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  • About OPUflex(GFP) and ODUflex(GFP)

    From arstpt.michelh@gmail.com@21:1/5 to All on Fri Feb 12 06:43:59 2016
    Bonjour Huub,

    I don't feel comfortable with OPUflex(GFP) and ODUflex(GFP).

    We can map ETH frames, for example, 2 Gbit/s in the OPUflex(GFP)payload.

    I would suppose we have an overhead attached to this payload. What is it?

    The OPUflex(GFP) is associated to ODUflex(GFP).

    - It seems we don't have an overhead at this step.
    - Is ODTU2.3 payload exactly similar to this ODUflex(GFP)?

    Cordialement,
    Michelot

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  • From Michelot@21:1/5 to All on Sat Feb 13 02:49:49 2016
    Bonjour Huub,

    I am really sorry to waste your time, the previous post cannot be modified. After writing it, suddendly I found some elements.

    I would suppose we have an overhead attached to this payload. What is it?

    There is no exemption in the format. The OPUflex and ODUflex formats are same as OPUk and ODUk. Only periodicity differ.

    For OPUflex, we can see section 17.4 : mapping of GFP frames into OPUk (k=0,1,2,3,4,flex). The OPUk unities have a general format.

    - It seems we don't have an overhead at this step (for ODUflex).

    It was my confusion by interpreting the figure 7-5. In fact, the writing of "ODU OH" means "ODUflex OH". Probably there was no sufficient place to note this. Of course, after understanding, we see the relation just below "ODU (ODUflex)"! I have problems
    of view.

    - Is ODTU2.3 payload exactly similar to this ODUflex(GFP)?

    I see that the nominal bandwidth of ODTU2.ts for example is the TS bandwidth in OPU2. The numeric value in table 7-7 is rounded.

    On the other hand the value of nominal bandwidth of ODU2.ts is exact, not rounded, a little bit lower than ODTU2.ts.

    It is mentionned that this exact value is to easy the clock generation. Have you pleased a word for that.

    Thousand forginesses,
    cordialement,
    Michelot

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  • From Huub van Helvoort@21:1/5 to You on Sat Feb 20 00:08:07 2016
    Bonsoir Michelot,

    You wrote:

    I am really sorry to waste your time, the previous post cannot be
    modified.

    Indeed, that is impossible on usenet, even deleting the post is
    difficult.

    After writing it, suddendly I found some elements.

    Very good.

    I would suppose we have an overhead attached to this payload. What
    is it?

    There is no exemption in the format. The OPUflex and ODUflex formats
    are same as OPUk and ODUk. Only periodicity differ.

    Correct.

    For OPUflex, we can see section 17.4 : mapping of GFP frames into
    OPUk (k=0,1,2,3,4,flex). The OPUk unities have a general format.

    Indeed.

    - It seems we don't have an overhead at this step (for ODUflex).

    It was my confusion by interpreting the figure 7-5. In fact, the
    writing of "ODU OH" means "ODUflex OH". Probably there was no
    sufficient place to note this. Of course, after understanding, we see
    the relation just below "ODU (ODUflex)"!

    Again, correct.

    I have problems of view.

    No, the figure is not clear.

    - Is ODTU2.3 payload exactly similar to this ODUflex(GFP)?

    I see that the nominal bandwidth of ODTU2.ts for example is the TS
    bandwidth in OPU2. The numeric value in table 7-7 is rounded.

    On the other hand the value of nominal bandwidth of ODU2.ts is exact,
    not rounded, a little bit lower than ODTU2.ts.

    Although it is not mentioned in the table, or note, this
    value is also rounded.

    It is mentioned that this exact value is to easy the clock
    generation. Have you pleased a word for that.

    I do not understand how this would make clock generation easier.
    The GFP mapping automatically adjusts any clock difference.

    Cordialement, Huub.


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  • From Michelot@21:1/5 to All on Sun Feb 21 09:50:11 2016
    Bonsoir Huub,

    Many, many thanks.
    Cordialement,
    Michelot

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