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Extended AttributesRADEXT - IETF 79Alan DeKokFreeRADIUSAvi LiorBridgewaterRequirementsMore RADIUS Attribute Types256 is too limitedStandard support for long attributes> 253 octetsBetter groupingRFC 2868 tags are inadequateRADEXT - IETF 79Un-RequirementsSystems which were discussed and rejectedtoo complextoo limitedwhich cant be applied to existing RFCsRADEXT - IETF 79Current AttributesType

1 octetLength

1 octetValue

1..253 octetsRADEXT - IETF 79Extended AttributesType

1 octetLength

1 octetExt-Type

1 octetValue

1..252 octetsRADEXT - IETF 79Thats pretty much it.Steal one octet of value for extended typesAllocate 4 attributes of this format241, 242, 243, 244Solves the need more attributes problemAllows for ~1K new attributesRADEXT - IETF 79NamingWe need to name the new attributes types.Use OID style dotted number241.{1-255}241.1 This-Is-A-New-attrVersus1 User-NameNaming applies only for the IANA registryRADEXT - IETF 79GroupingBetter grouping by defining a TLV data typeAlready in WiMAX, 3GPP2, and other SDOs / vendors.RADEXT - IETF 79TLV Data TypeTLV-Type

1 octetTLV-Length

1 octetValue

1..253 octetsRADEXT - IETF 79TLV in Ext-AttributeType

1 octetLength

1 octet = 9Ext-Type

1 octetTLV-Type

1 octetTLV-Length

1 octet = 6Value

4 octetsRADEXT - IETF 79TLVs in Ext-AttributeType

1 octetLength

1 octet = 29Ext-Type

1 octetTLV-Type

1 octetTLV-Length

1 octet = 6Value

4 octetsTLV-Type

1 octetTLV-Length

1 octet = 20Value

18 octetsRADEXT - IETF 79TLV PropertiesCan carry any existing or future data typeIncluding TLVs.Multiple TLVs can be carried in one Ext-AttrNested or concatenated Nesting is limited only by TLV-Length field253 / 3 =~ 80Practicalities show a depth of 5 is sufficientRADEXT - IETF 79TLV NamingLeverage the same dotted number notation!241.1.2RADIUS Attr 241, of type ext-attrExtended Attr 1, data type tlvTLV 2, data type integerAllows for ~250 fields in a structExtends type space past 1K attributesRADEXT - IETF 79Long AttributesLeverage the Ext-Type formatAllocate 2 attributes of this type245, 246Add another field: flagsStandard way to say more than 253 octets of dataRADEXT - IETF 79Long Ext AttributesType

1 octetLength

1 octetExt-Type

1 octetFlags

1 octetValue

1..251 octetsRADEXT - IETF 79Flags1 bit of C for ContinuationSame meaning as existing ext-attrs / WiMAX7 bits of reservedWe have no idea what to do with theseIts likely that these will never be usedRADEXT - IETF 79Additional notes24{1-6}.26 are VSAsAllows for many more VSAs24{1-6}.{241-255} are reservedNo experimental or implementation-specificThey have not been usefulDetailed instructions for IANA are includedRADEXT - IETF 79MotivationRADEXT discussions have been longWe need a solution soon (i.e. within 2-3 years)All other solutions are more complexAttribute audit shows the needs to be simpleRADEXT - IETF 79Attribute AuditCountData Type2257 integer1762 text273 IPv4 Address235 string96 other data types35 IPv6 Address18 date4 Interface Id3 IPv6 Prefix4683 TotalPublic dictionaries~100 vendors55% or more are short ( 1K of new attribute spaceWith TLVs, potentially many 1000sGrouping via TLVsProven to work in SDO VSAsStandard way to have long attrsNo more ad hoc methodRADEXT - IETF 79Questions?RADEXT - IETF 79