Chapter 11. Dial Plan11-12 ATLAS 550 User Manual 61200305L1-1If the incoming number is ten digits, but with a different area code, it is for-warded to the network as ISDN-National preferred.ISDN-N ATIONALDMS R ESERVEDPREFERREDIgnores the incoming numbering plan and type and substitutes the ISDN/Telephony numbering plan and National number type. Ten digits are sentto the network. Leading ones, if present, are stripped out and the area codeset in global parameters is added if only seven digits are supplied. Thisaction may be required in areas with ten-digit local dialing.ISDN-N ATIONALA S D IALEDSends the digits provided as National number type.S TRIP MSD Write security: 3; Read security: 5Strips a selected quantity (choose from N ONE, 1, 2, and 3) of the Most Signif-icant Digits (MSD) of a dialed number prior to being forwarded out of theport.Example:A network port could be set to accept all calls beginning with 9 (9$), andthen with STRIP MSD set to 1, all digits would be sent toward the networkexcept the leading 9.When SWITCH TYPE is set to 4ESS, many installations require theNational form where possible; this may also be the preferred form in10-digit calling areas.STRIP MSD does not affect C ALL A CCEPT criteria. All of the digits(including the MSDs that are subsequently stripped) are used asaccept criterion.
