# Revision history [back]

Values in the range 147 through 162 are reserved for private use; if you have some link-layer header type that you want to use within your organization, with the capture files using that link-layer header type not ever be sent outside your organization, you can use one or more these values. No libpcap release will use these for any purpose, nor will any tcpdump release use them, either.


LINKTYPE_USER0-LINKTYPE-USER15  147-162 DLT_USER0-DLT_USER15    Reserved for private use; see above.


There is some background info in this ASK question

Values in the range 147 through 162 are reserved for private use; if you have some link-layer header type that you want to use within your organization, with the capture files using that link-layer header type not ever be sent outside your organization, you can use one or more these values. No libpcap release will use these for any purpose, nor will any tcpdump release use them, either.

LINKTYPE_USER0-LINKTYPE-USER15  147-162 DLT_USER0-DLT_USER15    Reserved for private use; see above.