1 Module 01 InterNetwork Overview Chapter 05 Fundamentals of IP 2 Table of Content 1 Typical Features of OSI Layer 3 2 IP Addressing Fundamentals 3 Network Layer Utilities 3 1. Typical Features of OSI Layer 3 4 Routing overview  Routing is an OSI Layer 3 function.  Routing is the process of finding the most efficient path from one device to another.  The primary device that performs the routing process is the router.  Routers must maintain routing tables and make sure other routers know of changes in the network topology.  The router switches the packets to the appropriate interface, adds the necessary framing information for the interface, and then transmits the frame. 5 Routing Logic: PC1 Sending to PC2 Token Ring 10.1.1.1 PC1 R1 R2 R3 PC2 168.1.1.1 Destination Is in another Group; Send to Nearby Router. My Route to that Group Is Out Serial Link. My Route to that Group Is Out Frame Relay. Send Directly to PC2 6 Network Layer and Data Link Layer Encapsulation Frame-Relay Token Ring 10.1.1.1 PC1 R1 R2 R3 PC2 168.1.1.1 Encapsulate IP Packet in Ethernet Extract IP Packet and Encapsulate in HDLC Extract IP Packet, and Encapsulate in Frame Relay Extract IP Packet, and Encapsulate in Token Ring TR IP Packet Eth IP packet HDLC IP packet FR IP packet TR IP packet 7 Routing Protocol • Routing protocols allow routers to choose the best path for data from source to destination. • Functions includes the following: – Provides processes for sharing route information. – Allows routers to communicate with other routers to update and maintain the routing tables 8 IP Routing and Routing Protocols Frame-Relay 150.150.3.0 Token Ring 150.150.1.10 PC1 R1 R2 R3 PC2 150.150.4.10 Subnets Out interface Next hop IP 150.150.4.0 Serial 0 150.150.2.7 Subnets Out interface Next hop IP 150.150.4.0 Serial1 150.150.3.1 Subnets Out interface Next hop IP 150.150.4.0 Ethernet 0 N/A 150.150.2.0 .7 .1 .4 Default router: 150.150.1.4 9 2. IP Addressing Fundamentals 1 0 IP address classes  To accommodate different size networks and aid in classifying these networks, IP addresses are divided into groups called classes. This is known as classful addressing.  Different class addresses reserve different amounts of bits for the Network and Host portions of the address Class A Network Host Octet 1 2 3 4 Class B Network Host Octet 1 2 3 4 Class C Network Host Octet 1 2 3 4 [...]... Subnetting: Example Class C Network address: 192.168.10.0 11000000 N 1010 10000 N 00 0010 10 00000000 N H 11000000 1010 10000 00 0010 10 N N N 00000000 sN H Class B Network address: 132.10.0.0 100 0010 0 N 100 0010 0 N 00 0010 10 N 00000000 N H 00 0010 10 N 00000000 00000000 sN H 00000000 H Class A Network address: 10.0.0.0 00 0010 10 N 00000000 N 00 0010 10 00000000 N sN 00000000 N 00000000 sN H 00000000 H 00000000... Default subnet Mask Network address 11111111 11000000 11111111 11111111 1010 10000 00 0010 10 00000000 00000000 Class A Network address: 10.0.160.13/255.255.240.0 (or /20) IP Address 00 0010 10 N 00000000 sN 1010 0000 sN H 00 0011 01 H AND operation Subnet Mask 11111111 11111111 11111111 00000000 Network address 00 0010 10 00000000 1010 0000 00000000 2 3 Network Layer Utilities 2 Address Resolution Protocol... MAC MAC IP This is my MAC Addr 197.15.22.33 197.15.22.44 197.15.22.126 02.06.8C .01. 02.03 00.00.A2 .05. 09.89 00 .05. 5D.88.94.F2 A B C 02.06.8C .01. 02.03 00 .05. 5D.88.94.F2 IP 197.15.22.126 197.15.22.33 3 ARP operation: Caching ARP Table: 00 .05. 5D.88.94.F2 – 197.15.22.126 MAC MAC IP IP 00 .05. 5D.88.94.F2 02.06.8C .01. 