1. IP Protocol - Introduction Dr. Farid Farahmand

2. Introduction TDM transport networks are not sufficient for data communications Low utilization TDM networks are being replaced by packet/frame/cell based data communication systems So the question is what are such communication systems and protocols? IP Networks Frame Relay Networks ATM Networks

3. Transport Protocol Classification Any communication system provides its services in two basic ways Dedicated lines (circuits) Shared lines (circuits) In packet/frame based technologies, shared resources are categorized as Connection oriented Multiple predefines virtual paths are established through the same physical link (highway system) The virtual path can be Permanent: logical circuit provisioned as the system us turned-up Switched: Logical circuit established upon request Connectionless No predefined path exists; routing takes place based on the source and destination nodes (airplane system)

4. Network Basics The backbone or core network Consists of switches, core routers, Gateway routers (maybe called Differently) Edge routers are used to be connected to the core network Data path Ingress Edge node Egress Edge node

5. Addressing - IP Protocol Provides proper addressing for different network elements Version 4 (IPv4) was the first working protocol IPv4 is almost unchanged since its inception in 1970s Processor speed has tripled Typical memory sizes have increased by 400 times Network BW has increased by 150,000 times There are hundreds of millions of routers on the NET!

6. Addressing - IP Protocol IPv4 Best-effort datagram delivery service addresses are 32 bits wide Its header is 20 bytes at minimum Uses doted-decimal notation (e.g. 43.23.43.56)

7. IP Header The IP datagram contains data and IP address The IP datagram is encapsulated in a frame with physical address The header changes as the frame goes from one network domain to the next IP Datagram Frame DataIP Address Frame Address

8. IPv4 Packet Format +0 - 34 - 78 - 1516 - 1819 - 31 0VersionHeader lengthType of ServiceTotal Length 32IdentificationFlagsFragment Offset 64Time to LiveProtocolHeader Checksum 96Source Address 128Destination Address 160Options 192 Data All numbers are in bits Header is 20 byte (20 x 8 bits)!

9. IP Packet Format - TTL TTL (time-to-live) refers to the number of router hops the IP packet is allowed before it must be discarded. Each router that receives a packet subtracts one from the count in the TTL field. When the count reaches zero, the router detecting it discards the packet and sends an Internet Control Message Protocol (ICMP) message back to the originating host.

10. Encapsulated IP Packet in Ethernet Frame MAC and Associated IP address IP Header with No Option Field Ethernet Frame Carrying IP Packet

11. Protocol Analyzer Display: 000000 00 C0 A0 51 24 00 C0 93 21 88 A7 08 00 45 08 0010 00 5A DC 28 00 00 FF 01 88 08 C0 99 B8 01 C0 99 0020 B8 01 2a B4 DD ….. Encapsulated IP Packet in Ethernet Frame Ethernet Frame Carrying IP Packet IP starting with 45 Hex indicates IPv4 with standard length of 20 bytes IP starting with 4F Hex indicates IPv4 with standard length of 60 bytes Remember: 2 4 =16; 45= 0100 0101= One Byte An Ethernet frame containing IP information has 08 00 in its type field 99 is one byte 1001 Example:

12. IP Addressing Two address types Physical address (the frame has the physical address) Embedded in the hardware (NIC, e.g., 00 00 11 00 11 33) Also called the Media Address Control (MAC) address Logical IP datagram contains the logical IP address To transport IP packets both physical and IP addresses must be known ARP (address resolution protocol) and RARP (reverse) address resolution protocol are used to convert MAC to IP address and vice versa Static address resolution Dynamic address resolution

13. IP Addressing A network address is divided into Netid and Hostid IP Address classification (number of hosts per network) ClassLeading bitsNetwork Address (Netid) Host Address (Hostid) Class A 0 7 bit (125) * 24 bit (16,777,151,750) Class B 10 14 bit (16,368) 16 bit (65,534) Class C 110 21 bit (2,096,896) 8 bit (254) Class D (multicast) 1110 Class E (reserved) 1111 * Some values are reserved!

14. Setting Up IP Addressing IP addresses are divided into the network portion and the host portion The subnet mask distinguishes the two portions

15. IP Addressing Common IP Classes ClassFirst numberSubnet maskNumber of networks Number of hosts Class A1 – 127255.0.0.0126>16,000,000 Class B128 – 191255.255.0.0> 16,000>65,000 Class C192 – 223255.255.255.0> 2,000,000254

16. IP Addressing Classification Network AddressHost Address Network Address Host Address Network Address Host Address Reserved for Internet research Multicast Address

17. Example of IP Addressing Q1: Determine the network address for the following IP addresses: 1- 84.42.58.11 (84 = 54 Hex = 0101 0100)  Netid=84.0.0.0  Class A  Hostid=0.42.58.11 2- 144.54.67.5 (144 = 90 Hex = 1001 0000)  Netid=144.62.0.0  Class B  Hostid=0.0.67.5 Q2: What type of IP address classification will a large organization with 1000 individual users in 150 dispersed buildings use?  Class B

18. TCP/IP Stack Protocol

19. Network Address Translation (NAT) NAT allows an IP address from one network to be translated into another address on an internal network You can also use NAT to translate a single IP address valid on the Internet into multiple internal addresses Useful if your ISP gives you a single IP address, yet you have multiple servers and users on the internal network

20. IPv6 Version 5 had too many bugs and was skipped! IETF (Internet Engineering Task Force) formulated version 6 Initially called IPng (IP – Next Generation) IPv6 features Provides larger address domain addresses are 128 bits wide ISPs can provide blocks of addresses to their customers Multiple separate headers are supported Handles audio and video; providing high quality paths Supports flow-labeling Provides authentication Supports unicast, multicast, anycast (one of may)

21. Is IPv6 Really Needed? VoIP works ok! Using NAT we can provide address extension We have enough addresses until 2022!  Maybe that is why the development is slow?

22. Current Internet Lacks applications that can access and process large complex data set Cannot provide high quality video and voice services Not to mention very wasteful!

23. Internet 2 Not for profit consortium Collaboration between the industry, academic and government institutions Objectives Develop new high-performance network for the global Internet Provide broader Internet Better infrastructure Supporting IPv6, QoS More services and technologies Distance learning, digital libraries, virtual laboratories, faster email and web browsing Tele-immersion

24. Internet 2 - Tele-immersion Tele-immersion is a technology to be implemented with Internet2 Users in different geographic locations to come together Recognizing the presence and movements of individuals and objects, tracking those individuals and images, and reconstructing them onto one stereo-immersive surface 3D reconstruction of motions in real-time Tele-immersion presents the greatest technological challenge for Internet2.

25. Homework – Due November 13 Read more about Internet 2 Which Universities in Connecticut are connected to Internet2? How much is it to subscribe to Internet2? How can we access Internet2? What is Internet2 being used for? What are its important applications? Name 2 Specific examples. How is video conferencing with Internet2 different from regular video conferencing? Is there a site to access/try Internet2? What types of technologies are involved in establishing Internet2, other than using IPv6? Can we have Internet2 using IPv4?

26. Sources Tomasi Text Book Comer Text book

27. Extra Credit