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SubjectRequesting clarification on IPTOS_* values w/regard to RFC-1349
I have a hard time believing that the kernel is wrong
on something so basic, but I cannot reconcile RFC-1349
with include/linux/ip.h

Here is the snippet from RFC-1349, found here:
http://www.cis.ohio-state.edu/cgi-bin/rfc/rfc1349.html

****************************************************************************
3 Specification of the Type of Service Octet

The TOS facility is one of the features of the Type of Service
octet in the IP datagram header. The Type of Service
octet consists of three fields:

0 1 2 3 4 5 6 7
+-----+-----+-----+-----+-----+-----+-----+-----+
| | | |
| PRECEDENCE | TOS | MBZ |
| | | |
+-----+-----+-----+-----+-----+-----+-----+-----+

The first field, labeled "PRECEDENCE" above, is intended to denote the
importance or priority of the datagram. This
field is not discussed in detail in this memo.
****************************************************************************


However, include/linux/ip.h defines the values as if RFC-1349 numbered
the bits backwards. (It appears to me, for example, that the TOS_MASK
should be, in binary: 0111 1000, not 0001 1110 as ip.h shows.)

*************************************************
/* SOL_IP socket options */

#define IPTOS_TOS_MASK 0x1E
#define IPTOS_TOS(tos) ((tos)&IPTOS_TOS_MASK)
#define IPTOS_LOWDELAY 0x10
#define IPTOS_THROUGHPUT 0x08
#define IPTOS_RELIABILITY 0x04
#define IPTOS_MINCOST 0x02
*************************************************


Am I even more confused than normal, or is this really a problem?


Thanks,
Ben


--
Ben Greear <greearb@candelatech.com> <Ben_Greear@excite.com>
President of Candela Technologies Inc http://www.candelatech.com
ScryMUD: http://scry.wanfear.com http://scry.wanfear.com/~greear
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