Subject: [PWE3] draft-ietf-pwe3-mpls-eth-oam-iwk-02.txt

From: "HENDERICKX Wim" <[email-masked]>
Date: Wed, 24 Mar 2010 21:45:53 +0100

Hi *,

My comment in the PWE3 meeting regarding using Interface status TLV for
ETH-oam interworking with PW was the following. Interface status TLV
identifies different values in 802.1ag:

isUp

Up

1

isDown

Down

2

isTesting

Testing

3

isUnknown

Unknown

4

isDormant

Dormant

5

isNotPresent

notPresent

6

isLowerLayerDown

lowerLayerDown

7

I believe we need to identify how the interface status TLV value should
be treated in the ETH OAM PW interworking. 

The reason why I am identifying this is that we could run into OAM loop
issues. E.g. this example

 CPE1 --- NTU1 ----  PE1 ---- MPLS ------PE2 ------ NTU2 ---- CPE2

1.    PE1/PE2 PW goes down

2.    PE1 send Interface status TLV : isDown to NTU1

3.    NTU1 brings down the interface to the CPE1

4.    NTU1 sends Interface Status TLV  = isNotPresent or isDormant back
to PE1

5.    PE1 treats this as a down event

We will never come out of the OAM loop in this example above.

What I think we should do in the draft is indicate for the different
values of Interface status TLV what to do regarding OAM interworking.

Cheers,

Wim

---

From: Ray Qiu <[email-masked]>
Date: Wed, 24 Mar 2010 14:02:35 -0700

Hi Wim,

If I understand correctly, only isUP and isDown are used in the draft to
indicate AC UP and DOWN events.  So in your scenario, isNotPresent or
isDormant will not be treated as a down event hence won't cause a loop.  I
guess some text can be added to the draft to explicitly indicate that.
Thanks.

Cheers,

Ray

  _____  

From: [email-masked] [mailto:[email-masked]] On Behalf Of
HENDERICKX Wim
Sent: Wednesday, March 24, 2010 1:46 PM
To: [email-masked]
Subject: [PWE3] draft-ietf-pwe3-mpls-eth-oam-iwk-02.txt

Hi *,

isUp

Up

1

isDown

Down

2

isTesting

Testing

3

isUnknown

Unknown

4

isDormant

Dormant

5

isNotPresent

notPresent

6

isLowerLayerDown

lowerLayerDown

7

I believe we need to identify how the interface status TLV value should be
treated in the ETH OAM PW interworking. 

1.     PE1/PE2 PW goes down

4.     NTU1 sends Interface Status TLV  = isNotPresent or isDormant back to
PE1

What I think we should do in the draft is indicate for the different values
of Interface status TLV what to do regarding OAM interworking.

Cheers,

Wim

---

From: "HENDERICKX Wim" <[email-masked]>
Date: Wed, 24 Mar 2010 22:06:01 +0100

Ray, indeed this is what I was after. Have some text which indicates
what is expected with each of the interface status values.

Thanks

Wim

From: Ray Qiu [mailto:[email-masked]] 
Sent: woensdag 24 maart 2010 22:03
To: HENDERICKX Wim; [email-masked]
Subject: RE: [PWE3] draft-ietf-pwe3-mpls-eth-oam-iwk-02.txt

Hi Wim,

If I understand correctly, only isUP and isDown are used in the draft to
indicate AC UP and DOWN events.  So in your scenario, isNotPresent or
isDormant will not be treated as a down event hence won't cause a loop.
I guess some text can be added to the draft to explicitly indicate that.
Thanks.

Cheers,

Ray

________________________________

Hi *,

isUp

Up

1

isDown

Down

2

isTesting

Testing

3

isUnknown

Unknown

4

isDormant

Dormant

5

isNotPresent

notPresent

6

isLowerLayerDown

lowerLayerDown

7

1.    PE1/PE2 PW goes down

Cheers,

Wim