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DOCS QOS MIB: 1 Open Issue 1 remaining OPEN ISSUE The DOCS QOS MIB draft-ietf-ipcdn-qos-mib-09 contains two read-create TOS related MIB objects docsQosServiceClassTosAndMask docsQosServiceClassTosOrMask (I-D references the obsolete IPv4 TOS Octet as defined in RFC 791) These objects define the “TOS Overwrite” parameters for an upstream service class. They allow the operator to modify individual bits in the IPv4 TOS Octet including ECN bits. Issue: These 2 objects can be SET through SNMP, and their values could change a packet’s ECN bits. DSCPs are not supposed to be “masked” The use of TOS in object names is discouraged, in favor of DSCP PROPOSED RESOLUTION for WG REVIEW Make the 2 TOS objects read-only Allow operator to maintain existing DOCSIS implementations Reference the definition of TOS per RFC 2474 with ECN bits as defined in RFC 3168 Add a new writable object for “DSCP Overwrite” Allow diffserv compliant operation & preserves ECN Use DscpOrAny Textual-Convention from RFC 3289 Values 0..63 = overwrite DSCP with value Value –1 = don’t overwrite Maintains object naming conventions that exist in QoS MIB & DOCSIS RFI Specification while allowing better control of DSCP values |