Internet Direct (Indy) Version 9.0.2 Beta
TIdRSHServer.ForcePortsInRange
This property indicates if the server should disconnect clients that do not connect from the port range (512 - 1023).

property ForcePortsInRange: Boolean;
Description
This property indicates if the server should disconnect clients that do not connect from the port range (512 - 1023). If this property is true, the RSH Server component will automatically disconnect clients that do not do connect to the server from ports in this range. Setting this to False will permit the client to use the RSH server even if they do not connect from this port range.

Usually, this should be set to true to prevent non-administrative users from using the RSH server. Setting this to false should be done with the utmost caution as it will increase the likelihood for abuse. The reason RSH requires clients to connect from ports in the 512-1023 range is because on most multi-user operating systems, this ensures some security as only administrators on those systems could use it. However, "security" is somewhat limited because many single user operating systems will not prevent non-administrator users from using those reserved ports and it is possible for hackers to alter port numbers on packets.