5 - TCP/IP Protocols - Self Test

Which of the following protocols are layer-4 protocols? (Select all that apply.) A. TCP B. IP C. ARP D. UDP

*A and D*. TCP and UDP are transport protocols. TCP is responsible for connection-oriented communication and error-free delivery, whereas UDP is responsible for connectionless communication. B and C are incorrect. IP is a network-layer protocol, and ARP is a layer-2 protocol.

How many bits in an IPv6 address? A. 128 bits B. 32 bits C. 48 bits D. 256 bits

*A*. An IPv6 address is made up of 128 bits that are organized into 16-bit blocks separated by a colon (:). Each 16-bit block is made up of a 4-bit hexadecimal character. An example IPv6 address is fe80:0000:0000:0000:b596:cafa:5ea1:cbf0. B, C, and D are incorrect, as they are not the length of an IPv6 address.

Which protocol is responsible for error reporting and status information? A. ICMP B. TCP C. UDP D. IP

*A*. ICMP is responsible for reporting errors and sending back status information when communicating over TCP/IP. B, C, and D are incorrect. TCP is used for connection-oriented communication, UDP is used for connectionless communication, and the IP protocol is used to deliver the packets.

Which network service is responsible for hiding internal network resources by changing the source address of every outbound packet? A. NAT B. NFS C. SMB D. Samba

*A*. NAT is used to translate the source address of an outgoing packet to that of the external interface of the NAT server. B, C, and D are incorrect. NFS is the protocol that allows UNIX clients to connect to the remote file system of other UNIX (NFS) systems. SMB is the protocol in Microsoft environments that allows Microsoft clients to connect to the file system of other Microsoft systems. Samba is the service loaded on UNIX systems to allow Microsoft clients to access resources of the UNIX server.

Which network service is responsible for allowing Microsoft clients to access the file system on Microsoft servers? A. SMB B. NFS C. NAT D. Samba

*A*. SMB is the protocol in Microsoft environments that allows Microsoft clients to connect to the file system of other Microsoft systems. B, C, and D are incorrect. NFS is the protocol that allows UNIX clients to connect to the remote file system of other UNIX (NFS) systems. NAT is used to translate the source address of an outgoing packet to that of the external interface of the NAT server. Samba is the service loaded on UNIX systems to allow Microsoft clients to access resources of the UNIX server.

Which protocol is responsible for connection-oriented communication? A. TCP B. IP C. UDP D. ICMP

*A*. TCP is responsible for connection-oriented communication in the TCP/IP protocol suite. B, C, and D are incorrect. IP is used for packet delivery, UDP is used for connectionless communication, and ICMP is used for error reporting and status display.

Which of the following identify benefits of IPv6 over IPv4? (Select three.) A. Auto-configuration B. Decreased address space C. No broadcast messages D. Increased address space E. More broadcast messages

*A, C, and D*. There are a number of benefits to IPv6, such as increased number of addresses, auto-configuration, and no broadcast messages. B and E are incorrect, as IPv6 has not decreased the address space or increased the number of broadcast messages.

Jeff is one of the network administrators in your office and he says that he noticed his Windows 8 desktop has a link-local address assigned. Which of the following addresses is his Windows 8 system using? A. ::1 B. fe80::b596:cafa:5ea1:cbf0 C. 2001::b596:cafa:5ea1:cbf0 D. FF01:0:0:0:0:0:0:2

*B*. A link-local address is automatically assigned to a Windows 8 system and is an address that starts with FE80. A, C, and D are incorrect. ::1 is the loopback address in IPv6, while addresses that start with 2001 are global addresses. An address that starts with FF01 is a multicast address in IPv6.

Which layer of the OSI model does the IP protocol run at? A. Layer 2 B. Layer 3 C. Layer 4 D. Layer 5

*B.* The IP protocol is responsible for logical addressing and routing,which is a function of layer 3 of the OSI model. A, C, and D are incorrect. The IP protocol does not run at those layers or perform their functions.

Which of the following represents an IPv6 global address? A. ::1 B. fe80::b596:cafa:5ea1:cbf0 C. 2001::b596:cafa:5ea1:cbf0 D. FF01:0:0:0:0:0:0:2

*C*. A global address in IPv6 is equivalent to an IPv4 public address and has 2001 as a prefix. A, B, and D are incorrect. ::1 is the compressed version of a loopback address, link-local addresses start with FE80, and addresses that start with FF01 are multicast addresses.

Which network service is responsible for assigning IP addresses to clients on the network? A. NAT B. WINS C. DHCP D. NFS

*C*. DHCP is responsible for assigning IP addresses to clients on the network. A, B, and D are incorrect. NAT is used to translate the source address of an outgoing packet to that of the external interface of the NAT server. WINS is used to convert computer names (NetBIOS names) to IP addresses. NFS is the protocol that allows UNIX clients to connect to the remote file system of other UNIX (NFS) systems.

Which protocol is responsible for logical addressing and delivery of packets? A. ICMP B. TCP C. IP D. UDP

*C*. IP is responsible for packet delivery and logical addressing. A, B, and D are incorrect. ICMP is used for error reporting, TCP is used to ensure that the packet reaches the destination, and UDP is used for connectionless communication.

Which protocol is responsible for converting the IP address to a MAC address? A. IP B. TCP C. ARP D. ICMP

*C*. The Address Resolution Protocol (ARP) is responsible for converting an IP address to a MAC address so that communication can occur. A, B, and D are incorrect. IP is used for packet delivery, TCP is used for ensuring packet delivery, and ICMP is used for error reporting and status reporting.

Which network service is responsible for allowing Microsoft clients access to the file system on a UNIX server? A. NAT B. NFS C. SMB D. Samba

*D*. Samba is responsible for allowing Microsoft clients to access resources on the UNIX system because Samba implements the SMB protocol. A, B, and C are incorrect. NAT is used to translate the source address of an outgoing packet to that of the external interface of the NAT server. NFS is the filesharing protocol on UNIX systems, and SMB is the file-sharing protocol used between Microsoft operating systems.

Which of the following tunneling protocols would you use to tunnel IPv6 packets in an IPv4 packet when sitting behind a NAT device? A. 6to4 B. ISATAP C. 4to6 D. Teredo

*D*. Teredo is a tunneling protocol that works behind a NAT device when tunneling IPv6 packets inside IPv4 packets. A, B, and C are incorrect, as they are tunneling protocols but do not work behind a NAT device.

Which protocol is responsible for sending e-mail across the Internet? A. POP3 B. IMAP4 C. HTTP D. SMTP

*D*. The Simple Mail Transport Protocol (SMTP) is responsible for sending mail across the Internet. A, B, and C are incorrect. POP3 and IMAP are e-mail protocols, but they are standards for reading e-mail, not sending e-mail. HTTP is the protocol used by web browsers to receive webpages from the web server.