITCH

SPWS044E – DECEMBER 1997 – REVISED AUGUST 1999

51

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

No

No

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 12. Frame-Routing Algorithm