$($a$)$ How can the LTE core network be interconnected with legacy core networks?

$($b$)$ Whys should this be done?

Describe different options for the backhaul connection of the eNB.

Describe the differences between the tasks for the MME and the tasks of the S$-$

GW$.$

How does a mobile device get access to the PUSCH?

How is mobility controlled in RRC idle state?

How many subcarriers are used for a $10$MHz FDD$-$LTE channel?

What are the differences between ARQ and HARQ?

What is an RB$?$

What is CS$-$fallback?

What is the big disadvantage of Internet$-$based voice services compared to

network operator$-$based voice services?

What is the difference between a cell change order and a handover?

What is the difference between a default and a dedicated bearer?

What is the difference between an S$1$ and an X$2$ handover?

What is the purpose of DRX in RRC connected state?