What EtherChannel mode does not send or receive any negotiation frames?

The EtherChannel mode that does not send or receive any negotiation frames is the mode referred to as "On." In this mode, the interfaces are simply bundled together to create a single logical link without any protocol negotiation. This means that the interfaces will form an EtherChannel simply based on configuration, without the need for any communication between them to establish that channel.

By using the "On" mode, you can effectively set up an EtherChannel where the participating interfaces directly channel without relying on protocols such as LACP (Link Aggregation Control Protocol) or PAgP (Port Aggregation Protocol). This can be beneficial in scenarios where strict configuration control is needed, and where simplicity or compatibility with other network devices is paramount.

Other modes, such as Automatic, Desirable, and Passive, involve varying degrees of negotiation and dynamic configuration. These modes are designed to facilitate automatic channel formation through negotiation and protocol, which is why they are not applicable when considering a mode that does not engage in sending negotiation frames.