In Figure $1,$ all frames generated at node A are sent to node C through node B$.$

$$ RAB $=1$ Mbps

$$ RBC $=$ R

$$ Prop. Delay $=5/$ for both lines

$$ There are full$-$duplex lines between the nodes

$$ All data frames are $10,000$ bits long

$$ The size of the Ack packets is assumed negligible $(0)$

$$ A $->$ B: sliding$-$window, size $=$ N

$$ B $->$ C: stop$-$and$-$wai