X.25 Framing (NDIS 5.1)
Note NDIS 5. x has been deprecated and is superseded by NDIS 6. x. For new NDIS driver development, see Network Drivers Starting with Windows Vista. For information about porting NDIS 5. x drivers to NDIS 6. x, see Porting NDIS 5.x Drivers to NDIS 6.0.
The following diagram illustrates X.25 framing with protocol field compression turned on and off..png)
Address and Control Field Compression should not be enabled for X.25. If Protocol Field Compression is turned ON, the NLPID should be removed. It is the responsibility of the X.25 driver or hardware to provide for transparency, add any padding, add any FCS, and add any end flag.