C7 IP Addressing (WLab & Review ?s)

IANA (Internet Assigned Numbers Authority)

A nonprofit, United States government-funded group that was established at the University of Southern California and charged with managing IP address allocation and the domain name system. The oversight for many of IANA's functions was given to ICANN in 1998; however, IANA continues to perform Internet addressing and domain name system administration.

You want to ping the loopback address of your local host. Which two addresses could you type? (Choose two.) A. ping 127.0.0.1 B. ping 0.0.0.0 C. ping ::1 D. trace 0.0.::1

A, C. The loopback address with IPv4 is 127.0.0.1. With IPv6, that address is ::1.

What is the result of converting 192.168.0.1 to binary? A. 11000000.10101000.00000000.00000001 B. 11000000.10101000.00000000.10000000 C. 11000000.10101000.00000000.1 D. 11.10101.0.1

A. 11000000.10101000.00000000.00000001 is the binary conversion of 192.168.0.1.

What is the private address range for Class B networks?

172.16.0.0 through 172.31.255.255.

Regarding IPv6: IPv4 has a loopback address of 127.0.0.1. What is the IPv6 loopback address?

::1

unique local address

A type of IPv6 unicast address meant as a replacement for IPv4 private addresses. A unique local address (ULA) is an Internet Protocol version 6 (IPv6) address in the address range fc00::/7.[1] Its purpose in IPv6 is somewhat analogous to IPv4 private network addressing, but with significant differences. Unique local addresses may be used freely, without centralized registration, inside a single site or organization or spanning a limited number of sites or organizations. They are routable only within the scope of such private networks, but not in the global IPv6 Internet.

In which order are packets created and sent when a client requests an IP address from a DHCP server? A. DHCP Discover, DHCP Offer, DHCP Request, DHCP ACK B. DHCP Discover, DHCP Request, DHCP Offer, DHCP ACK C. DHCP Request, DHCP Offer, DHCP Discover, DHCP ACK D. DHCP Request, DHCP Offer, DHCP ACK, DHCP Discover

A. DHCP Discover, DHCP Offer, DHCP Request, DHCP ACK (remember DORA) is the correct order.

What defines a unicast address?

An IP address assigned to a single interface.

link-local unicast address

An IPv6 address that can be used for communicating with nodes in the same link. These addresses are similar to IPv4's autoconfigured APIPA addresses and begin with the prefix FE80::/10.

Regarding IPv6: Which type of address identifies multiple interfaces, but packets are delivered only to the first address it finds?

Anycast

What two statements about IPv4 and IPv6 addresses are true? (Choose two.) A. An IPv6 address is 32 bits long, represented in hexadecimal B. An IPv6 address is 128 bits long, represented in decimal C. An IPv4 address is 32 bits long, represented in decimal D. An IPv6 address is 128 bits long, represented in hexadecimal

C, D. IPv4 addresses are 32 bits long and are represented in decimal format. IPv6 addresses are 128 bits long and represented in hexadecimal format.

Which of the following are private IP addresses? (Choose two.) A. 12.0.0.1 B. 168.172.19.39 C. 172.20.14.36 D. 172.33.194.30 E. 192.168.24.43

C, E. The Class A private address range is 10.0.0.0 through 10.255.255.255. The class B private address range is 172.16.0.0 through 172.31.255.255, and the Class C private address range is 192.168.0.0 through 192.168.255.255.

In a Class C IP address, how long is the network address? A. 8 bits B. 16 bits C. 24 bits D. 32 bits

C. A default Class C subnet mask is 255.255.255.0, which means that the first three octets, or the first 24 bits, are the network number.

Which of the following is true when describing an anycast address? A. Packets addressed to a unicast address from an anycast address are delivered to a single interface B. Packets are delivered to all interfaces identified by the address. This is also called a one-to-many address C. This address identifies multiple interfaces, and the anycast packet is delivered to only one address: the closest one. This address can also be called one-to-nearest D. These addresses are meant for nonrouting purposes, but they are almost globally unique so it is unlikely they will have an address overlap

C. Anycast addresses identify multiple interfaces, which is the same as multicast; however, the big difference is that the anycast packet is delivered to only one address: the first one it finds defined in terms of routing distance. This address can also be called one-to-one-of-many or one-to-nearest.

