Re: Address and Control Field Compression in RFC 1661
James Carlson <[email protected]>
| Newsgroups | gmane.ietf.pppext |
|---|---|
| Message-ID | <[email protected]> |
Couch, William Garrant, JR (Garry) writes: > PPPEXTers, > > I'm hoping that one or more of you can shed some light on section 6.6, Address and Control Field Compression, in RFC 1661. Is this intended to refer to a specific compression method, a general compression method, or just to the dropping of prefixed zero octets (as in the previous section, 6.5, on Protocol Field Compression)? It refers only to the _removal_ of the HDLC Address and Control fields from the frames. It has nothing to do with data compression or zero octets. The Address and Control field values are (assuming you're not using Frame Relay, RFC 1663, or some other HDLC-based scheme that relies on those fields) a fixed hex FF 03 on each packet. Since "FF 03" can never be a legal protocol number, it's safe to just discard those two bytes -- omit them entirely from the datagram sent on the wire. This option negotiates that feature. -- James Carlson, KISS Network <[email protected]> Sun Microsystems / 1 Network Drive 71.232W Vox +1 781 442 2084 MS UBUR02-212 / Burlington MA 01803-2757 42.496N Fax +1 781 442 1677 _______________________________________________ Pppext mailing list [email protected] https://www1.ietf.org/mailman/listinfo/pppext