Two switches have been implemented and all interfaces are at the default configuration level. A trunk link must be implemented between two switches with these requirements: - using an industry-standar

`switchport mode dynamic` (presumably dynamic auto) attempts to convert the link to a trunk if the neighboring port is set to trunk or dynamic desirable, but it does not guarantee a trunk nor explicitly set the allowed VLANs as required.

To establish a trunk link that uses an industry-standard protocol (like IEEE 802.1Q) and specifically permits certain VLANs, the interconnecting ports must be explicitly configured with `switchport mode trunk`. This command puts the interface into a permanent trunking mode, and subsequently, `switchport trunk allowed vlan 1-10` would be used to filter the permitted VLANs, fulfilling all requirements.

`switchport mode dynamic desirable` actively attempts to convert the link into a trunk, but it still relies on negotiation and does not explicitly set the trunking mode or the allowed VLANs, which is required for a deterministic and restricted trunk.