EXFO FTB-1, Руководство пользователя

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Glossary
NetBlazer
593
10G Ethernet Client
10G Ethernet Client
The OTN Overclocked technology provides the capability to transparently
transport 10G base-R Ethernet signals into OPU2 as specified in ITU-T. Two
optical rates are provided:

11.0957 Gbits/s, +/- 100 ppm, designated OTU2e

11.0491 Gbits/s, +/- 100 ppm, designated OTU1e
The OTU2e uses the mapping scheme of CBR10G into OPU2 as defined in
G.709. The client signal, 10GE LAN and the OPU fixed stuff bytes are
accommodated into an OPU-like signal designated OPU2e. This signal is
then wrapped in an ODU2e and then in an OTU2e signal.
The OTU1e uses the mapping scheme of CBR2G5 into OPU1 as defined in
G.709. The client signal, 10GE LAN is accommodated into an OPU-like
signal designated OPU1e (note that the fixed stuff bytes are not left free)
this is why the 10GE signal can be transported at a lower rate than OTU2e.
This signal is then wrapped in an ODU1e and then in an OTU1e signal.
The transparent transport of the 10G base-R means that the full 10G
Ethernet data rate i.e. 10.3125 Gbit/s is transported over OTN. This means
that the following information is transported:

PCS 64B/66B coded information

IPG (inter-frame filler), MAC FCS, Preamble and SFD (start of frame
delimiter) and Ordered Sets (Remote Fault indication)
The OTN clocking is derived from the Ethernet client signal which is +/-
100 ppm, this is outside the clock tolerance allocated by the G.709 standard
which translates in unspecified jitter performance thus limiting the
application to Point to Point data path.