Next-Gen - Generic Framing Procedure (Gfp) - EXFO FTB-8510B Guia Del Usuario

Glossary

Next-Gen - Generic Framing Procedure (GFP)

Next-Gen - Generic Framing Procedure (GFP)
Generic framing procedure (GFP), defined in ITU recommendation
G.7041/Y.1303, is a framing mechanism to transport packet-based client
signals, such as Ethernet, Fibre Channel, ESCON, FICON, over
fixed-data-rate optical channels. As such, GFP provides a single, flexible
mechanism to map these client signals into SONET/SDH and OTN
networks, as shown in figure below.
Client Signal Mapping over GFP
Prior to the introduction of GFP , several methods had been used to
transport packet services over SONET/SDH networks. The first method was
Asynchronous Transfer Mode (ATM) Adaptation Layer 5 (AAL 5) over
SONET/SDH. ATM is a very efficient switching and multiplexing technology,
whose transfer rates scale with SONET/SDH rates. However, ATM does not
make the most efficient use of bandwidth because the payload data is
separated into groups of 48 bytes, called cells, with an additional 5-byte
header of software overhead. It became immediately apparent that almost
10% of the bandwidth would be lost. In addition, certain types of data
required even more ATM overhead.
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SONET/SDH Application