Computer Networks test on “IPv6 Addressing”.
1. Dual-stack approach refers to _________
a) Implementing Ipv4 with 2 stacks
b) Implementing Ipv6 with 2 stacks
c) Node has both IPv4 and IPv6 support
d) Implementing a MAC address with 2 stacks
Answer: c
Clarification: Dual-stack is one of the approaches used to support IPv6 in already existing systems. ISPs are using it as a method to transfer from IPv4 to IPv6 completely eventually due to the lower number of possible available addresses in IPv4.
2. Suppose two IPv6 nodes want to interoperate using IPv6 datagrams, but they are connected to each other by intervening IPv4 routers. The best solution here is ________
a) Use dual-stack approach
b) Tunneling
c) No solution
d) Replace the system
Answer: b
Clarification: The IPv4 routers can form a tunnel in which at the sender’s side, the IPv6 datagram is encapsulated in to IPv4, and at the receiver’s side of the tunnel, the IPv4 packet is stripped and the IPv6 packet is sent to the receiver.
3. Teredo is an automatic tunneling technique. In each client the obfuscated IPv4 address is represented by bits ______
a) 96 to 127
b) 0 to 63
c) 80 to 95
d) 64 to 79
Answer: a
Clarification: Teredo is a technique through which gives the possibility for full IPv6 network connectivity to IPv6 capable hosts which are currently on an IPv4 network. Bits 96 to 127 in the datagram represents obfuscated 1Pv4 address of the IPv4 network.
4. A link local address of local addresses is used in an _______
a) Isolated router
b) Isolated mask
c) Isolated subnet
d) Isolated net
Answer: c
Clarification: Isolated subnet is very huge sharing network area in this link local address of local addresses is used. A link local address can be configured on any subnet with the prefix “FE80::”.
5. In subcategories of reserved address in IPv6, address that is used by a host to test itself without going into network is called _________
a) Unspecified address
b) Loopback address
c) Compatible address
d) Mapped address
Answer: b
Clarification: In subcategories of reserved address in IPv6, address that is used by a host to test itself without going into network is called loop back address. IPv6 loopback address is 0000:0000:0000:0000:0000:0000:0000:0001. IPv4 loopback address is 127.0.0.1. It’s a reserved address.
6. A few leftmost bits in each address of IPv6 address define its category is called ________
a) Prefix type
b) Postfix type
c) Reserved type
d) Local type
Answer: a
Clarification: Prefix is the bits in the IP address which are placed in leftmost position. A network prefix in IPv6 is given by a CIDR format-liked number at the end of the address.
7. In IPv6 addresses, addresses that start with eight 0s are called ________
a) Unicast addresses
b) Multicast addresses
c) Any cast addresses
d) Reserved addresses
Answer: d
Clarification: In IPv6 address format, the starting bits are specified with eight 0s to represent reserved addresses. These reserved addresses have a certain function pre-defined like the loop-back address is used to test a network card. Reserved addresses cannot be allotted to a machine.
8. Which statement(s) about IPv6 addresses are true?
a) Leading zeros are required
b) Two colons (::) are used to represent successive hexadecimal fields of zeros
c) Two colons (::) are used to separate fields
d) A single interface cannot have multiple IPv6 addresses of different types
Answer: b
Clarification: In order to shorten the written length of an IPv6 address, successive fields of zeros may be replaced by double colons. In trying to shorten the address further, leading zeros may also be removed. Just as with IPv4, a single device’s interface can have more than one address; with IPv6 there are more types of addresses and the same rule applies. There can be link-local, global unicast, and multicast addresses all assigned to the same interface.
9. When was IPv6 launched?
a) June 2, 2012
b) June 4, 2012
c) June 5, 2012
d) June 6, 2012
Answer: d
Clarification: IPv6 is the latest version of the Internet Protocol released on 6th June 2012. An IPv6 address is 128 bits long. Therefore, 2128 i.e. 340 undecillion addresses are possible in IPv6.