31. A call-processing arrangement for use in a telecommunications system having a plurality of endpoints and having a network numbering plan for addressing the endpoints, wherein callers supply sequences of symbols to specify treatment that is to be given to calls, each sequence comprising at least one symbol string that is defined for the network numbering plan, comprising: defining means for defining the network numbering plan, the plan comprising a plurality of types of symbol strings, the symbol strings of individual types having variable lengths in terms of numbers of symbols that make up individual symbol strings of the individual type, the individual symbol strings each comprising alphabetic symbols or numeric symbols within a predefined digital alphabet and said string being a member either of a natural human language or of a proper name so that said symbol string has a logical meaning outside of the network numbering plan, and addresses of the endpoints of the system within the network numbering plan each comprising at least one symbol string of at least one of the types and addresses of at least some of the endpoints of the system within the network numbering plan each comprising a plurality of symbol strings of a plurality of the types; identifying means cooperative with the defining means and responsive to receipt of a symbol sequence including a plurality of symbol strings of a plurality of the types, the included symbol strings appearing in the symbol sequence in any order, for using the defining means' definition of the network numbering plan to identify symbol strings of the network numbering plan that are included in the received symbol sequence irrespective of their order in the received symbol sequence; and connecting means responsive to the identifying means, for effecting establishment of a connection to an endpoint of the system having an address within the network numbering plan formed by the identified included symbol strings, irrespective of the order of the identified included symbol strings in the received symbol sequence.
32. The arrangement of claim 31 wherein: the defining means comprise means for storing definitions of individual strings of the network numbering plan, each definition including an identification of the string type of the defined string.