L2 transparency – VLAN

../../_images/trsp-vlan.png

This task verifies VLAN transparency, that is, that packets with user-specified VLAN tag, VLAN priority (PCP), and DSCP are not modified by the network.

Test procedure and fail criteria

VLAN transparency

In this part of the test, five frames are generated for each of the VLANs in the table below. The frames are correctly created Ethernet frames with a VLAN header and an IP payload.

The test fails if not all frames are received, or if any of the VLAN ID, p-bits, or IP DSCP is modified.

VLAN ID

p-bits

DSCP

0

0

0

12

4

20

99

3

15

150

6

30

517

5

25

1033

1

5

1434

2

10

1800

0

0

2047

7

35

4094

6

30

4095

7

35

Q-in-Q transparency

In this part of the test, Q-in-Q is tested with Ethertypes 0×8100, 0×88a8, 0×9100, and 0×9200 for the outer VLAN. For each Ethertype, a number of outer and inner VLAN ID combinations are used; for each such combination, five frames are generated. The frames are correctly created Ethernet frames with a Q-in-Q header and an IP payload.

The test fails if not all frames are received, or if any of the VLAN ID (inner/outer), p-bits, or IP DSCP is modified.

Outer VLAN ID

Outer p-bits

Inner VLAN ID

Inner p-bits

DSCP

0

0

4095

7

0

13

5

4083

2

25

100

4

3995

3

20

151

7

3944

0

35

518

6

3577

1

30

1034

2

3061

5

10

1435

3

2660

4

15

1801

1

2294

6

5

2048

0

2047

7

0

4095

6

1

7

35

Limitations

This test can only run on physical interfaces (not on VLANs or bridges).

Regarding use of the Test Agent management interface for this test, see here.

Parameters

General

  • Sender: The sender Test Agent interface.

  • Receiver: The receiver Test Agent interface.

  • Wait for ready: Time to wait before starting this test step. The purpose of inserting a wait is to allow all Test Agents time to come online and acquire good time sync. Min: 1 min. Max: 24 hours. Default: “Don’t wait”, i.e. zero wait time.

Result metrics

  • Pass/fail on VLAN transparency

  • Pass/fail on Q-in-Q transparency