Transition Networks C4110-4848, Install Manual

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Transition Networks S4110 Install Guide
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Optical Transport Network (OTN)
The Optical Transport Hierarchy (OTH) is a new transport technology for the Optical Transport Network
(OTN) developed by the ITU. OTH is based on the network architecture defined in ITU G.872
"Architecture for the Optical Transport Network (OTN)".
G.872 defines an architecture that is composed of the Optical Channel (OCh), Optical Multiplex Section
(OMS) and Optical Transmission Section (OTS). G.872then describes the functionality that needed to
make OTN work.
Compared to SONET/SDH, using OTN offers advantages (stronger Forward Error Correction, more levels
of TCM, transparent transport of Client signals, switching scalability) and disadvantages (requires new
hardware and management system).
OTU Type OTU Bit Rate (Nominal)
OTU1 255/238 x 2 488 320 kbit/s
OTU2 255/237 x 9 953 280 kbit/s
OTU3 255/236 x 39 813 120 kbit/s
The OTU bit rate tolerance is ±20 ppm for OTU1, OTU2, and OTU3. The nominal OTUk rates are
approximately 2 666 057.143 kbit/s (OTU1), 10 709 225.316 kbit/s (OTU2) and 43 018 413.559 kbit/s
(OTU3).
See http://www.itu.int/rec/T-REC-G.709/ for more information.
Fibre Channel (FC)
FC (Fibre Channel) is a high-speed network technology (common rates of 2-, 4-, 8- and 16-Gbps) often
used to connect computer data storage. Fibre Channel is standardized in the T11 Technical Committee of
INCITS (the International Committee for Information Technology Standards) an ANSI standards
committee.
Note : When FC technology was developed, it supported only optical cabling (fiber). Copper cable support
was later added, so the development committee kept the same name but changed to the British spelling
'fibre' for the standard. The American English spelling 'fiber' refers only to optical cabling, so a network
using 'fibre' can be implemented either with copper or optical cabling.
The FC protocol has a range of speeds based on a various underlying transport media. Native FC speed
variants include:
Media Line-rate (GBps) Throughput (full duplex; Mbps)* Availability
1GFC 1.0625 200 1997
2GFC 2.125 400 2001
4GFC 4.25 800 2004
8GFC 8.5 1,600 2005
10GFC 10.52 2,550 2008
Fibre Channel does not follow OSI Layer modeling, but is similarly split into five layers (FC0 - FC4):
FC4 : Protocol-mapping layer, in which application protocols, such as SCSI or IP, are encapsulated into a
PDU for delivery to FC2.
FC3 : Common services layer, a thin layer that could eventually implement functions like encryption or
RAID redundancy algorithms.