Enter the command line using telnet with the admin account.
Here we define a port-forward rule named my-ssh which will redirect the external TCP/59722 port of the router to the internal host 192.168.1.3, TCP/22 port:
DLINK# configure DLINK(cfg)# nat DLINK(cfg-nat)# add portmapping my-ssh DLINK(cfg-nat)# portmapping my-ssh DLINK(cfg-nat-portmap:my-ssh)# extPortList add TCP:59722 DLINK(cfg-nat-portmap:my-ssh)# host 192.168.1.3 DLINK(cfg-nat-portmap:my-ssh)# intPort 22 DLINK(cfg-nat-portmap:my-ssh)# allInterfaces enable DLINK(cfg-nat-portmap:my-ssh)# enable DLINK(cfg-nat-portmap:my-ssh)# show DLINK(cfg-nat-portmap:my-ssh)# config