Explanation/Reference: Explanation: The LACP is Link Aggregation Control Protocol. LACP is an open protocol, published under the 802.3ad. The modes of LACP are active, passive or on. The side configured as “passive” will waiting the other side that should an Active for the Etherchannel to be established. PAgP is Port-Aggregation Protocol. It is Cisco proprietary protocol. The mode are On, Desirable or Auto. Desirable – Auto will establish an EtherChannel. An example of how to configure an Etherchannel: SwitchFormula1>enable SwitchFormula1#configure terminal SwitchFormula1(config)# interface range f0/5 -14 SwitchFormula1(config-if-range)# channel-group 13 mode ? active Enable LACP unconditionally auto Enable PAgP only if a PAgP device is detected desirable Enable PAgP unconditionally on Enable Etherchannel only passive Enable LACP only if a LACP device is detected