02.03 197.15.22.33 197.15.22.126 Data 197.15.22.33 197.15.22.44 197.15.22.126 02.06.8C .01. 02.03... IP 02.06.8C .01. 02.03 197.15.22.33 197.15.22.126 What is your MAC Addr? 197.15.22.33 197.15.22.44 197.15.22.126 02.06.8C .01. 02.03 00.00.A2 .05. 09.89 00 .05. 5D.88.94.F2 A B C 3 ARP operation: Checking MAC ff.ff.ff.ff.ff.ff MAC IP IP 02.06.8C .01. 02.03 197.15.22.33 197.15.22.126 What is your MAC Addr? is a t IP h y T m 197.15.22.33 197.15.22.44 197.15.22.35 02.06.8C .01. 02.03 00.00.A2 .05. 09.89 00 .05. 5D.88.94.F2... router the information to determines which part of an IP address is the network field and which part is the host field  32 bits long, divided into four octets  Network and Subnet portions all 1’s  Host portions all 0’s 2 Subnet mask: Example Class C Network address: 192.168.10.100/255.255.255.0 (or /24) IP Address 11000000 N 1010 10000 N 00 0010 10 011 0010 0 N H AND operation Default subnet Mask Network... Class B 1 IP address classes: Class B  The first 2 bits of a Class B address is always 10  The first two octets to identify the network part of the address  Possible network address from 128.0.0.0 to 191.255.0.0 (2 14)  The remaining two octets can be used for the host portion of the address  Class B network have up to 65.534 possible IP addresses (2 16 -2 ) 1 IP address classes: Class C 1 IP address.. .IP address classes: Class A 1 IP address classes: Class A  The first bit of a Class A address is always 0  The first 8 bits to identify the network part of the address  Possible network address from 1.0.0.0 to 126.0.0.0  The remaining three octets can be used for the host portion of the address  Each class A network have up to 16,777,214 possible IP addresses( 22 4-2 ) 1 IP address classes:... Class C  The first 3 bits of a Class C address is always 110  The first three octets to identify the network part of the address  Possible network address from 192.0.0.0 to 223.255.255.0  The remaining last octet can be used for the host portion of the address  Class C network have up to 254 possible IP addresses (2 8 -2 ) 1 IP address classes: Summary       1.0.0.0 - 126.0.0.0 : Class A 127.0.0.0... both the IP addresses and the MAC addresses of the destination devices  When they try to communicate with devices whose IP addresses they know, they must determine the MAC addresses  ARP enables a computer to find the MAC address of the computer that is associated with an IP address 2 Address resolution protocol 2 ARP table in host AM R 2 ARP operation: ARP request MAC ff.ff.ff.ff.ff.ff MAC IP IP 02.06.8C .01. 02.03...     1.0.0.0 - 126.0.0.0 : Class A 127.0.0.0 : Loopback network 128.0.0.0 - 191.255.0.0 : Class B 192.0.0.0 - 223.255.255.0 : Class C 224.0.0.0 < 240.0.0.0 : Class D, multicast >= 240.0.0.0 : Class E, reserved 1 How IP Addresses Are Grouped Together  All IP addresses in the same group must not be separated by a router  IP addresses separated by a router must be in different groups 1 Why we need . 1 Module 01 InterNetwork Overview Chapter 05 Fundamentals of IP 2 Table of Content 1 Typical Features of OSI Layer 3 2 IP Addressing Fundamentals 3 Network Layer Utilities 3 1 portion of the address.  Each class A network have up to 16,777,214 possible IP addresses( 2 24 -2 ) 1 3 IP address classes: Class B 1 4 IP address classes: Class B  The first 2 bits of a Class. possible IP addresses (2 8 -2 ) . 1 7 IP address classes: Summary  1.0.0.0 - 126.0.0.0 : Class A.  127.0.0.0 : Loopback network.  128.0.0.0 - 191.255.0.0 : Class B.  192.0.0.0 - 223.255.255.0