Answer
GFI FaxMaker does not require an exact match between the called party number and the MSN list entries in order to accept an incoming call. The range of MSNs allocated to an ISDN installation is always sequential with variations only to the end digits. The called party number reaching GFI FaxMaker takes always the form of:<fixed number><varying number>
It is the trailing digits that differentiate the called party numbers reaching GFI FaxMaker. For this reason GFI FAXmaker treats the MSN list entries as prefixes to the called party number.
Consider a GFI FaxMaker installation with the following called party number range: '3131324' to '3131356'
In this case the '31313' is the number which will always reach GFI FaxMaker for every incoming call whereas the trailing two digits uniquely identify the number dialed at the sending end. Since GFI FaxMaker treats the MSN entries as prefixes to the called party number, MSN entries of 3, 31, 313, 3131 or 31313 will always match the called number. Hence GFI FaxMaker would accept all incoming calls. Using the same reasoning the following table can be derived. Note that the numbers in red, identify the digits considered by GFI FaxMaker when matching an MSN.
| MSN Entry | Accepted Called Party Numbers |
| No Entries | No number accepted |
| 3 | 3000000 to 3999999 |
| 31 | 3100000 to 3199999 |
| 313 | 3130000 to 3139999 |
| 3131 | 3131000 to 3131999 |
| 31313 | 3131300 to 3131399 |
| 313132 | 3141320 to 3131329 |
| 313133 | 3141330 to 3131339 |
| 313134 | 3141340 to 3131349 |
| 313135 | 3141350 to 3131359 |
| 3131324 | 3141324 |
| 3131326 | 3141326 |
| .. | .. |
| .. | .. |
| .. | .. |
| .. | .. |
| 3131354 | 3141354 |
| 3131355 | 3141355 |
| 3131356 | 3141356 |