IP Addressing

Ping

command used to test connectivity to another host

RA (Router Advertisement) Message

sent by routers to provide addressing information to hosts using SLACC (stateless address autoconfiguration); sent periodically in response to RS messages

Directed broadcast

sent to all hosts on a specific network; useful for sending a broadcast to all hosts on a non-local network

Device Identifier

unique 24 bit (6 hexadecimal digits) value within a common OUI

Multicast (IPv6 Addresses)

(a.k.a. group address) used to send a single IPv6 packet to multiple destinations

Multicast

1.process of sending a packet from one host to a selected group of hosts; possibly in different networks; 2.designed to conserve bandwidth of IPv4 networks; 3.reduces traffic by allowing a host to send a single packet to a selected set of hosts that are part of a subscribing group; 3.used for video and audio broadcasts, 3.routing information exchanged by routing protocols, distribution of software, and remote gaming; 4.address range is 224.0.0.0-239.255.255.255

Broadcast

1.process of sending a packet from one host to all hosts in the network; 2.used for mapping upper layer addresses to lower layer addresses; 3.used for requesting an address

Loopback address

127.0.0.1; special address that hosts use to direct traffic to themselves; you can ping this address to test the configuration of TCP/IP on the local host.

OUI (Organizationally Unique Identifier)

24 bit (6 hexadecimal (base 16 number system) digits) vender code assigned by IEEE

Public address

IPv4 host addresses designated for use in networks that are accessible on the Internet

Anycast (IPv6 Addresses)

IPv6 unicast address that can be assigned to multiple devices; Communication that takes place over a network between a single sender and the nearest of a group of receivers. Anycast is used in IPv6 as a method of updating routing tables. One host initiates an update of a router table for a group of hosts, sending the data to the nearest host. That host then sends the message on to its nearest router until all the routing tables in that group are updated

Tier 3 ISPs

acquire Internet service from Tier 2 ISPs; focus of these ISPs is the retail and home networks in a specific locale; often bundle Internet connectivity as a part of network and computer service contracts for their customers; good choice for small to medium sized companies

Tier 2 ISPs

acquire their Internet service from Tier 1; generally focus on business customers; tend to have the IT resources to operate their own services such as DNS, email servers, and web servers; may offer website development and maintenance, e-commerce/e-business, and VoIP

TEST-NET address

address block 192.0.2.0-192.0.2.255 is set aside for teaching and learning purposes; can be used in documentation and network examples

Class A

address block designed to support extremely large networks with more that 16 million host addresses; range of 0.0.0.0-127.255.255.255 with a 255.0.0.0 or /8 subnet mask

Class B

address block designed to support the need os moderate to large size networks with up to approximately 65000 hosts; range of 128.0.0.0-191.255.255.255 with a 255.255.0.0 or /16 subnet mask

Link-local address

address that can be automatically assigned to the local host by the operating system in environments where no IP configuration is available; used in small peer-to-peer networks or when no IP configuration was obtained from DHCP

Shared address

address that is not globally routable and is intended only for use in service provider networks

Solicited-mode multicast

address that matches only the last 24 bits of the IPv6 global unicast address of a device; automatically created when the global unicast or link-local unicast address is created

Experimental address

addresses in block 240.0.0.0-255.255.255.254 are listed as reserved for future use; can only be used for research and experimental purposes, but cannot be used in an IPv4 network

IPv6

addressing system that uses 128 bits providing for 340 undicillion addresses (number 340 followed by 36 zeros)

Dual Stack (IPv4 to IPv6 Migration Techniques)

allows IPv4 and IPv6 to coexist on the same network; devices run both IPv4 and IPv6 protocol stacks simultaneously

Translation (NAT64) (IPv4 to IPv6 Migration)

allows IPv6 enabled devices to communicate with IPv4 enabled devices using a translation technique similar to NAT for IPv4; IPv6 packet is translated to an IPv4 packet, and vice versa

CIDR (Classless Inter-Domain Routing)

allows service providers to allocate IPv4 addresses on any address bit boundary (prefix length /) instead of only by a class A, B, or C address

Unspecified address (IPv6 Unicast Address)

an all 0s address represented as ::/128 or just :: in the compressed format; cannot be assigned to an interface and is only used as a source address in an IPv6 packet; used as a source address when the device does not yet have a permanent IPv6 address or when the source of the packet is irrelevant to the destination

ANDing

binary operation used in digital logic; comparison of two bits that yields the following results: 1AND1=1, 0AND1=0, 0AND0=0, 1AND0=0

Address pool

block of addresses required by the DHCP server for configuration

Private address

blocks of addresses that are used in networks that require limited or no Internet access

Show ipv6 route

command that can be used to verify that IPv6 networks and specific IPv6 interface addresses have been installed in the IPv6 routing table; shows only IPv6 routes

Show ipv6 interface brief

command that displays abbreviated output for each of the interfaces

Show interface

command that displays the MAC address of the Ethernet interfaces

IPv6 address (IPv6 Unicast Address)

command to configure an IPv6 global unicast address on an interface

Ipconfig

command used toview the IP address information assigned by the DHCP server

Dotted decimal format

each byte of 32 bit IPv4 address is read as a single decimal digit from 0-255

DHCP (Dynamic Host Configuration Protocol)

enables the automatic assignment of addressing information such as IP address, subnet mask, default gateway, and other configuration information

