rfc2622.txt

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      origin: AS2

                             Figure 8:  Route Objects




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RFC 2622                          RPSL                         June 1999


5 Set Classes

   To specify policies, it is often useful to define sets of objects.
   For this purpose we define as-set, route-set, rtr-set, filter-set,
   and peering-set classes.  These classes define a named set.  The
   members of these sets can be specified either directly by listing
   them in the sets' definition, or indirectly by having member objects
   refer to the sets' names, or a combination of both methods.

   A set's name is an rpsl word with the following restrictions: All
   as-set names start with prefix "as-".  All route-set names start with
   prefix "rs-".  All rtr-set names start with prefix "rtrs-".  All
   filter-set names start with prefix "fltr-".  All peering-set names
   start with prefix "prng-".  For example, as-foo is a valid as-set
   name.

   Set names can also be hierarchical.  A hierarchical set name is a
   sequence of set names and AS numbers separated by colons ":".  At
   least one component of such a name must be an actual set name (i.e.
   start with one of the prefixes above).  All the set name components
   of an hierarchical name has to be of the same type.  For example, the
   following names are valid: AS1:AS-CUSTOMERS, AS1:RS-EXPORT:AS2, RS-
   EXCEPTIONS:RS-BOGUS.

   The purpose of an hierarchical set name is to partition the set name
   space so that the maintainers of the set X1 controls the whole set
   name space underneath, i.e. X1:...:Xn-1.  Thus, a set object with
   name X1:...:Xn-1:Xn can only be created by the maintainer of the
   object with name X1:...:Xn-1.  That is, only the maintainer of AS1
   can create a set with name AS1:AS-FOO; and only the maintainer of
   AS1:AS-FOO can create a set with name AS1:AS-FOO:AS-BAR. Please see
   RPS Security Document [20] for details.



















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RFC 2622                          RPSL                         June 1999


5.1 as-set Class

   The attributes of the as-set class are shown in Figure 9.  The as-set
   attribute defines the name of the set.  It is an RPSL name that
   starts with "as-".  The members attribute lists the members of the
   set.  The members attribute is a list of AS numbers, or other as-set
   names.

      Attribute    Value                    Type
      as-set       <object-name>            mandatory, single-valued,
                                            class key
      members      list of <as-numbers> or  optional, multi-valued
                   <as-set-names>
      mbrs-by-ref  list of <mntner-names>   optional, multi-valued


                     Figure 9:  as-set Class Attributes

   Figure 10 presents two as-set objects.  The set as-foo contains two
   ASes, namely AS1 and AS2.  The set as-bar contains the members of the
   set as-foo and AS3, that is it contains AS1, AS2, AS3.  The set as-
   empty contains no members.

 as-set: as-foo           as-set: as-bar                as-set: as-empty
 members: AS1, AS2        members: AS3, as-foo


                        Figure 10:  as-set objects.

   The mbrs-by-ref attribute is a list of maintainer names or the
   keyword ANY.  If this attribute is used, the AS set also includes
   ASes whose aut-num objects are registered by one of these maintainers
   and whose member-of attribute refers to the name of this AS set.  If
   the value of a mbrs-by-ref attribute is ANY, any AS object referring
   to the AS set is a member of the set.  If the mbrs-by-ref attribute
   is missing, only the ASes listed in the members attribute are members
   of the set.

    as-set: as-foo
    members: AS1, AS2
    mbrs-by-ref: MNTR-ME

    aut-num: AS3                          aut-num: AS4
    member-of: as-foo                     member-of: as-foo
    mnt-by: MNTR-ME                       mnt-by: MNTR-OTHER


                           Figure 11:  as-set objects.



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   Figure 11 presents an example as-set object that uses the mbrs-by-ref
   attribute.  The set as-foo contains AS1, AS2 and AS3.  AS4 is not a
   member of the set as-foo even though the aut-num object references
   as-foo.  This is because MNTR-OTHER is not listed in the as-foo's
   mbrs-by-ref attribute.

5.2 route-set Class

   The attributes of the route-set class are shown in Figure 12.  The
   route-set attribute defines the name of the set.  It is an RPSL name
   that starts with "rs-".  The members attribute lists the members of
   the set.  The members attribute is a list of address prefixes or
   other route-set names.  Note that, the route-set class is a set of
   route prefixes, not of RPSL route objects.

 Attribute    Value                              Type
 route-set    <object-name>                      mandatory,
                                                 single-valued,
                                                 class key
 members      list of <address-prefix-range> or  optional, multi-valued
              <route-set-name> or
              <route-set-name><range-operator>
 mbrs-by-ref  list of <mntner-names>             optional, multi-valued


                   Figure 12:  route-set Class Attributes

   Figure 13 presents some example route-set objects.  The set rs-foo
   contains two address prefixes, namely 128.9.0.0/16 and 128.9.0.0/24.
   The set rs-bar contains the members of the set rs-foo and the address
   prefix 128.7.0.0/16.

   An address prefix or a route-set name in a members attribute can be
   optionally followed by a range operator.  For example, the following
   set:

   route-set: rs-foo
   members: 128.9.0.0/16, 128.9.0.0/24

   route-set: rs-bar
   members: 128.7.0.0/16, rs-foo


                       Figure 13:  route-set Objects







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   route-set: rs-bar
   members: 5.0.0.0/8^+, 30.0.0.0/8^24-32, rs-foo^+

   contains all the more specifics of 5.0.0.0/8 including 5.0.0.0/8, all
   the more specifics of 30.0.0.0/8 which are of length 24 to 32 such as
   30.9.9.96/28, and all the more specifics of address prefixes in route
   set rs-foo.

