In classless inter-domain routing (CIDR), what is the prefix notation for a network with subnet mask 255.255.248.0?
255.255.248.0 in binary is: 11111111.11111111.11111000.00000000. Counting the consecutive 1s: 8 + 8 + 5 = 21 bits (/21).
How many total subnets of size /28 can be carved out of a single /24 network block?
Subnetting a /24 into /28 requires borrowing 28 - 24 = 4 bits for subnetting. The total number of subnets created is 2^4 = 16 subnets.
Which field in the TCP header is used by the receiver to inform the sender about the amount of buffer space available for incoming data?
TCP flow control uses the advertised receive window to tell the sender how much additional data the receiver can accept. Therefore A and B describe the receive-window mechanism.
What is the maximum payload data size that can be carried in a standard standard IEEE 802.3 Ethernet frame without jumbo frames?
The Maximum Transmission Unit (MTU) for standard Ethernet payload is 1500 bytes (resulting in a 1518-byte maximum frame including 18 bytes of MAC header and FCS).
Which layer of the OSI model converts bit streams received from physical transmission media into formatted frames?
The Data Link layer packages raw bits from the Physical layer into logical structures called frames using start/end delimiters.