Which of the following is an invalid IP address for a host? A. 10.0.0.1 B. 128.0.0.1 C. 224.0.0.1 D. 172.0.0.1

C. Option C is a multicast address and cannot be used to address hosts.

Which of the following is a valid Class B address? A. 10.1.1.1 B. 126.1.1.1 C. 129.1.1.1 D. 192.168.1.1

C. The Class B range is 128 through 191 in the first octet/byte. Only option C is a valid Class B address.

Which of the following is a valid loopback address? A. 128.0.0.1 B 127.0.0.0 C. 128.0.0.255 D. 127.24.0.1

D. 12.24.0.1 Any address in the 127.0.0.0/8 subnet will work as a loopback.

Which of the following is a valid Class A address? A. 191.10.0.1 B. 127.10.0.1 C. 128.10.0.1 D. 126.10.0.1

D. The Class A range is 1 through 126 in the first octet/byte, so only option D is a valid Class A adress.

multilayer switch operates in which layers?

Layer 2 (Data Link Layer) & Layer 3 (Network Layer)

What is the 127.0.0.1 address used for?

Loopback or diagnostics.

If DHCP goes down?

- APIPA addresses 169.254.x.x will be handed out - we can run an ipconfig /renew (cld have to release first)

Which of the following is a Class C network address? A. 10.10.10.0 B. 127.0.0.1 C. 128.0.0.0 D. 192.255.254.0

D. Only option D is in the Class C range of 192 through 223. It might look wrong because there is a 255 in the address, but this is not wrong - you can have a 255 in a network address, just not in the first octet.

Name some benefits of IPv6 over IPv4.

IPv6 has the following characteristics, among others, that make it preferable to IPv4; more available addresses, simpler header, options for authentication, and other security.

An IPv4 address uses 32 bits. How many bits is an IPv6 address? A. 64 B. 128 C. 192 D. 255

B. An IPv6 address is 128 bits in size.

Regarding IPv6: What does a link-local address always start with?

FE80::/10 In the Internet Protocol Version 6 (IPv6), the address block fe80::/10 has been reserved for link-local unicast addressing

What is the valid range used for a Class C private IP address?

The class C private range is 192.168.0.0 through 192.168.255.255.

Regarding IPv6: Which type of packet is addressed and delivered to only a single interface?

Unicast

What is the Class C range of values for the first octet in decimal and in binary?

192.0.0.0 - 223.255.255.255 11000000.00000000.00000000.00000000 - 11011111.11111111.11111111.11111111

Convert the following MAC address into a EUI-64 address: use the prefix 2001:db8:1:1/64 060c:32f1:a4d2

2001:db8:1:1:040c:32ff:fef1:a4d2

Convert the following MAC address into a EUI-64 address: use the prefix 2001:db8:1:1/64 0b0c:abcd:1234

2001:db8:1:1:090c:abff:fecd:1234

Convert the following MAC address into a EUI-64 address: use the prefix 2001:db8:1:1/64 0d01:3a2f:1234

2001:db8:1:1:0f01:3aff:fe2f:1234

APIPA (Automatic Private IP Addressing)

A (Windows feature) service that enables a DHCP client computer to configure itself automatically with a link-local IP address on the 169.254.0.0 (from 169.254.0.1 to 169.254.255.254) network in case no DHCP servers respond to the client's DHCP discover broadcast. Uses a subnet mask of 255.255.0.0

What is the name for a 48-bit (6-byte) numerical address physically assigned to a network interface, such as a NIC?

A MAC address, sometimes called a hardware address or even a burned-in address. Physical address

What processes are used to take a single class of IP addresses and chop it up into multiple smaller groups? (Select two.) A. CIDR B. ping C. Subnetting D. Subnitting

A and C. Classless Inter-Domain Routing (CIDR) and subnetting enable you to take a single class of IP addresses and chop it up into multiple smaller groups called subnets.

divides collision domains into smaller ones, NOT the broadcast domains

A layer 2 switch

Regarding IPv6: Which addressing type is also referred to as one-to-nearest?

Anycast delivers a message to any one out of a group of nodes, typically the one nearest to the source using a one-to-one-of-many[1] association where datagrams are routed to any single member of a group of potential receivers that are all identified by the same destination address. The routing algorithm selects the single receiver from the group based on which is the nearest according to some distance or cost measure.