   The mbrs-by-ref attribute is a list of maintainer names or the
   keyword ANY.  If this attribute is used, the route set also includes
   address prefixes whose route objects are registered by one of these
   maintainers and whose member-of attribute refers to the name of this
   route set.  If the value of a mbrs-by-ref attribute is ANY, any route
   object referring to the route set name is a member.  If the mbrs-by-
   ref attribute is missing, only the address prefixes listed in the
   members attribute are members of the set.


   route-set: rs-foo
   mbrs-by-ref: MNTR-ME, MNTR-YOU

   route-set: rs-bar
   members: 128.7.0.0/16
   mbrs-by-ref: MNTR-YOU

   route: 128.9.0.0/16
   origin: AS1
   member-of: rs-foo
   mnt-by: MNTR-ME

   route: 128.8.0.0/16
   origin: AS2
   member-of: rs-foo, rs-bar
   mnt-by: MNTR-YOU


                       Figure 14:  route-set objects.

   Figure 14 presents example route-set objects that use the mbrs-by-ref
   attribute.  The set rs-foo contains two address prefixes, namely
   128.8.0.0/16 and 128.9.0.0/16 since the route objects for
   128.8.0.0/16 and 128.9.0.0/16 refer to the set name rs-foo in their
   member-of attribute.  The set rs-bar contains the address prefixes
   128.7.0.0/16 and 128.8.0.0/16.  The route 128.7.0.0/16 is explicitly
   listed in the members attribute of rs-bar, and the route object for
   128.8.0.0/16 refer to the set name rs-bar in its member-of attribute.





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   Note that, if an address prefix is listed in a members attribute of a
   route set, it is a member of that route set.  The route object
   corresponding to this address prefix does not need to contain a
   member-of attribute referring to this set name.  The member-of
   attribute of the route class is an additional mechanism for
   specifying the members indirectly.

5.3 Predefined Set Objects

   In a context that expects a route set (e.g.  members attribute of the
   route-set class), an AS number ASx defines the set of routes that are
   originated by ASx; and an as-set AS-X defines the set of routes that
   are originated by the ASes in AS-X. A route p is said to be
   originated by ASx if there is a route object for p with ASx as the
   value of the origin attribute.  For example, in Figure 15, the route
   set rs-special contains 128.9.0.0/16, routes of AS1 and AS2, and
   routes of the ASes in AS set AS-FOO.

   route-set: rs-special
   members: 128.9.0.0/16, AS1, AS2, AS-FOO


          Figure 15:  Use of AS numbers and AS sets in route sets.

   The set rs-any contains all routes registered in IRR. The set as-any
   contains all ASes registered in IRR.

5.4 Filters and filter-set Class

   The attributes of the filter-set class are shown in Figure 16.  A
   filter-set object defines a set of routes that are matched by its
   filter.  The filter-set attribute defines the name of the filter.  It
   is an RPSL name that starts with "fltr-".

       Attribute   Value         Type
       filter-set  <object-name> mandatory, single-valued, class key
       filter      <filter>      mandatory, single-valued

                    Figure 16:  filter Class Attributes

      filter-set: fltr-foo
      filter: { 5.0.0.0/8, 6.0.0.0/8 }

      filter-set: fltr-bar
      filter: (AS1 or fltr-foo) and <AS2>

                      Figure 17:  filter-set objects.




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RFC 2622                          RPSL                         June 1999


   The filter attribute defines the set's policy filter.  A policy
   filter is a logical expression which when applied to a set of routes
   returns a subset of these routes.  We say that the policy filter
   matches the subset returned.  The policy filter can match routes
   using any BGP path attribute, such as the destination address prefix
   (or NLRI), AS-path, or community attributes.

   The policy filters can be composite by using the operators AND, OR,
   and NOT.  The following policy filters can be used to select a subset
   of routes:

   ANY
      The keyword ANY matches all routes.

   Address-Prefix Set This is an explicit list of address prefixes
      enclosed in braces '{' and '}'.  The policy filter matches the set
      of routes whose destination address-prefix is in the set.  For
      example:

        { 0.0.0.0/0 }
        { 128.9.0.0/16, 128.8.0.0/16, 128.7.128.0/17, 5.0.0.0/8 }
        { }


   An address prefix can be optionally followed by a range operator
   (i.e.

      { 5.0.0.0/8^+, 128.9.0.0/16^-, 30.0.0.0/8^16, 30.0.0.0/8^24-32 }


   contains all the more specifics of 5.0.0.0/8 including 5.0.0.0/8, all
   the more specifics of 128.9.0.0/16 excluding 128.9.0.0/16, all the
   more specifics of 30.0.0.0/8 which are of length 16 such as
   30.9.0.0/16, and all the more specifics of 30.0.0.0/8 which are of
   length 24 to 32 such as 30.9.9.96/28.

   Route Set Name  A route set name matches the set of routes that are
   members of the set.  A route set name may be a name of a route-set
   object, an AS number, or a name of an as-set object (AS numbers and
   as-set names implicitly define route sets; please see Section 5.3).
   For example: