Technical data

TraverseEdge 2020 Applications and Engineering Guide, Chapter 3: System Applications
Page 3-52 Turin Networks Release 5.0.x
NOTE: Once the virtual concatenation has taken place, each constituent STS-Nc-Xv operates inde-
pendently in the SONET network, and may be individually routed or protection switched.)
NOTE: Constituent STSs in a Virtual Concatenation Group do not have to be contiguous.
The Gigabit Ethernet PLM supports both Virtual concatenation connections and standard SONET
connections as listed in Table 3-20 . Standard SONET connections are not contained in VC
groups. Line rate for Gigabit Ethernet is achieved using STS-3c-7v or STS-1-21v connections.
Table 3-20 Gigabit Ethernet Cross-Connects and VC group types
In the egress direction, the GbE PLM receives multiple STS-Nc-Xv connections. It provides SONET path
termination for each of the STS paths that make up the STS-Nc-Xv connections. For each STS-Nc-Xv con-
nection, the GbE PLM compensates for any differential delay that the transport network has introduced.
The GbE PLM then checks the GFP frames recovered from the STS-Nc-Xv payload. Ethernet frames are
extracted from valid GFP frames, checked for errors, then (if valid), delivered out the egress GbE inter-
face.
The GbE PLM may be inserted in any of the four upper slots (AIDs 1-1, 1-2, 2-1, or 2-2) of the TE-2020
Main Shelf or the OTS2 shelf.
Ethernet Functions
The GbE PLM follows a simple, yet powerful model for Ethernet transport: Under normal operating condi-
tions, all valid Ethernet frames enter the SONET network over one GbE interface and exit the network
over another, pre-defined GbE interface. These frames pass through the network unchanged: the EoS map-
ping does not alter any of the fields of the Ethernet frames. Stated another way, this EoS transport model is
transparent at the Ethernet Media Access Control (MAC) layer.
Nomenclature Contents
STS-1 A single STS-1. No Virtual Concatenation is used. The user should select the STS-1 sig-
nal type not the VC signal type to implement this connection.
STS-3c A single STS-3c. No Virtual Concatenation is used. The user should select the STS-3c
signal type not the VC signal type to implement this connection.
STS-12c A single STS-12c. No Virtual Concatenation is used. The user should select the STS-12c
signal type not the VC signal type to implement this connection.
STS-1-Nv N Virtually concatenated STS-1s using a VC group; N = 1..21
NOTE: An STS-1-1v is a single STS-1 VC group. It is not the same as using a single
STS-1 (H4 SONET overhead byte is different). A user may choose this option if the ini-
tial signal is a single STS-1 but in the future may grow to multiple STS-1s. The VC
group could then be modified.
STS-3c-Nv N Virtually concatenated STS-3cs using a VC group; N = 1..7
NOTE: An STS-3c-1v is a single STS-3c VC group. It is not the same as using a single
STS-3c (H4 SONET overhead byte is different). A user may choose this option if the
initial signal is a single STS-3c but in the future may grow to multiple STS-3cs. The VC
group could then be modified.