Chapter 6: IP Addressing

Ipv4 address

a 32-bit dotted decimal address containing a network ID and a host ID

Network ID

an ID which specifies the network the computer is on

Host ID

an unique identifier for a computer on a network

Octet

an 8-bit value, four of which makes up the 32-bit dotted decimal IP address

Dotted decimal notation

The format for expressing an IPv4 address - four decimal numbers separated by periods.

Subnet mask

a 32-bit dotted decimal number, that determines which part of an IP address is the network ID and which part is the host ID.

Logical AND operation

a binary operation in which there are two operands - the result is 0 if either operand is 0 and 1 if both operands are 1, “binary multiplication”

Multicasting

a network communication in which a packet is addressed so that more than one destination can receive it

Host address space

the number of addresses available in an IP network number that can be assigned to hosts

127.0.0.0 network

class A IPv4 address, reserved for the loopback address

Loopback address

an address that always refers to the local computer. This address is used to test TCP/IP functionality on the local computer

Localhost

a reserved name that corresponds to the loopback address in an IP network

Link-local address

an ip address that can be used to communicate only on the local subnet. Cannot be routed to other networks. AKA APIPA

Classful addressing

the use of IP addresses with their default subnet masks

Classful Interdomain Routing (CIDR)

a method of IP addressing in which the network and host IDs are determined by a prefix number that specifies how many bits of the IP address are network bits

CIDR notation

a method of expressing an IP address in the format A.B.C.D/n; n

IP Prefix

a value used to express how many bits of an IP address are network ID bits, usually preceded by a /symbol.

Subnet

Subdivisions of an IP network address space

Subnetting

the process of reallocating bits of an IP address’s host portion to the network portion, creating multiple smaller address spaces

Supernetting

the process of reallocating bits from the IP address’s network portion to the host portion, combining smaller subnets into a larger supernet. Sometimes referred to as “route aggregation” or “route summarization”

Metric

a numeric value that tells the router how “far away” the destination network is.

Multihomed server

a server with two or more NICs, each attached to a different IP network. Network Address Translation

Network Address Translation

a service that translates a private IP address to a public IP address . Is often used to allow using private IP addresses while connected to the Internet.

Port Address Translation

an extension of NAT that allows several hundred workstations to access the internet with a single public internet address using port numbers on the transport layer

Extended Unique Identifier (EUI)-64 Interface ID

an autoconfigured IPv6 host addresses that uses the MAC address of the host plus an additional 16 bits.

Unicast address

an address in a unit of network data intended for a single destination device

Link-local IPv6 addresses

IPv6 addresses that are similar in function to APIPA addresses. IPv6 addresses that begin with fe80, are self-configuring, and cannot be routed.

Unique Local IPv6 Addresses

An IPv6 address for devices on a private network that can’t be routed on the internet. Begins with fc or fd and is usually expressed as fc00

Global IPv6 unicast addresses

IPv6 addresses that are accessible on the public internet and can be routed.

Zero address

an unspecified IPv6 address (

Documentation

The global unicast address 2001

IPv4 to IPv6 transition

a number of address prefixes used for transitioning from IPv4 to IPv6 and to support both on the same network.

Anycast addresses

an address type unique to IPv6 which allows a one-to-many relationship between source and destination

Dual IP layer Architecture

the current architecture of the IPv6 protocol in windows, in which both IPv4 and IPv6 share the other components of the stack

Tunneling

a network protocol technique that allows transmitting a packet in a format that’s otherwise incompatible with the network architecture by encapsulating the packet in a compatible header format.

Intra-site automatic tunnel addressing protocol (ISATAP)

an automatic tunneling protocol used to transmit IPv6 packets between dual IP layer hosts across an IPv4 network.

6to4

an IPv4 to IPv6 transition protocol that provides automatic tunneling of IPv6 traffic over an IPv4 network

Teredo

an automatic IPv6 over IPv4 tunneling protocol that solves the problem of 6to4’s requirement of a public IPv4 address and the inability to traverse NAT routers

128

An IPv6 address is made up of how many bits?

Defines network and host portions of an IP address

The subnet mask of an IP address does which of the following?

Router

Which of the following is needed if a computer with the IP address 172.31.210.10/24 wants to communicate with a computer with the IP address 172.31.209.122/24?

172.19.243.254

Which of the following is a private IP address and can't be routed across the Internet?

route

Which command should you use with a dual-homed server to make sure the server sends packets out the correct interface?

netsh

Which command should you use to configure the primary DNS server on your computer?

10.100.44.123/24

Which IP address expressed in CIDR notation has the subnet mask 255.255.255.0?

172.16.4.0/22

Which IP network address expressed in CIDR notation can support a maximum of 1022 hosts?

False

The IP address 10.240.0.0/8 can't be assigned to a host. True or False?

What's the term for each grouping of 8 bits in an IP address?

Octet

DHCP

Which protocol can configure a computer's IP address and subnet mask automatically?

4

How many bits must be reallocated from a host ID to a network ID to create 16 subnets?

255.255.255.248

For the Class C network address 192.168.10.0, which of the following subnet masks provides 32 subnets?

6

How many host bits are necessary to assign addresses to 62 hosts?

NAT

Which IP addressing process enables workstations to use private IP addresses to access the Internet?

APIPA

When a Windows computer is configured to use DHCP but no DHCP server is available, what type of address is configured automatically for it?

2001:345:abcd::BEEF:44

Which of the following represents a valid IPv6 address?

Use the route command to add routes to the networks that aren't receiving replies.

You have a server with two NICs, each attached to a different IP network. You're having problems communicating with devices on remote networks that send packets to one of the interfaces. The server receives the packets fine, but the server's replies never reach the intended destination network. Replies to packets that come in through the other interface seem to reach their destination without any problems. What can you do that will most likely solve the problem?

ipconfig /flushdns

You have just changed the IP address from 172.31.1.10/24 to 172.31.1.110/24 on a computer named computer5 in your domain. You were communicating successfully with this computer from your workstation before you changed the address. Now when you try the command ping computer5 from your workstation, you don't get a successful reply. Other computers on the network aren't having a problem communicating with the computer. Which command might help solve the problem?

172.16.7.255/22

Which address can't be assigned to a host computer?

Teredo

Which IPv6 transition technology can be used with NAT routers and has the address prefix 2001::/32?

64

How many bits are in the interface ID of an IPv6 address?

::1

What address should you ping if you want to test local IPv6 operation but don't want to actually send any packets on the network?