Network Fundamentals: Ch6 - Addressing the Network IP v4

Suez Canal University – Faculty of Computers & Informatics - Cisco Local Academy

Network Fundamentals

CH6: ADDRESSING THE NETWORK IP V4

Abdelkhalik Elsaid [email protected]

http://abdelkhalik.staff.scuegypt.edu.eg/

mailto:[email protected]

http://abdelkhalik.staff.scuegypt.edu.eg/


IP v4


IP v4

32 Bits

255 255 255 255

Dotted Decimal Network Host

11111111 11111111 11111111 11111111

12

86

43

21

6 8 4 2 1

12

86

43

21

6 8 4 2 1

12

86

43

21

6 8 4 2 1

12

86

43

21

6 8 4 2 1

192 168 171 221

11000000 10101000 10101011 11011101

Maximum

Binary

Ex. Decimal

Ex. Binary


Types of addresses in IP v4 network



• Network address: The address by which we refer to the network, all host bits are “0”.

• Broadcast address: A special address used to send data to all hosts in the network, all host bits are “1”.

• Host addresses: The addresses assigned to the end devices in the network “values between network and broadcast”.

192 168 171 0

11000000 10101000 10101011 00000000

192 168 171 255

11000000 10101000 10101011 11111111

192 168 171 From 1 to 254

11000000 10101000 10101011 00000001 to11111110



• Prefix Length: the number of bits in the address that gives us the network portion. Ex: 192.168.171.221/24

• Subnet Mask: consists of 32 bits and uses 1s to represent network portion and 0s to represent host portion. Ex: 255.255.255.0


Unicast, Multicast, Broadcast – Types of Communication

• Unicast: the process of sending a packet from one host to an individual host “One-to-One”.

• Multicast: the process of sending a packet from one host to a selected group of hosts “One-to-Many”.Multicast clients: Hosts that wish to receive multicast data, and

must subscribe to a Multicast Group.• Broadcast: the process of sending a packet from one host to all

hosts in the network “One-to-All”. 1.Directed Broadcast: is sent to all hosts on a specific network.

Ex: 192.168.171.255/242.Limited Broadcast: is used for communication that is limited to

the hosts on the local network. Ex: 255.255.255.255


Reserved IP v4 address range

• Host Addresses: 0.0.0.0 to 223.255.255.255Within this range there are many addresses that are already

reserved for special purposes.

• Multicast Addresses (224.0.0.0 to 239.255.255.255):1. Reserved link local addresses: 224.0.0.0 to 224.0.0.255.

Used for multicast groups on a local network.2. Globally scoped addresses: 224.0.1.0 to 238.255.255.255.

Used to multicast data across the Internet.3. Administratively scoped addresses: 239.0.0.0/8 (limited scope).

Used by ISPs to send multicast data to their subscribers.

• Experimental Addresses: 240.0.0.0 to 255.255.255.254 (RFC 3330).


Public and Private addresses

• Public addresses: designated for use in networks that are accessible on the Internet.

• Private addresses: used for internal networks and not routable on the Internet. The private address blocks are:

1. 10.0.0.0 to 10.255.255.255 (10.0.0.0 /8)2. 172.16.0.0 to 172.31.255.255 (172.16.0.0 /12)3. 192.168.0.0 to 192.168.255.255 (192.168.0.0 /16)

NAT allows the hosts in the network to "borrow" a public address for communicating to outside networks.

http://whatismyipaddress.com/http://show-ip.net/

http://www.whatismyip.com/


Public and Private addresses


Special IP v4 Addresses

• Network and Broadcast Addresses:Within each network the first and last addresses cannot be

assigned to hosts.• Default Route: 0.0.0.0, all (0.0.0.0 /8) address block is reserved.

The default route is used as a "catch all" route when a more specific route is not available.

• Loopback: 127.0.0.0 - to - 127.255.255.255.Hosts use loopback to direct traffic to themselves.

• Link-Local Addresses: 169.254.0.0 to 169.254.255.255Automatically assigned by OS where no IP config. is available.

• TEST-NET Addresses: 192.0.2.0 to 192.0.2.255 (192.0.2.0 /24).is set aside for teaching and learning purposes.


Special IP v4 Addresses


Classful Addressing

Classful allocation of address space often wasted many addresses, which exhausted the availability of IPv4 addresses. Classless Addressing solves this problem


Fill in the information…

1. 192.168.1.3 Class ------- Default Mask: ---------------Network: ------------------- Broadcast: -------------------

Hosts: ----------------------through-----------------------

2. 1.12.100.31 Class ------- Default Mask: ---------------Network: ------------------- Broadcast: --------------------

Hosts: ----------------------through-----------------------

3. 172.30.77.5 Class ------- Default Mask: ---------------Network: ------------------- Broadcast: -------------------

Hosts: ----------------------through-----------------------


Who assigns the different addresses?

• Internet Assigned Numbers Authority (IANA), www.iana.net.• IANA is the master holder of the IP addresses• Registration companies, called Regional Internet Registries (RIRs),

manage the IP address space.

http://www.iana.net/


ISPs

• Tier 1 ISPs provides reliability and speed. • Tier 2 ISPs generally focus on business customers.• Tier 3 ISPs is the retail and home markets in a specific locale.


Overview of IP v6

• IPv6 is not merely a new Layer 3 protocol - it is a new protocol suite, ICMPv6, and new routing protocols. Large address space No need for NAT/PAT Improved Packet Handling through header simplification. QoS Mechanisms. Security


Overview of IP v6


ANDing- What is our network?

• The IPv4 host address is logically ANDed with its subnet mask to determine the network address to which the host is associated.


Basic Subnetting

• Subnetting: Creating multiple logical networks from a single address block.

• No. of subnets: 2n where n = the number of bits borrowed.

Dividing networks based on:1. geographic location2. Purposes3. ownership


Basic Subnetting – Borrowing 2 bits (4-Subnets)


Basic Subnetting – Borrowing 3 bits (8-Subnets)


VLSM – Subnetting a subnet

• was designed to maximize addressing efficiency.


Testing the local stack

• Ping: is a utility for testing IP connectivity between hosts.Uses ICMP.If the host Echo request, The destination responds with an

ICMP Echo Reply datagram.


Traceroute (tracert) – Testing the path

• tracert: utility that allows us to observe the path between source and destination.generates a list of hops that were successfully reached along

the path.• RTT (Round Trip Time): is the time a packet takes to reach the

remote host and for the response from the host to return.An asterisk (*) is used to indicate a lost packet.

• If TTL=0 thenThe router drops the packet and sends an ICMP Time Exceeded message addressed to the originating host.


ICMP v4

• ICMP is the messaging protocol for the TCP/IP suite. • ICMP provides control and error messages and is used by the

ping and traceroute utilities.• ICMP messages that may be sent include:

Host confirmationUnreachable Destination or Service

0 = net unreachable, 1 = host unreachable, 2 = protocol unreachable,

3 = port unreachableTime exceededRoute redirectionSource quench


Thank You..

Network Fundamentals: Ch6 - Addressing the Network IP v4

Technology

local network

multicast addresses

broadcast addresses

linklocal addresses

ip v4 network network

scoped addresses

experimental addresses

reserved link local