IPv4 and IPv6
IPv4: Loopback Address
127.0.0.0
IPv6 address length
128 bit length
IPv6: Loopback Address
The unicast address 0:0:0:0:0:0:0:1 Node to send an IPv6 packet to itself must not be assigned to any physical interface.
IPv6 address simplification rules
Discard the leading zeros If two of more blocks contain consecutive zeroes, omit them all and replace with double colon sign ::
IPv6: Link Local Address
FE80::/10
IPv4: APIPA Address
169.254.0.0 to 169.254.255.255
Subnet Mask
A 32-bit number used to differentiate the network component of an IP address by dividing the IP address into a network address and host address. It does so with bit arithmetic whereby a network address is bit multiplied by the __________ reveal the underlying subnetwork. Like the IP address, a subnet mask is written using the "dotted-decimal" notation.
IPv4: Multicast address
Address represents a group of devices. If an IP packet is sent on a __________ address, it is intended for all members of that group. Addresses are usually used by networking devices for running their own services.
IPv4: Broadcast address
Address represents all devices of the network. If an IP packet is sent on a __________ address, it is intended for all devices of that network. Addresses are usually used to locate hosts or services in network.
IPv4: Unicast Address
Address represents an individual end device. If an IP packet is sent on a __________ address, it is intended only for that particular recipient. Addresses are usually used by end devices for end to end communication.
IPv4: Private IP Address
Addresses are used in private networks, which are not generally connected to the internet. The same IPs can be used in different networks and maintaining the uniqueness within the network is enough. Can be freely used without any registration.
IPv6: Unique Local Address
Addresses begin with FD00::/8
Classless Addressing rules
All the IP addresses in the CIDR block must be contiguous. The block size should be presentable as a power of 2. Moreover, the number of IP addresses in the block is equivalent to the size. First IP address of the block must be dividable by the block size.
EUI-64 Address Format
Allows a host to assign itself a unique interface identifier. Uses the MAC address in forming the address.
Variable Length Subnet Mask (VLSM)
Allows a network administrator to use long masks for networks with few hosts and short masks for networks with multiple hosts. A _____ is used with a _____ router and must have routing protocol support.
Classful Addressing
An IP address allocation method that allocates IP address according to five major classes. Less practical and useful. Network ID and Host ID changes depending on the classes.
Classless Addressing
An IP address allocation method that is designed to replace classful addressing to minimize the rapid exhaustion of IP addresses. More practical and useful. There is no boundary on network ID and host ID.
IPv4: Class A Private IP Address Range
From 10.0.0.0 to 10.255.255.255
IPv4: Class B Private IP Address Range
From 172.16.0.0 to 172.31.255.255
IPv4: Class C Private IP Address Range
From 192.168.0.0 to 192.168.255.255
Organizationally Unique Identifier (OUI)
Globally unique assigned number. Assigned with a MA-L identifier block and is referenced by various standards. It can be used to identify an organization or company which requires a globally unique identifier.
Discontiguous network
Classful networks connected with Classless networks.
IPv4: Public IP Address
IP address is globally unique to the Internet. This IP address management is done by the organization called Internet Assigned Numbers Authority (IANA) where they assign IP ranges to different organizations.
IPv6: Anycast Address
Identifies one or more interfaces. For example, servers that support the same function can use the same unicast IP address. Packets sent to that IP address are forwarded to the nearest server. Often used for load-balancing. Known as one-to-nearest address. Address can exist more than once in your network and be assigned to multiple interfaces.
IPv6 improvement freatures
Large address space: uses 128-bit addresses Enhanced security: IPSec (Internet Protocol Security) is built into the protocol Header improvements: header is not protected by a checksum so routers do not need to calculate a checksum for every packet. No need for NAT Stateless address autoconfiguration
Frame
Layer 2 technology Data Link Layer Protocol Data Unit (PDU) Includes the Source and Destination MAC Address
MAC Address
Layer 2 technology Unique identifier for an Ethernet or network adapter over a network. It distinguishes different network interfaces and is used for a number of network technologies, particularly most IEEE 802 networks, including Ethernet. 48 hexadecimal address
IPv4 Address size
Layer 3 technology A logical numeric address that is assigned to every single computer, printer, switch, router or any other device that is part of a TCP/IP-based network. 32 bit length binary address
Packet
Layer 3 technology Network Layer Protocol Data Unit (PDU) Includes the Source and Destination IP Address
Stateless Address Auto-Configuration (SLAAC)
Method in which the host or router interface is assigned a 64-bit prefix, and then the last 64 bits of its address are derived by the host or router Uses NDP protocol to work.
IPv6 recommend structure
Network Portion of 64 bits Interface Identifier of 64 bits
Classless Interdomain Routing (CIDR)
Often referred to as supernetting, where the principles of subnetting are applied to larger networks. Written out in a network /mask format, where the mask is tacked onto the network address in the form of the number of bits used in the mask.
MAC Address parts
Organizationally Unique Identifier (OUI) 3 bytes (24 bits) Network Interface Controller (NIC) Specific 3 bytes (24 bits)
IPv6: Global Unicast
Publicly routable IPv6 addresses that work just like public IPv4 addresses.
Class A address range
Range of 0.0.0.0 to 127.255.255.255. This class is for large networks and has 8 bits for network and 24 bits for hosts.
Class B address range
Range of 128.0.0.0 to 191.255.255.255. This class is for medium networks and has 16 bits for network and 16 bits for hosts.
Class C address range
Range of 192.0.0.0 to 223.255.255.255. This class is for smaller networks and has 24 bits for network and 8 bits for hosts.
IPv6: Multicast Address
Represents a dynamic group of hosts. Have a similar purpose as their counterparts in IPv4 and packets sent to these addresses are delivered to all interfaces tuned into the __________________.
IPv6: Unicast Address
Represents a single interface. Similar to IPv4 type Packets addressed to a _____________ address are delivered to a single interface.
IPv6: Unique Local
Similar to IPv4 private addresses Should be used inside an organization and are not meant to be routed on the Internet. But can be routed inside a local network
IPv6: Link Local
Similar to the IPv4 addresses from the Automatic Private IP Address (APIPA) range, these addresses are meant to be used only within a network segment that a host is connected to. Routers will not forward packets destined to a __________ address to other links. Address must be assigned to every network interface on which the IPv6 protocol is enabled.
Route Summarization
The ability to take a group of subnetworks and summarize them, on the router, as one network route
IPv6: Global Unicast Address
addresses start with 2000::/3 (hex 2 or 3) subnet ID - 64 bits long. Contains the site prefix (obtained from a Regional Internet Registry) and the subnet ID (subnets within the site). interface ID - 64 bits long. It acts like the IPv4 host field and is typically composed of a part of the MAC address of the interface.