The Network Layer: Data Plane

What is the primary distinction between the network-layer functions of forwarding and routing?

What is the primary role of a router's forwarding table?

In the context of router architecture, which component connects the router's input ports to its output ports?

What does the 'longest prefix matching rule' dictate a router should do when a destination address matches multiple entries in its forwarding table?

What is head-of-the-line (HOL) blocking in an input-queued switch?

According to the 'rule of thumb' for buffer sizing mentioned in the text, how much buffering should a 10-Gbps link with an average round-trip time of 250 msec have?

In the context of IPv4 datagrams, what is the total size of the header in bytes, assuming no options are used?

What is the purpose of the Time-to-Live (TTL) field in the IPv4 header?

In IP terms, what constitutes a subnet?

What is the four-step process for a host to obtain an IP address using DHCP?

What source IP address and destination IP address does a client use in its initial DHCP discover message?

How does a NAT-enabled router allow multiple devices on a private network to communicate with the wider Internet using a single public IP address?

What is one of the primary motivations for the development of IPv6?

Which IPv4 header field was removed in the standard IPv6 header to speed up processing?

What is the mechanism of tunneling in the context of transitioning from IPv4 to IPv6?

In the OpenFlow 1.0 specification, which of the following is an example of a field that can be matched in a flow table entry?

What is the primary function of a middlebox in a network?

What is the 'IP hourglass' model meant to illustrate about the Internet's architecture?

What does the 'end-to-end argument' suggest about where to place functionality in a network?

Which of the following services is NOT guaranteed by the Internet's 'best-effort' service model?

Which type of switching fabric is described as 'non-blocking', meaning a packet will not be blocked from reaching an output port as long as no other packet is currently being forwarded to that same output port?

Under what condition can packet loss occur at a router's output ports, even if the switching fabric is N times faster than the line speed?

Which packet scheduling discipline ensures that packets depart in the exact same order in which they arrived?

What is the primary purpose of address aggregation (or route summarization)?

What is the 32-bit binary equivalent of the IP address 223.1.3.27?

An application generates chunks of 40 bytes of data. Each chunk is encapsulated in a TCP segment with a 20-byte header and then in an IP datagram with a 20-byte header. What percentage of each datagram is application data?

In OpenFlow generalized forwarding, what does a flow table entry with no specified action indicate?

What is Network Function Virtualization (NFV)?

How many bits long is an IPv6 address?

What is the size of the fixed-length header in an IPv6 datagram?

In weighted fair queuing (WFQ), if class 1 has a weight of 3 and class 2 has a weight of 1, and both classes have packets to send, what fraction of service is class 1 guaranteed to receive?

What does a NAT-enabled router do when it receives a datagram from a host on its private network destined for the public Internet?

What is the protocol number used in an IPv4 header to indicate that the payload is a TCP segment?

How does an SDN controller typically communicate with the data plane switches it manages?

When a large IP datagram is broken into several smaller datagrams through IP fragmentation, where are they reassembled?

What is the maximum theoretical size of an IPv4 datagram in bytes, based on the 'datagram length' field?

If a router's switching fabric transfer rate is N times faster than its line rate R_line, what is the expected level of input port queuing?

Which router component is typically implemented in software and operates on a millisecond or second timescale?

Which organization has the ultimate authority for managing the IP address space and allocating address blocks to regional registries?

In the context of a NAT-enabled router, what is a 'realm with private addresses'?

What is a 'firewall' primarily designed to do?

How does an IPv6 router handle a datagram that is too large to be forwarded over an outgoing link?

In the OpenFlow match-plus-action paradigm, which action involves rewriting values in packet header fields?

What is the key difference between a link-layer switch and a router?

Why must the IP header checksum be recomputed at each router for IPv4?

In a traditional router, which component computes the forwarding table by executing routing protocols?

What is bufferbloat?

What does a slash notation like '/24' in an IP address (e.g., 223.1.1.0/24) indicate?

What is the key functional difference between destination-based forwarding and generalized forwarding?

Under a non-preemptive priority queuing discipline, what happens if a high-priority packet arrives while a low-priority packet is already in transmission?