Frame Decoding
Protocols recognized by the Frame Decoder
The ability to correctly pre-parse and recognize the most common Ethernet-based protocols is a distinct advantage for most network applications, and is central to many of the advanced Frame Processing and Content Processing features supported by Napatech Network Adapters.
The Frame Decoder does not alter the frames or rearrange the sequence of frames, but extracts the information for use in filters, slicing, multi-CPU buffers etc., and supplies it to the user application in the Packet Descriptors.
Frame types recognized by the Frame Decoder
The depth of the VLAN encapsulation is 3 levels, and the depth of the MPLS encapsulation is up to 7 levels.
The figure to the right illustrates a few examples of different types of frames recognized by the Frame Decoder.
The Frame Decoder is an especially powerful feature in networks with VLAN and MPLS encapsulation and/or in networks that use IP and TCP options. Having the Frame Decoder on the Napatech Network Adapter traverse the packet headers in such scenarios saves a substantial amount of host processing that would otherwise be done by the user application.
Frame decoding of Ethernet frames and encapsulated protocols including common options
