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LOP Alarm

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Dabdab

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Apr 20, 2010, 4:57:44 AM4/20/10
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Hi All,

I am getting LOP alarms on a VC4 connection, this is for both TU3 and
TU12 level, although this connection already have circuits on the
first TU3?

I am guessing there is misconnection the other end is Huawie from
diffrent provider. When a VC4 is TUG structured does it structure all
the TUG or just the ones having circuits?

Thanks

Bert Klaps

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Apr 20, 2010, 5:15:58 PM4/20/10
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On Apr 20, 10:57 am, Dabdab <dabda...@gmail.com> wrote:
> I am getting LOP alarms on a VC4 connection, this is for both TU3 and
> TU12 level, although this connection already have circuits on the
> first TU3?

You probably need to correlate the TU numbers for the which the LOP
defects´are declared with the VC-4 TUG structure configuration.

> I am guessing there is misconnection the other end is Huawie from
> diffrent provider. When a VC4 is TUG structured does it structure all
> the TUG or just the ones having circuits?

Well, the entire VC-4 will be structured, but since there are multiple
possibilities the exact structure is typically configured.
A substructured VC-4 consists of 3 TUG-3s, each of which can be
either contain one TU-3 or 21 TU-12s (simplifying for your case,
in general there are even more options).
This VC-4 structure needs to be identical at both ends of the VC-4.
If a TUG-3 is configured for TU-3 at node A and 21 TU-12s at the
other node B, node B will detect 21 TU-12 LOPs and node A will
detect TU-3 LOP.

Hope this helps,
Bert Klaps

Dabdab

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Apr 27, 2010, 6:55:43 AM4/27/10
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On Apr 21, 1:15 am, Bert Klaps <bertkl...@yahoo.com> wrote:
> On Apr 20, 10:57 am, Dabdab <dabda...@gmail.com> wrote:
>
> > I am getting LOP alarms on a VC4 connection, this is for both TU3 and
> > TU12 level, although this connection already have circuits on the
> > first TU3?
>
> You probably need to correlate the TU numbers for the which the LOP
> defects´are declared with the VC-4 TUG structure configuration.

We only use either TU3 or TU12 and on both I am getting LOP.

> > I am guessing there is misconnection the other end is Huawie from
> > diffrent provider. When a VC4 is TUG structured does it structure all
> > the TUG or just the ones having circuits?
>
> Well, the entire VC-4 will be structured, but since there are multiple
> possibilities the exact structure is typically configured.
> A substructured VC-4 consists of 3 TUG-3s, each of which can be
> either contain one TU-3 or 21 TU-12s (simplifying for your case,
> in general there are even more options).
> This VC-4 structure needs to be identical at both ends of the VC-4.
> If a TUG-3 is configured for TU-3 at node A and 21 TU-12s at the
> other node B, node B will detect 21 TU-12 LOPs and node A will
> detect TU-3 LOP.

I am not sure if the structure on the other side but as I mentioned we
only use TU3 or TU12 substructure.

I now with Huawie SDH they can play around with the signal so does any
one now if they can change the individual mapping of each TU12, is
this possible.


On anothe STM-1 link which has 63 E1 fully utilized but I am only
getting LOP on 6 circuits, from my experince if a circuit is not
mapped you get UNEQUIP alarm and not LOP!!!!

What causes LOP alarm is yet comming from the directly connected link
or it can come from further up stream?

Thanks

Huub van Helvoort

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May 3, 2010, 2:30:57 AM5/3/10
to
Hello Dabdab,

You replied:

> > > I am getting LOP alarms on a VC4 connection, this is for both TU3 and
> > > TU12 level, although this connection already have circuits on the
> > > first TU3?
>
> > You probably need to correlate the TU numbers for the which the LOP
> > defects´are declared with the VC-4 TUG structure configuration.
>
> We only use either TU3 or TU12 and on both I am getting LOP.

You have to check the VC-4 signal label, it should be set to "sub-
structured"

> > > I am guessing there is misconnection the other end is Huawie from
> > > diffrent provider. When a VC4 is TUG structured does it structure all
> > > the TUG or just the ones having circuits?
>
> > Well, the entire VC-4 will be structured, but since there are multiple
> > possibilities the exact structure is typically configured.
> > A substructured VC-4 consists of 3 TUG-3s, each of which can be
> > either contain one TU-3 or 21 TU-12s (simplifying for your case,
> > in general there are even more options).
> > This VC-4 structure needs to be identical at both ends of the VC-4.
> > If a TUG-3 is configured for TU-3 at node A and 21 TU-12s at the
> > other node B, node B will detect 21 TU-12 LOPs and node A will
> > detect TU-3 LOP.
>
> I am not sure if the structure on the other side but as I mentioned we
> only use TU3 or TU12 substructure.

Again, check the signal label of the VC-4 it should be set to "sub-
structured".

> I now with Huawie SDH they can play around with the signal so does any
> one now if they can change the individual mapping of each TU12, is
> this possible.

Only if the VC-4 is connected to a LO (VC-12/VC-3) cross-connect, here
the grooming can take place.

> On anothe STM-1 link which has 63 E1 fully utilized but I am only
> getting LOP on 6 circuits, from my experince if a circuit is not
> mapped you get UNEQUIP alarm and not LOP!!!!

Are all received signal lables indicating VC-12 (twelve) mapped, or is
there
one indicating VC-2 (two) mapped?

An open connection in the LO cross-connect will cause UNEQ.
If a signal is not connected, LOS will be detected on the input port
and AIS will be inserted, with a valid pointer.

> What causes LOP alarm is yet comming from the directly connected link
> or it can come from further up stream?

It can be caused by a wrong connection in any LO cross-connect further
up-stream.

Regards, Huub.

--
reply to hhelvooort with 2 'o's
================================================================
http://www.van-helvoort.eu/
================================================================
Always remember that you are unique...just like everyone else...

sanju

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May 5, 2010, 2:03:03 AM5/5/10
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> Always remember that you are unique...just like everyone else...- Hide quoted text -
>
> - Show quoted text -

One of the cause can be different structure at node A and B.
One side will be as VC3 higher order structured and other may be VC3
lower order (TUG3) structured. Both the VC4 facing each other should
be of same structure.

san

Huub van Helvoort

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May 6, 2010, 8:36:42 AM5/6/10
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Hello San,

You replied:

> One of the cause can be different structure at node A and B.
> One side will be as VC3 higher order structured and other may be VC3
> lower order (TUG3) structured.

The side that has VC-3 HO structured would be SONET equipment,
where the STS-1SPE is HO. The equivalent of VC-4 in SONET is
an STS-3c SPE.
The side that has VC-4 HO structure is SDH equipment, where VC-4
is HO.
What you describe would happen if you connect an OC-3 to an STM-1
(or OC-12 to STM-4, OC-3N to STM-N)

> Both the VC4 facing each other should be of same structure.

If the OC-3 is configured to have an STS-3c it should work, if it
is configured to have STS-1 only, strange effects will occur.

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