2.1-4 TCP service. When an application uses a TCP socket, what transport services are provided to the application by TCP? Check all that apply. Select one or more: a. Real-time delivery. The service will guarantee that data will be delivered to the receiver within a specified time bound. b. Best effort service. The service will make a best effort to deliver data to the destination but makes no guarantees that any particular segment of data will actually get there. c. Loss-free data transfer. The service will reliably transfer all data to the receiver, recovering from packets dropped in the network due to router buffer overflow. d. Congestion control. The service will control senders so that the senders do not collectively send more data than links in the network can handle. e. Throughput guarantee. The socket can be configured to provide a minimum throughput guarantee between sender and receiver. f. Flow Control. The provided service will ensure that the sender does not send so fast as to overflow receiver buffers. 2.4-8 The DNS authoritative name server. What is the role of an authoritative name server in the DNS? (Check all that apply) Select one or more: a. It provides the definitive answer to the query with respect to a name in the authoritative name server's domain. b. It is a local (to the querying host) server that caches name-to-IP address translation pairs, so it can answer authoritatively and can do so quickly. c. It provides the IP address of the DNS server that can provide the definitive answer to the query. d. It provides a list of TLD servers that can be queried to find the IP address of the DNS server that can provide the definitive answer to this query