Question 1

What field in the basic IPv6 header is used to chain additional headers?

Accepted Answer

The "Next Header" field in the basic IPv6 header specifies the type of the next header, which could be an extension header or the upper-layer protocol header. This mechanism is used to chain additional headers.

Question 2

Because PHB is independent of how individual routers are configured, the end-to-end behavior of traffic is predictable.

Accepted Answer

PHB (Per-Hop Behavior) depends on the configuration of individual routers to ensure the desired treatment of packets, making the end-to-end behavior of traffic dependent on the configuration of each router in the path.

Question 3

Which field specifies the header type of the header immediately following the IPv6 header?

Accepted Answer

The "Next Header" field in the IPv6 header specifies the type of the header immediately following the IPv6 header. This could indicate a TCP, UDP, or another type of header.

Question 4

In IPv6, each extension header is identified by a specific value known as which of the following.

Accepted Answer

The "Next Header" field in an IPv6 packet specifies the type of the next header in the packet, which could be an extension header or the upper-layer header if no more extension headers are present. This mechanism allows for the chaining of extension headers in IPv6 packets.

Question 5

The value in which of the following fields will decrement by one each time it is forwarded by a network node, and the IPv6 packet is discarded if the value in this field reaches 0?

Accepted Answer

The correct field is "Hop Limit" in IPv6, which decrements by one at each node the packet passes through, and the packet is discarded if this value reaches 0. This mechanism prevents packets from looping indefinitely.

Question 6

Jumbograms use which of the following extension headers to add an alternate Packet Length field of 32 bytes?

Accepted Answer

Jumbograms use the Hop-by-Hop Options extension header to add an alternate Packet Length field of 32 bytes, allowing for the transmission of IPv6 packets larger than the standard maximum packet size.

Question 7

The ____ extension header provides a method for extending the IPv6 header to support options for packet handling and preferences.

Accepted Answer

The answer of The ____ extension header provides a method...

Question 8

Which extension header is designed to carry information that affects routers along a path?

Accepted Answer

The Hop-by-Hop Options header is designed to carry information that needs to be examined by all devices (routers and the destination) along the packet's path in an IPv6 network. This can include options for routing, traffic management, and other purposes that affect how the packet is processed at each hop.

Question 9

Unlike IPv4 packets, IPv6 packets ensure that data or application information is successfully transported from a source to a destination node on a network.

Accepted Answer

IPv6, like IPv4, does not inherently ensure successful data transport; it primarily provides addressing and routing. Reliability is typically managed by transport layer protocols like TCP, not by IP protocols themselves.

Question 10

Which field defines the length of the IP header and any valid data (although it does not include any data link padding)?

Accepted Answer

The "Total Length" field in the IP header specifies the length of the entire IP packet, including the header and data, but it does not account for any padding added at the data link layer.

Question 11

How many possible fields can be contained in an IPv4 header?

Accepted Answer

An IPv4 header contains 14 fields. These include fields such as version, header length, total length, protocol, source IP address, destination IP address, and others, which are essential for the routing and delivery of data packets across IP networks.

Question 12

Which of the following is a special marker with which traffic can be prioritized by an end device or boundary device and queued and forwarded according to this value?

Accepted Answer

DSCP (Differentiated Services Code Point) is used in IP headers to enable different levels of service to be assigned to network traffic. This is how traffic can be prioritized and managed by devices along the path.

Question 13

IPv6 jumbograms are specified as a proposed standard in which of the following RFCs?

Accepted Answer

IPv6 jumbograms, which allow packets larger than 65,535 bytes, are specified in RFC 2675. This was proposed to accommodate the need for larger packet sizes in certain applications and networks.

Question 14

The Type of Service field actually has two components: Precedence and which of the following?

Accepted Answer

The Type of Service (ToS) field in the Internet Protocol (IP) header is used to indicate the quality of service desired for a particular packet. It includes two components: Precedence, which indicates the priority of the packet, and Type of Service itself, which specifies how an upper-layer protocol would like a current datagram to be handled, and assigns datagrams various levels of importance.

Question 15

Though defined in terms of seconds, a TTL value is implemented as a number of hops that a packet can travel before being discarded by a router.

Accepted Answer

The TTL (Time to Live) value is indeed defined in seconds, but it is implemented as a hop count, which decreases by one each time the packet passes through a router.

Question 16

The fixed IPv6 header of an IPv6 packet is made up of how many octets?

Accepted Answer

The fixed IPv6 header is made up of 40 octets.

Question 17

In IPv6, which extension header should be used to encrypt data?

Accepted Answer

The Encapsulating Security Payload (ESP) extension header in IPv6 is used to provide confidentiality, data origin authentication, connectionless integrity, an anti-replay service (a form of partial sequence integrity), and limited traffic flow confidentiality.

Question 18

When a packet is sent between two ECN-capable routers, the packet is usually marked ECT(0) or ECT(10) for ECN Capable Transport.
Indicate the answer choice that best completes the statement or answers the question.

Accepted Answer

Packets are marked ECT(0) or ECT(1) for ECN Capable Transport, not ECT(10).

Question 19

The Internet Protocol (IP) primarily works to transmit and deliver data between devices on internetworks.

Accepted Answer

The Internet Protocol (IP) is designed to transmit data packets between devices across different networks, ensuring that data reaches its intended destination.

Question 20

Which field in an IPv6 packet is used by source network hosts and forwarding routers to distinguished classes or priorities?

Accepted Answer

The Traffic Class field in an IPv6 packet is used to identify the class or priority of the packet. This allows for differentiation of the packet for quality of service (QoS) purposes, enabling the network to provide different levels of service based on the class or priority indicated.

Quiz 3: Basic Ip Packet Structures: Headers and Payloads