User manual

Startup and Functions

7278_en_01 PHOENIX CONTACT 2-9

Flowchart for "Learning Addresses" Using the Example of Unicast Addresses

Figure 2-5 Flowchart for "learning addresses"

2.2.4 Prioritization

The switch supports two priority queues for adjusting the internal packet processing

sequence (traffic classes according to IEEE802.1D). Data telegrams that are received are

assigned to these classes according to their priority, which is specified in the

VLAN/prioritization tag:

– Data packets with values between "0" and "3" in the priority field are low (default)

priority

– Data packets with values between "4" and "7" in the priority field are high priority and

transmitted via the switch

Switch receives a

frame at port 1

The assigned port

is receive port

(port 1)

Search for destination

address in the

address table. Found?

Ye s

Send frame via

all ports except

port 1 (flooding)

Check which port

the address

is assigned to.

The assigned

port is port 3

Discard frame

Send frame

via port 3

Enter address with

time stamp (including

port assignment)

Backward learning -

Search for source address

in the address table

Address

found

Address

not found

Update

time stamp

72780014