The list of character ports offer the service. The
OCTET STRING contains a bitmap, with one bit for
each port, and enough octets for all the ports on
the system. Port numbers are as defined for
charPortIndex in the Character MIB [11].
Corresponding bit numbers start with 1 as the
high-order bit of the first octet. Corresponds
directly to port-list portion of SERVICE PORTS and
the value labeled 'Ports:' in the SERVICE
CHARACTERISTICS display.