Setting this object to a value as detailed furter on 
(except 0) will initiate a test on the specific port. 
The test/s requested will be set according to the respective
bit. The value of this object will be a sum of (2**n), where n is
the Bit:
  TEST                  BIT                           VALUE
 -----------            ---                                              ------
 reserved                0                                                  1
         PayloadLoop=RLB         1 (=Remote Loopback)       2
 LineLoop=DIG            2 (=Digital)                       4
 OtherLoop               3                                                  8
 InwardLoop=LLB          4 (=Local Loopback)       16
 BERT                    5                                                 32
 LC                      6                         64

 e.g : If the requested value is 20 -> 010100  ->
       Bits 2 & 4 are set -> the requested tests are :
                             LineLoopback=DIG
                             InwardLoopback=LLB
                               
Not all tests combinations are valid.
    For valid test combination, see each product's specification.

The terminology and order of tests (except BERT) is according to 
    the one used for Test Status of DS1 and DS3 standards.

Setting this object to stop (value=0 ; all bits are 0), 
will stop all the user requested tests running on the 
selected port.

When no test is running on the port, the Get value (test status)
    will be 0.

    PayloadLoop=RLB
      The received signal at this interface is looped
      through the device.  Typically the received signal
      is looped back for retransmission after it has
      passed through the device's framing function.

    LineLoop=DIG
      The received signal at this interface does not
      go through the device (minimum penetration) but
      is looped back out.

    OtherLoop
      Loopbacks that are not defined here.

    InwardLoop=LLB
      The sent signal at this interface is looped back
      through the device.

    LC
      This loop is applicable only for HSSI interface, towards the router .