Link Layer: Setting the Context o Two physically connected devices e Host-router, router-router host-host ● Unit of data: frame M lication M l transport TH M network data link network protoco HnH+I M link link Hi HnHtM physical physical hys link frame adapter card 5: DatLink Layer: Setting the Context  Two physically connected devices:  Host-router, router-router, host-host  Unit of data: frame 5: DataLink Layer 5-3 application transport network link physical network link physical M M M M Ht HnHt Hl HnHt Hl HnHt M frame phys. link data link protocol adapter card