<!ELEMENT cdrServer (group, radiusServer, billing)><!ATTLIST cdrServer host CDATA #REQUIRED                    port CDATA #REQUIRED><!ELEMENT group EMPTY><!ATTLIST group value CDATA #IMPLIED><!ELEMENT radiusServer EMPTY><!ATTLIST radiusServer host     CDATA  #REQUIRED                       retries  CDATA  #REQUIRED                       secretKey CDATA #REQUIRED><!ELEMENT billing EMPTY><!ATTLIST billing frequency       CDATA #REQUIRED                  dirPath         CDATA #REQUIRED                  lockFile        CDATA #REQUIRED                  dataFile        CDATA #REQUIRED                  unsentExtension CDATA #REQUIRED                  rolloverSize    CDATA #REQUIRED                  rolloverPeriod  CDATA #REQUIRED                  billForRingtime ( true | false ) #REQUIRED>