DateAndTime which we are using for date and time in our Job Monitoring MIB
is not printable characters; its binary (don't be fooled by the display
hint, which is just how to convert the binary to text).
We decided to have two values in our Resource Table (which I'm renaming
to Attribute Table due to some confusion about resources in the e-mail and
since we have agreed to put more than just resources into it):
jmAttributeValueAsInteger
jmAttributeValueAsText
I would suggest that you might also want to add 'textencoding' as well.
For example, you might have UNICODE text or simple ASCII text.
Since Text is represented as OCTET STRING in SNMP, there is no problem
with sending the binary using the same object. However, we might want
to rename the second object to jmAttributeValueAsOctets, so that it
covers the DateAndTime.
Comments?
Tom
WARNING:
By the way, SNMPV2-TC isn't very clear whether the two octet year is
Big Endian or Little Endian, but I suspect that it must be Big Endian,
since SNMP uses ASN.1 which is Big Endian (most significant octet first).
So the year 256 would be represented as 1 in the first octet and 0 in the
second octet, not the other way around.
Be careful, since PCs are Little Endian, so they have to swap the octets.
I believe that there is a general fiat that the Network Standard Order
for multiple octect values is Big Endian.
RFC 1903 SNMPv2-TC is copied as follows:
DateAndTime ::= TEXTUAL-CONVENTION
DISPLAY-HINT "2d-1d-1d,1d:1d:1d.1d,1a1d:1d"
STATUS current
DESCRIPTION
"A date-time specification.
field octets contents range
----- ------ -------- -----
1 1-2 year 0..65536
2 3 month 1..12
3 4 day 1..31
4 5 hour 0..23
5 6 minutes 0..59
6 7 seconds 0..60
(use 60 for leap-second)
7 8 deci-seconds 0..9
8 9 direction from UTC '+' / '-'
9 10 hours from UTC 0..11
10 11 minutes from UTC 0..59
For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be
displayed as:
1992-5-26,13:30:15.0,-4:0
Note that if only local time is known, then timezone
information (fields 8-10) is not present."
SYNTAX OCTET STRING (SIZE (8 | 11))
This is also the standard for representing time in some other ISO standards.
Why not make this the cannonical way to represent time/date values?
Patrick