Interface ID (IPv6 Unicast Address)

equivalent to the host portion of an IPv4 address

IPv6 router

forwards IPv6 packetws between networks; can be configured with static IPv6 routes or a dynamic IPv6 routing protocol; sends ICMPv6 RA messages

IPv6 unicast-routing

global configuration command used to enable a router as a IPv6 router

Global unicast (IPv6 Unicast Address)

globally unique, Internet routable address; can be configured statically or assigned dynamically

Multicast client

hosts that receive multicast data

Tier 1 ISPs

large or international ISPs that are directly connected to the Internet backbone; customers of these ISPs are either lower-tier ISPs or large companies or organizations; they engineer highly reliable connections and services; supported by multiple connections to the Internet backbone

RIRs (Regional Internet Registries)

manages IP address allocation for particular purposes or regions; responsible for allocation IP addresses to ISPs

IANA

manages the allocation of IPv4 and IPv6 addresses

ICMPv6 Time Exceeded

message sent if the router cannot forward an IPv6 packet because the packet has expired

ICMP Destination Unreachable

message sent when a host or gateway receives a packet that it cannot deliver

Tunneling (IPv4 to IPv6 Migration Techniques)

method of transporting an IPv6 packet over an IPv4 network; IPv6 packet is encapsulated inside an IPv4 packet, similar to other types of data

SLAAC (Stateless Address Autoconfiguration)

method that allows a device to obtain its prefix, prefix length, and default gateway address information from and IPv6 router without the use of a DHCPv6 server

Class C

most commonly available address block; intended to provide addresses for small networks with a maximum of 254 hosts; range of 192.0.0.0-223.255.255.255 with a subnet mask of 255.255.255.0 or /24

Static address assignment

network administrator must manually configure the network information for a host

Hexadecimal (IPv4 to IPv6 Migration Techniques)

numbering system used to represent IPv6 and MAC addresses; base 16 number system; uses number 0-9 and letters A-F; represented in text by the value preceded by 0x

ISP (Internet Service Provider)

place where most companies or organizations obtain their IPv4 address blocks; provides access to the services of the Internet for individuals, companies, and organizations; provides Internet connectivity, DNS services, email services, and websites.

Global routing prefix (IPv6 Unicast Address)

prefix, or network portion of the address that is assigned by the provider

Unicast

process of sending a packet from one host to an individual host; used for normal host-to-host communication in both a client/server and a peer-to-peer network

EUI-64 process

process that use's a client's 48 bit Ethernet MAC address, and inserts another 16 bits in the middle of the 48 bit MAC address to create a 64 bit Interface ID

Binary notation

representation of information using only ones and zeros

Assigned multicast

reserved multicast address for predefined groups of devices running a common protocol or service; used in context with specific protocols such as DHCPv6

ICMP

sends messages to provide feedback about issues related to the processing of IP packets under certain conditions

DHCPv6

service that automatically assigns addressing information including a global unicast address, prefix length, default gateway address, and the addresses of DNS servers

Subnet mask

signifies which part of the IP address is network and which part is host

Broadcast address

special address for each network that allows communication to all hosts in that network; host portion contains all 1s

Network address

standard way to refer to a network; host portion contains all zeros

Host address

unique address of end device; cannot contain all 0s or all 1s

Unicast (IPv6 Addresses)

uniquely identifies an interface on an IPv6 enable device

Loopback (IPv6 Unicast Address)

used by a host to send a packet to itself and cannot be assigned to a physical interface; used to test the configuration of TCP/IP on the local host; all 0s except for the last bit, represented as :: 1/18 or ::1 in the compressed format

ICMPv4 Time Exceeded

used by a router to indicate that a packet cannot be forwarded because the TTL (time to live or hop limit) field of the packet was decremented to 0

Subnet ID (IPv6 Unicast Address)

used by an organization to identify subnets within its site

Limited broadcast

used for communication that is limited to the hosts on the local network

Unique local (IPv6 Unicast Address)

used for local addressing within a site or between a limited number of sites; should not be routable; range of FC00::/7 to FDFF::/7

Link-local (IPv6 Unicast Address)

used to communicate with other devices on the same local link; with IPv6, the term link means subnet; addresses are configured to a single link; non-routable addresses, so they only have to be unique to the local link

ASCII (American Standard Code for Information Interchange)

used to conver letters to binary code

ICMP Echo Message

used to determine if a host is operational

DAD (Duplicate Address Detection)

used to ensure that an assigned global unicast or link-local unicast address is unique

IPv4 embedded (IPv6 Unicast Address)

used to help transition from IPv4 to IPv6

ICMP Redirect Message

used to notify hosts on a network that a better router is available for a particular location

Address Resolution

used when a device on the LAN knows the IPv6 unicast address of a destination but does not know its Ethernet MAC address

RS (Router Solicitation) Message

used when a host is configured to obtain its addressing information automatically using SLAAC (stateless address autoconfiguration)

Traceroute (tracert)

utility that generates a list of hops that were successfully reached along a path; can provide important verification and troubleshooting information