Although the description is empty, the object name and enumeration values indicate this selects which in-band management channel, the SDH DCCr regenerator-section overhead, DCCm multiplex-section overhead, or a defined user channel, carries SNMP management traffic to this radio over the same fiber path as live traffic, rather than requiring a separate out-of-band network. Choosing an overhead channel that's already claimed by another network element for a different purpose, or one incompatible with the neighboring node's configuration, would break in-band management connectivity to this radio entirely. A network designer standardizing in-band management across a ring of Ceragon radios would set this consistently to, say, dccr(2) on every node so all units communicate over the same overhead channel.