Ch 4: Network Protocols and Routing

Question 1

What is NOT one of the three characteristics of TCP in its role as a reliable delivery protocol?

Answer 1

Framing

Question 2

What field in an IPv4 packet informs routers the level of precedence they should apply when processing an incoming packet?

Answer 2

Differentiated Services (DiffServ)

Question 3

What command will list only current connections, including IP addresses and port numbers?

Answer 3

netstat -n

Question 4

What utility is the equivalent to the pathping command on a Linux system?

Answer 4

mtr

Question 5

Which statement regarding the Border Gateway Protocol (BGP) is accurate?

Answer 5

BGP utilizes TCP for communicating updates.

Question 6

In a TCP segment, what field indicates how many bytes the sender can issue to a receiver before acknowledgment is received?

Answer 6

sliding-window

Question 7

Which of the following is not a task handled by a router?

Answer 7

A router forwards broadcasts over the network.

Question 8

The IP connectionless protocol relies on what other protocol to guarantee delivery of data?

Answer 8

TCP

Question 9

You are connected to your network’s Cisco router, and need to verify the route table. What command should you enter?

Answer 9

show ip route

Question 10

Which traceroute command will perform a trace using ICMP echo requests instead of UDP datagrams to the host srv1.mycompany.com?

Answer 10

traceroute -I srv1.mycompany.com

Question 11

What is the purpose of the checksum TCP field?

Answer 11

It allows the receiving node to determine whether the TCP segment became corrupted during transmission.

Question 12

What happens when a router receives a packet with a TTL of 0?

Answer 12

The router drops the packet and sends an ICMP TTL expired message back to the host.

Question 13

In IPv6, what field is used to indicate what sequence of packets from one source to one or multiple destinations a packet belongs to?

Answer 13

flow label

Question 14

What is routing protocol convergence time defined as?

Answer 14

It is the time it takes for the protocol to recognize the best path in the event of a network change.

Question 15

Routing protocols that enable routers to communicate beyond neighboring routers, allowing each router to independently map the network, are known as which type of protocols?

Answer 15

link-state protocols

Question 16

Which routing protocol started as a Cisco proprietary protocol and combines some of the features of a link-state protocol with that of distance-vector protocols?

Answer 16

EIGRP

Question 17

You have been tasked with the replacement of OSPF with EIGRP throughout your organization, which consists of a mixture of Cisco routers and routers from other vendors. What statement is accurate?

Answer 17

EIGRP may not be available on non-Cisco routers.

Question 18

What tcpdump command can be used to filter out all traffic except SSH traffic?

Answer 18

tcpdump port 22

Question 19

Which command will produce statistics about each message transmitted by a host, separated according to protocol type?

Answer 19

netstat -s

Question 20

When using the Routing Information Protocol (RIP), what is the maximum number of hops a message can take between its source and its destination before the destination is considered unreachable?

Answer 20

15

Question 21

What occurs when a collision happens on a network?

Answer 21

Each node on the network waits a random amount of time and then resends the transmission.

Question 22

You have been tasked with maintaining a network that is jumbo frame enabled. What does this mean?

Answer 22

The MTU for the network can be as high as 9198 bytes.

Question 23

What IPv6 field is similar to the TTL field in IPv4 packets?

Answer 23

hop limit

Question 24

If the VLAN tag is present in an Ethernet frame, what is the maximum frame size?

Answer 24

1522 bytes

Question 25

By default, what is the MTU size on a typical Ethernet network?

Answer 25

1500 bytes

Question 26

What routing metric affects a path’s potential performance due to delay?

Answer 26

latency

Question 27

Which statement does NOT accurately describe characteristics of the OSPF protocol?

Answer 27

OSPF requires very little CPU or memory resources.

Question 28

Originally codified by ISO, what does the “intermediate system” in IS-IS (Intermediate System to Intermediate System) stand for?

Answer 28

An IS-IS capable network router.

Question 29

What statement regarding the differences between the Windows tracert utility and the Linux/UNIX/macOS traceroute utility is accurate?

Answer 29

By default, the tracert utility uses ICMP echo requests, while traceroute uses UDP datagrams or TCP SYN messages.

Question 30

In the event of a duplicate MAC address shared by two hosts on a switched network, what statement is accurate?

Answer 30

The hosts will still send and receive traffic, but traffic may not always reach the correct destination.