RDI vs RFI

[zsq...@my-deja.com]

Group,

What is the difference between a RDI and RFI? From my research, I
cannot find a byte that actually has an RFI signal, but only the RDI.
However, they say that RFI is derived from an RDI?

Can some pls elaborate on how RFI is formed>

Thanks.

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Before you buy.

[Conductor]

RFI is part of the V5 byte (Bit4) although in SDH as far as I'm aware it is
not supported (used).
It only becomes active after a defect has been present for a defined time.

A RDI (Remote Defect Indication) will be induced in the return path of an
upstream LOS for example and if this fault persists for the defined time
then a RFI will be raised.

RDI is also supported on MS section etc but don't have the time to give full
details.

I hope this is accurate and helps.

<zsq...@my-deja.com> wrote in message news:8tpedh$22g$1...@nnrp1.deja.com...

[zsq...@my-deja.com]

Thanks for the response. But one point of clarification...you
say "defined period of time" then the RFI is raised. Now...(on
section/line layer) is this RFI a specific byte? Or is it just a
condition on the side that receives the RDI for a period of time.

Thanks.

In article <8tpj90$1ba$1...@sshuraaa-i-1.production.compuserve.com>,

[Conductor]

I've just had a look at some notes (SDH) and MS-RDI/AIS are supported in
K1/2 bytes for APS but don't see any mention of RFI.
VC4/3 path G1 byte supports RDI but no mention of RFI.
I still think it is supported in SONET and may be included later in SDH.

<zsq...@my-deja.com> wrote in message news:8tpvvv$ild$1...@nnrp1.deja.com...

[Huub Van Helvoort]

Hi,

RDI = Remote defect Indication sent from the sink to the source can be used
for near-end performance monitoring.

RFI = Remote Failure Indication, only used for byte-synchronous mapped DS1
(1.5 Mbit/s) signals according to G.707.
This is send from sink to source after a detected defect exists for a
certain amount of time (so yes, it can be derived from RDI)
Was (is?) used for carrier alarming (to save stable calls).

Cheers, Huub.

> What is the difference between a RDI and RFI? From my research, I
> cannot find a byte that actually has an RFI signal, but only the RDI.
> However, they say that RFI is derived from an RDI?
>
> Can some pls elaborate on how RFI is formed>

------------------------------------------------------------------------
Always remember that you are unique... Just like everyone else.

[Byrautor]

Please
Your exchanges interest me, I write in french on the SDH and I give some
courses in schools of engineers.
The topic is vast and I am anxious to remain modest.

I can give some information:
One finds some answers in:
English language:
in the book of TESTS SOLUTIONS FOR DIGITAL NETWORKS, Roland Kiefer, at
Hüting Verlag Heidelberg (advisable by Wandel and Golterman) ISBN
3-7785-2527-1, page 205.
Sonet a guide to Synchronous Optical Network , Walter J. Goralski,
McGRAW-HILL ISBN 0-07-024563-0
Understanding Sonet/SDH standards and Applications, Ming-Chwan Chow, ANDAN
PUBLISHER ISBN 0-9650448-2-3

French language: Les Réseaux Synchrones étendus PDH et SDH ; The Networks
Synchronous extended PDH and SDH of Gérard Bouyer, at HERMES, ISBN
2-86601-644-0, http://www.hermes-science.com, page 181,

For the VC-LO, he/it seems that 2 RDI exist (- LP, Low Path), the old RDI
that is b8 of V5 and a RDI improved that is represented by b5, 6, 7 of K4
and give more information on the failing.
For me, RFI b4 of V5 indicates that the partner in dialogue functions but
receives some information erronnées (false).
In LP, RDI can be generated back in the path by a failing of circuit, he
indicates a failing of the path back as CONDUCTOR said it.

________________________________________________________________________

<zsq...@my-deja.com> a écrit dans le message :
8tpedh$22g$1...@nnrp1.deja.com...

[zsq...@my-deja.com]

This discussion is good. The spec indicates that RFI is "derived" from
RDI (For Line segment).
However, there IS NO RFI byte relayed for the LINE only for the PATH
and VT.

Does anyone concur with that?

In article <8tpedh$22g$1...@nnrp1.deja.com>,