Which of the following is a Layer 2 broadcast? A. FF.FF.FF.EE.EE.EE B. FF.FF.FF.FF.FF.FF C. 255.255.255.255 D. 255.0.0.0

B. A Layer 2 broadcast is also referred to as a MAC address broadcast, which is in hexadecimal and is FF.FF.FF.FF.FF.FF.

IPv6 multicast address prefix

FF00::/8 All IPv6 multicast addresses share the prefix of FF00::/8. The first octet is FF (1111 1111).

link-local address (IPv4 and IPv6)

In computer networking, a link-local address is the IP address that is to be used for communication within a logical division of the network or in the broadcast domain to which the host is connected. (same link) The uniqueness in addresses is not assured in another network segment. Therefore, routers DO NOT FWD link-local addresses. The other devices connected to the same physical (or logical) link can communicate using IPv4 Link-Local addresses. IPv4 Connection-Local communication isn't appropriate for communication with gadgets that are not genuinely associated with a similar connection. The IP address reaches to be utilized for these addresses lies in the scope of 169.254.1.0 to 169.254.254.255. APIPA The total addresses some others out to be 65,023 in the range given in the above point. Every interface in IPv6 must have a link-local address. The link-local address is used between point-to-point interfaces as point-to-point communication is carried out between point-to-point interfaces that eliminate the need for a global IPv6 address. Furthermore, routers do not forward these addresses as they are used only on a single link. These are also used for neighbor discovery. FE80:: /64

Regarding IPv6: Which type of address is meant to be delivered to multiple interfaces?

Multicast

What gives IPv6 the ability to reference more addresses than IPv4?

The fact that is has 128-bit (16-octet) addresses, compared to IPv4's 32-bit (4-octet) addresses.

Regarding IPv6: Which type of address is not meant to be routed to the internet but is still globally unique?

Unique local (unicast) (used to be called site-local) In IPv6, Unique Local (unicast) Addresses (ULA) are globally unique addresses that permit communication between nodes on different links within the same site or between sites. They are administratively segmented and are not for routing on the Internet. The ULA is somehow similar with the private IPv4 space.

Eric sits down at a client's Windows computer that's having some network connectivity issues. He wants to start troubleshooting by viewing both the system's IP address and MAC address. What command should he use? A. ifconfig B. ip addr C. ipconfig D. ipconfig /all

D. In Windows, the ipconfig /all command and switch will show both the IP address and the MAC address of a system.

Which of the following addresses is not allowed on the internet? A. 191.192.168.1 B. 191.168.169.254 C. 172.32.255.0 D. 172.31.12.251

D. The addresses in the range 172.16.0.0 through 172.31.255.255 are all considered private; based on RFC 1918. Use of these addresses on the internet is prohibited so that they can be used simultaneously in different administrative domains without concern for conflict. Some experts in the industry believe these addresses are not routable, which is not true.

Regarding IPv6: Which type of address is not meant to be routed?

Every interface in IPv6 must have a link-local address. The link-local address is used between point-to-point interfaces as point-to-point communication is carried out between point-to-point interfaces that eliminate the need for a global IPv6 address. Furthermore, routers do not forward these addresses as they are used only on a single link (subnetwork that the host is connected to). These are also used for neighbor discovery. FE80::/10 In the Internet Protocol Version 6 (IPv6), the address block fe80::/10 has been reserved for link-local unicast addressing

Regarding IPv6: What does a unique local unicast range start with?

FC00:: /7 The first seven bits represents the Prefix, which according to the RFC is FC00::/7; https://www.ateam-oracle.com/post/oci-unique-local-ipv6-unicast-addresses-ula#:~:text=Unique%20Local%20Addresses%20(ULA)%20are,with%20the%20private%20IPv4%20space.

link-local address vs unique local address

link-local addresses are not meant to be routed and are unique to each link(LAN). unique-local-address are also intended for nonrouting purposes. IPv6 link-local addresses are defined by RFC 4291 (IPv6 Addressing Architecture) and are covered by the prefix fe80::/10. In practice, only fe80::/64 is used.

What defines a multicast address?

packets addressed to a multicast address are delivered to all interfaces identified by the multicast address. aka One-to-many address. unicast, multicast and broadcast happen at layer-2 and layer-3. https://www.thestudygenius.com/unicast-broadcast-multicast/

Convert the following MAC address into a EUI-64 address: use the prefix 2001:db8:1:1/64 0a0c:abac:caba

2001:db8:1:1:080c:abff:feac:caba

Convert the following MAC address into a EUI-64 address: use the prefix 2001:db8:1:1/64 10bc:abcd:1234

2001:db8:1:1:12bc:abff:fecd:1234

Which of the following is true when describing a unicast address? A. Packets addressed to a unicast address are delivered to a single interface B. These are your typical publicly routable addresses, just like regular publicly routable addresses in IPv4 C. These are like private addresses in IPv4 in that they are not meant to be routed. D. These addresses are meant for nonrouting purposes, but they are almost globally unique, so it is unlikely they will have an address overlap

A. Packets addressed to a unicast address are delivered to a single interface. For load balancing, multiple interfaces can use the same address. A unicast address uniquely identifies a single interface by its address. An interface can have multiple unicast addresses and must have at least one link-local address. A link-local address is an address used on a link between two nodes. In some cases, link-local addresses are sufficient if the node does not need to send packets beyond a local link. Note that a node may assign a unicast address (or a set of unicast addresses) to more than one interface if and only if it treats them as one interface when presenting to the network layer. This could be useful to load balance traffic over a set of physical interfaces.

