November 29, 2004 Prof. Paul Lin 1 CPET Internetworking, Addressing, and Routing Paul I-Hai Lin, Professor Electrical and Computer Engineering Technology Purdue University, Fort Wayne Campus

November 29, 2004 Prof. Paul Lin 2 Network Layer - an Overview Getting data packets from the source all the way to the destination Getting data packets from the source all the way to the destination Dealing with end-to-end transmission Dealing with end-to-end transmission Need to know Need to know Topology of the communication subnet (routers)Topology of the communication subnet (routers) Chose paths (routing algorithms)Chose paths (routing algorithms)

November 29, 2004 Prof. Paul Lin 3 Position of Network Layer Courtesy - From Fig. 1, Page 467, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 4 Network Layer Duties Courtesy - From Fig. 2, Page 468, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 5 Network Layer Topics of Discussion Network Layer Design Issue Network Layer Design Issue Services to the TCP LayerServices to the TCP Layer Connectionless Services (Datagram) Connectionless Services (Datagram) Connection-Oriented Services (Virtual Circuit) Connection-Oriented Services (Virtual Circuit) SubnetsSubnets Internetworking Internetworking Addressing Addressing Routing Routing

November 29, 2004 Prof. Paul Lin 6 Internetworks Courtesy - From Fig. 19.1, Page 471, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Host A -> Host D 4 LANS, 1 WAN S1, S2, S3: Switch or Router f1, f2: Interface Three links: S1 -> S2 -> s3

November 29, 2004 Prof. Paul Lin 7 Links in an Internetwork Courtesy - From Fig. 19.2, Page 472, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 8 Network Layer in an Internetwork Courtesy - From Fig Page 473, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 9 Network Layer at the Source Courtesy - From Fig Page 473, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Creating Source and Destination Address, Fragmentation

November 29, 2004 Prof. Paul Lin 10 Network Layer at Router or Switch Courtesy - From Fig Page 474, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Routing Table, Fragmentation

November 29, 2004 Prof. Paul Lin 11 Network Layer at Destination Courtesy - From Fig. 196 Page 475, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Corrupted packet, Fragments

November 29, 2004 Prof. Paul Lin 12 Quality of Service Requirements From Fig. 5-30, Page 397, Computer Networks, 4 th edition, Andrew S. Tanenbaum, Prentice Hall

November 29, 2004 Prof. Paul Lin 13 Packet-Switched Network - Internet Courtesy - From Fig. 196 Page 475, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Packets – Variable Length Data Blocks; Node to Node Delivery Virtual Circuit – WAN, Frame Relaying, ATM applications, call setup a single route

November 29, 2004 Prof. Paul Lin 14 Packet-Switched Network - Internet Courtesy - From Fig. 196 Page 475, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Datagram Approach – no fixed path, routing, out of order Packets == Datagrams

November 29, 2004 Prof. Paul Lin 15 Addressing Internet Address – IP Address Classful addressing – original architecture Class A, B, C, D, and E Classless addressing – mid 1990s IPv4 32-bit binary number Dotted-Decimal Notation IPv bit

November 29, 2004 Prof. Paul Lin 16 Addressing – IPV4 Courtesy - From Fig Page 479, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Network ID, Host ID Class A – 128 blocks (First Byte), 16,777,216 hosts Class B – 16,384 blocks (First & Second Byte), hosts Class C – 2,097,152 blocks (First, Second, Third byte), 256 hosts Class D – 1 block, Multicasting

November 29, 2004 Prof. Paul Lin 17 Finding the Class Courtesy - From Fig Page 480, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 18 Netid and Hostid Courtesy - From Fig Page 481, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 19 Classes and Blocks - Netid 73 Courtesy - From Fig Page 482, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill 128 Blocks; 16,777,216 Hosts

November 29, 2004 Prof. Paul Lin 20 Blocks in Class B Network Courtesy - From Fig Page 483, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Blocks; Hosts

November 29, 2004 Prof. Paul Lin 21 Blocks in Class C Network Courtesy - From Fig Page 484, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill 2,097,152 Blocks; 255 Hosts

November 29, 2004 Prof. Paul Lin 22 Network Address Courtesy - From Fig Page 484, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill An address defines a network with all host-id = 0

November 29, 2004 Prof. Paul Lin 23 Sample Internet Courtesy - From Fig Page 486, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 24 Subnetting Courtesy - From Fig Page 487, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Class B – 1 block, hosts (16-bit) Subnets 2 sub-blocks (1-bit), hosts (15-bit) 4 sub-blocks (2-bit), hosts (14-bit) … 128 sub-blocks (7-bit), 512 host (9-bit)

November 29, 2004 Prof. Paul Lin 25 Subnetting – 3 Level Hierarchy Courtesy - From Fig Page 487, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Three levels: Site, Subnet, Host

November 29, 2004 Prof. Paul Lin 26 A Network With and Without Subnetting Courtesy - From Fig Page 488, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 27 Masks Courtesy - From Table 19.1 Page 489, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Class In Binary In Dotted- Decimal Using Slash A /8 B /16 C /24

November 29, 2004 Prof. Paul Lin 28 Supernetting An organization can combine several class C block to form a larger range of addresses

November 29, 2004 Prof. Paul Lin 29 Classless Addressing Variable-Length Block (2, 4, 128, etc) Mask Finding the Network Address Subnetting CIDR (Classes InterDomain Routing)

November 29, 2004 Prof. Paul Lin 30 Dynamic Address Configuration DHCP (Dynamic Host Configuration Protocol) Database 1 (static) - Physical addresses to IP addresses Database 2 (dynamic) – Available IP, Lease Time

November 29, 2004 Prof. Paul Lin 31 Network Address Translation Courtesy – Table 19.2 Page 494, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill RangeTotal to to to Internally, a large set of addresses Externally, one address, or a small set of addresses

November 29, 2004 Prof. Paul Lin 32 A NAT Example Courtesy – Fig Page 495, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Private address: to NAT Router address:

November 29, 2004 Prof. Paul Lin 33 Address Translation Courtesy – Fig Page 495, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Private address: to NAT Router address:

November 29, 2004 Prof. Paul Lin 34 Address Translation (cont.) Courtesy – Fig Page 495, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 35 Translation Table Courtesy – Table 19.3 Page 497, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill Private Address Private Port External Address External Port Transport Protocol TCP TCP

November 29, 2004 Prof. Paul Lin 36 Routing Techniques Routing Tables Next-Hop Routing Network-Specific Routing Host-Specific Routing Default Routing

November 29, 2004 Prof. Paul Lin 37 Translation Table Courtesy – Fig Page 496, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 38 Next-Hop Routing Courtesy – Fig Page 498, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 39 Network-Specific Routing Courtesy – Fig Page 498, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 40 Host-Specific Routing Courtesy – Fig Page 499, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 41 Default Routing Courtesy – Fig Page 500, Data Communications and Networks, 3rd edition, Forouzan, McGrawHill

November 29, 2004 Prof. Paul Lin 42 More on Routing Static vs Dynamic Static Routing Table Dynamic Routing Table and Protocols RIP – Routing Information Protocol OSPF – Open Shortest Path First BGF – Border Gateway Protocol Routing Tables For Classful Addressing For Classless Addressing (CIDR)