The start function required by diameter_transport(3).
The only diameter_tcp-specific argument is the options list.
Options raddr and rport specify the remote address
and port for a connector and not valid for a listener.
Remaining options are any accepted by gen_tcp:connect/3 for
a connector, or gen_tcp:listen/2 for a listener, with the exception
of binary, packet and active.
Also, option port can be specified for a listener to specify the
local listening port, the default being the standardized 3868 if
unspecified.
Note that option ip specifies the local address.
If the service specifies more than one Host-IP-Address and
option ip is unspecified then then the
first of the service's addresses is used as the local address.
The returned local address list has length one.