What is the term for the autoconfiguration technology responsible for addresses that start with 169.254?

Automatic Private IP Addressing (APIPA) is the technology that results in hosts automatically configuring themselves with addresses that begin with 169.254. This allows the dynamic clients on a single network to continue to communicate with each other bc they are on the same network ID. (aka Link-local) APIPA will never issue a default gateway , so you'll never get on the internet. Even if you are in the same network, you can only communicate with those computers that came up after the DHCP server went down. (you cannot communicate with those that retain a DHCP IP address).

Which of the following are not valid IP addresses to assign to a Windows-based system? (Select two.) A. 10.1.1.1/24 B. 127.0.0.1/24 C. 250.250.250.255/24 D. 192.168.0.1/24

B and C. The special reserved IP address 127.0.0.1 is called the loopback address and is used for testing, not assigning to computers. The IP address 250.250.250.255 falls in the Class E range, which isn't assigned to hosts.

Which statements about subnet masks are true? (Select two.) A. Every network client has a unique subnet mask. B. Every client on a network shares the same subnet mask. C. A subnet mask consists of a string of zeroes followed by a string of ones. D. A subnet mask consists of a string of ones followed by a string of zeroes.

B and D. Every client on a network shares the same subnet mask. Subnet masks consist of a string of ones followed by a string of zeroes.

What two statements about IPv6 addresses are true? (Choose two.) A. Leading zeroes 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 will have multiple IPv6 addresses of different types

B, D. 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 at the same interface.

A host automatically configured with an address from which of the following ranges indicates an inability to contact a DHCP server? A. 169.254.0.x with a mask of 255.255.255.0 B. 169.254.x.x with a mask of 255.255.0.0 C. 169.254.x.x with a mask of 255.255.255.0 D. 169.255.x.x with a mask of 255.255.0.0

B. APIPA uses the link-local private address range of 169.254.0.0 through 169.254.255.255 and a subnet mask of 255.255.0.0. APIPA addresses are used by DHCP clients that cannot contact a DHCP server and have no static alternate configuration. These addresses are not internet routable and cannot, by default, be used across routers on an internetwork.

Which of the following describes a broadcast address? A. All network bits are on (1s) B. All host bits are on (1s) C. All network bits are off (os) D. All host bits are off (0s)

B. If you turned on all host bits (all of the host bits are 1s), this would be a broadcast address for that network.

Which of the following is true when describing a multicast address? A. Packets addressed to a unicast address from a multicast address are delivered to a single interface B. Packets are delivered to all interfaces identified by the address. This is also called a one-to-many address C. It identifies multiple interfaces and is delivered to only one address. This address can also be called one-to-one-of-many D. These addresses are meant for nonrouting purposes, but they are almost globally unique so it is unlikely they will have an address overlap

B. Packets addressed to a multicast address are delivered to all interfaces identified by the multicast address, the same as in IPv4. A multicast address is also called a one-to-many address. You can tell multicast addresses in IPv6 because they always start with FF.

A host is rebooted and you view the IP address that it was assigned. The address is 169.123.13.34. Which of the following happened? A. The host received an APIPA address B. The host received a multicast address C. The host received a public address D. The host received a private address

C. I wonder how many of you picked APIPA address as your answer? An APIPA address is 169.254.x.x. The host address in this question is a public address. Somewhat of a tricky question if you did not read carefully. APIPA ranges from 169.254.1.0 to 169.254.254.255

Which statement regarding private IP addresses is most accurate? A. Private addresses cannot be used in intranets that require routing B. Private addresses must be assigned by a registrar or ISP C. A remote host across the internet cannot ping your host if it has a private address D. Private addresses can only be used by a single administrative domain

C. Private IP addresses are not routable over the internet, as either source or destination addresses. Because of that fact, any entity that wishes to use such addresses internally can do so without causing conflicts with other entities and without asking permission of any registrar or service provider. Despite not being allowed on the internet, private IP addresses are fully routable on private intranets.

Regarding IPv6: Which type of address is used just like a regular public routable address in IPv4?

Global unicast address (GUA)

4 steps of network diagnosing

You ping the addresses in the following order: 1- loopback 2- NIC 3- default gateway 4- router