This attribute contains the time taken for a packet (cell) of 44 bytes
to be transmitted to the remote LCo and return to this LCo. The
number reported is given in milliseconds to the nearest millisecond.
A value of one millisecond is reported if the time is less than 1
millisecond even though the delay may be less than 1 millisecond
when the LCo is originated and terminated on the same module.