1) what are the two main functions of a datagram-based network layer? what additional functions does a vc-based network layer have? 2) list and describe the atm network service models. 3) compare and contrast link-state and distance-vector routing algorithms. 4) discuss how a hierarchical organization of the internet has to scale to millions of users. 5) it is necessary that every autonomous system use the same intra-autonomous routing algorithm? why or why not?

the issued Automatic Private IP Addressing (APIPA) address.

Explanation:

Since we are told that the user was able to access the network resources yesterday, and all the network equipment in the user's computer is functioning properly, there is a very high possibility that because the user's computer has been issued an Automatic Private IP Addressing (APIPA) address, it affected his computer's ability to connect to a public network.

This is the case because private network IP addresses are known to prevent inflow and outflow of data onto public networks.