EXFO FTB/IQS-85100G Packet Blazer for FTB-500/IQS-600 - Manual (Page 396)

Glossary
386 FTB/IQS-85100G
Generic Framing Procedure (GFP)
The GFP generic frame structure is presented in figure below.
GFP Generic Frame Structure
Each GFP frame type consists of three main components: the core header,
the payload header, and the payload information field.
The core and payload headers form the GFP header, whereas the payload
information field represents the customer traffic carrying the data services.
The payload header carries information about the payload type (i.e.,
Ethernet, Fibre Channel, etc.) that it is carrying, while the core header
carries information about the size of the GFP frame itself.
Each header contains a header error correction (HEC) calculation,
allowing for the correction of single errors; that is, any errors that occur in
the core header or in the payload header can potentially be corrected by
the HEC, through the network element. This creates a very robust mapping
scheme, which ensures that GFP frames can get transported across a
network without customer traffic loss.