Week 9 Flashcards
What is the Transport Layer?
Allows end-to-end transfer of application data
What is the Network Layer?
Allows end-to-end device communication
What is an IPv4 Address?
Uniquely identifies a device on IP network
32-bit broken into four octets using dotted-decimal format
11000000 10101000 00010011 00011111
What are the types of IPv4 Addresses?
Network Address - all host portion bits are 0’s
Broadcast Address - all host portion bits are 1’s
Host Address - Between and broadcast
What is Subnetting?
Dividing a single address block into multiple logical networks
Borrowing bits from host portion to network portion
Number of subnets = 2^b
What are Public Addresses?
Used in networks accessible on the Internet
What are Private Addresses?
Used in internal networks
are not routable on the Internet
What is NAT?
Changes a private IPv4 address to a public address
What is the Internet Control Message Protocol (ICMP)?
A L3 supporting protocol
Messaging protocol - sends messages and operational information
Used for error reporting and diagnosing network issues
Testing connectivity (ping)
Observing the path (tracert)
What was the Internet initially?
was initially a fistful of hosts
What is the Internet of Things (IoT)?
Network of physical objects - “things” - for connecting and exchanging data over the Internet
What is the IoT causing?
An increasing demand for IP addresses
Over the years the number of connected devices worldwide has been sharply increasing from 2019 8.6 billion to 2030 estimated at 29.42 billion!
What is IPv4 Exhaustion?
ARIN’s free pool of IPv4 address space was depleted on September 2015
RIPE NCC announced running out of IPv4 addresses on November 2019
LACNIC have their last available IPv4 address block reserved on August 2020
What are the 3 ways of conserving IP addresses?
CIDR - Classless addressing
Public and private IPs
Network Address Translation (NAT)
What is the step forward for IPv4 Exhaustion?
We are currently transitioning from IPv4 to IPv6
What are the features of IPv6?
Large address space
Simplified header
Built-in security
Jumbograms
What is Large Address Space?
IPv6 addresses consist of 128 bits meaning that the IPv6 address space allows for 250 addresses for every star in the known universe!
How does IPv6 Address Abbreviation work?
2001:0db8:0000:0042:0000:0000:abcd:ef12
Discard Leading Zeroes:
2001:db8:0:42:0:0:abcd:ef12
Double Colon for Consecutive Zeroes – Done once
2001:db8:0:42::abcd:ef12
What is EUI-64 and Interface Identifiers?
EUI-64 automatically generates unique 64 bit interface ID
eg.
MAC Address: 1234 5678 abcd
Interface ID: 1234 56FF FF78 ABCD
^^ ^^
What is Random and Temporary Interface Identifiers?
EUI-62 is no longer recommended due to issues with privacy, instead we use random and temporary interface identifiers
What are the types of IPv6 Addresses?
Multicast
Broadcast
Unicast
Anycast
What are Jumbocasts?
IPv4 / IPv6 allows for internet layer packets with a size of up to 2^16 / 2^32
Using Jumbograms in situations where the risk of transmission failure is low can reduce communication overhead
