Hi,
Below are my comments on the current PDM MIB text.
Cheers,
- Ira
--
Ira McDonald (Musician / Software Architect)
Chair - Linux Foundation Open Printing WG
Blue Roof Music / High North Inc
PO Box 221 Grand Marais, MI 49839
work: +1-906-494-2434
home: +1-906-494-2697
email: blueroofmusic at gmail.com
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Comments on PDM MIB - by Ira McDonald - 17 October 2007
* Important to use well-formed ASN.1 labels
- Labels should NOT be longer than 31-characters - breaks compilers
- Table should be pdmGroupTable
- Entry should be pdmGroupEntry
- Columnar should be pdmGroupColumnarName
* Enum
- ASN.1 labels for enumerated values MUST start with lowercase alpha
- always reserve (and usually define) other(1) and unknown(2)
- do NOT use zero or negative values - e.g. PostStatus
* String datatypes
- Set by system - PdmLocalizedStringTC (UTF-8)
- Set by client - SnmpAdminString (UTF-8)
- ISO/IANA Keywords - DisplayString (US-ASCII visible only)
- Required string constants - min length zero with conformance stated
- Do NOT use "OCTET STRING" directly for any human-readable string
* Localization
- all human-readable strings MUST be UTF-8 (other charsets illegal)
- Language Tags defined by RFC 4646 (up to 63 characters)
- Ira will propose rewrite of Localization group soon
* Limits
- Integers - Specify explicit min/max value
- Strings - Specify explicit min/max length
* DateTime objects
- Need PdmDateTimeTC - XML format date and time
* Age, Time, Size objects
- Need UNITS clause - and explicit units in Description
* Uptime
- must use TimeTicks as SYNTAX
- note that all SNMP traps MUST bind Uptime, so XML DateTime redundant
* Should use of DISPLAY-HINT clauses, when appropriate
* Index
- Use 32-bit positive range - NOT 16-bit range (deprecated by IETF)
* Counter
- use Counter32 - NOT Integer32
- object label MUST end in "Counter" or "Count" - per IETF guidelines
* Gauge
- use Gauge32 - NOT Integer32
- object label SHOULD end in "Gauge" - per IETF guidelines