Identifies the virtual channel identifier of the Optical Concentration Device (OCD) port.
USAGE: This field is conditional.
NOTE 1: Required when the XOCD field is populated.
DATA CHARACTERISTICS: 11 alpha/numeric characters (including decimal points separating each entry)
EXAMPLES: 3 6 A . 3 2 Z
1 2 3 A . 2 3 4 Z