TCP/IP Networks Dr. Miled M. Tezeghdanti October 7, 2011 Dr. Miled - PDF document

TCP/IP Networks Dr. Miled M. Tezeghdanti October 7, 2011 Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 1 / 94 Outline TCP/IP IP ARP ICMP TCP/UDP Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 2 / 94

History ARPANET 1969: 4 workstations, Backbone (50 Kbps) ARPA ”Advanced Research Project Agency”, DoD (1957) DARPA ”The Defense Advanced Research Project Agency” (1973) NCP ”Network Control Protocol” TCP/IP 1973 Vint Cerf (Stanford), Bob Khan (DARPA) 1974, first use of the ”Internet” word in their paper ”Transmission Control Protocol” Use of TCP/IP in ARPANET in 1976 ARPANET (1984) MILNET, ARPANET(Internet) Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 3 / 94 Internet Organizations IAB : Internet Architecture Broad (1983) Design, Engineering, and Management of Internet IETF : Internet Engineering Task Force (1986) Technical Development of Internet Working Groups Example: ospf (Open Shortest Path First IGP) Managed by IESG: Internet Engineering Steering Group IRTF : Internet Research Task Force (1986) Research and long-term development of Internet Research Groups Managed by IRSG: Internet Research Steering Group Example: Routing Research Group Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 4 / 94

Internet Organizations ISOC: Internet Society (1992) Internet Promotion Contains IAB, IETF, and IRTF W3C: World Wide Web Consortium (1994) Tim Berners-Lee CERN DARPA, European Commission ICANN: The Internet Corporation for Assigned Names and Numbers (1998) Successor of IANA: Internet Assigned Numbers Authority It is the highest international authority for all questions related to domain names, addresses, and protocols. Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 5 / 94 Internet Organizations IAB IESG IRSG IETF IRTF ISOC Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 6 / 94

Standards RFC : Request For Comments RFC 2328 RFC Internet Draft RFC Prototype Experimental Informational Historic Standard Proposed Standard 1 Draft Standard 2 Internet Standard 3 Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 7 / 94 TCP/IP Model Application Presentation Application Session Transport Transport Network Network Data-Link Data-Link Physical Physical TCP/IP Model OSI Model Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 8 / 94

Physical Layer Layer 1 of OSI Model It provides services to the Data Link Layer Physical Layer Functions Definition of Hardware Specifications Cables, Connectors, Transceivers, Network Interface Cards (NIC), ... Encoding, Modulation, and Signaling Data Transmission and Reception Example of Physical layer standards X.21 Defines physical interface between DTE and DCE DTE (Data Terminal Equipment) DCE (Data Circuit Equipment) Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 9 / 94 Data Link Layer Layer 2 of OSI Model It uses services of the Physical layer It provides services to the Network Layer It performs following functions: Framing Transport of Network layer data using frames Error Control Error Detection and Error Correction Flow Control Traffic regulation between sender and receiver in order to meet the receiver requirements Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 10 / 94

Network Layer Layer 3 of OSI Model It uses Data-Link layer services Its provides services to the Transport Layer It performs following functions: Addressing Logical Addressing Routing Computation of routes between different nodes Congestion Control Traffic regulation in order to meet the network requirements Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 11 / 94 Transport Layer Layer 4 of OSI model It uses Network Layer services It provides services to the Session Layer It performs following functions: Multiplexing Segmentation and Reassembly Flow Control (at the process level) Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 12 / 94

Session Layer Layer 5 of OSI model It uses Transport layer services It provides services to the Presentation Layer It performs following functions: Synchronization Dialogue Management Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 13 / 94 Presentation Layer Layer 6 of OSI Model It uses Session layer services It provides services to the Application Layer It performs following functions: Information Encoding (Translation) Compression/Decompression Encryption/Decryption Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 14 / 94

Application Layer Layer 7 of OSI model It uses Presentation layer services It provides services to the communicating processes It allows to application processes to access OSI environment and offers to the user basic services such as file transfer and specific services such as database access FTAM VT Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 15 / 94 TCP/IP Stack FTP TELNET SMTP HTTP SNMP Application BGP RIP TCP UDP Transport ICMP OSPF IP ARP Network Data-Link Physical Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 16 / 94

IP Protocol Internet Protocol RFC 791 Network Layer Interconnection of networks Ethernet Token Bus Token Ring Hardware is hidden by the Network layer some exceptions like MTU: Maximum Transmission Unit Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 17 / 94 Functions provided by the IP layer Addressing Routing Forwarding Fragmentation and Reassembly Error Notification Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 18 / 94

IP Sending and Receiving of packets No retransmissions IP does not provide a reliable forwarding service Packets may be: lost dropped duplicated delayed corrupted delivered out of order Best effort service Network does his best effort to forward packets Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 19 / 94 IP Addressing An IP address is represented on 32 bits (4 bytes) Every equipment has an IP address which identifies it in a unique manner on the network IP Address Representation Dotted-Decimal Representation 4 decimal numbers separated by decimal point Value between 0 and 255 for each number Example 10000011000100011100000100000001 10000011.00010001.11000001.00000001 131.17.193.1 Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 20 / 94

Addressing With 32 bits, we can have 2 32 different IP addresses Addressing space is divided in many classes An address is divided in two parts The first part represents the address of the network connected to the host (workstation) The second part represents the address of the host (workstation) on the network Hosts connected to the same network have the same network address (first part of the address is the same for all these hosts) Mask 32 bits Allows the distinction between the network part and the host part of the address (1 if the bit belongs to the net-id, 0 otherwise) Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 21 / 94 Addressing 0XXXXXXX . XXXXXXXX . XXXXXXXX . XXXXXXXX Class A 10XXXXXX . XXXXXXXX . XXXXXXXX . XXXXXXXX Class B 110XXXXX . XXXXXXXX . XXXXXXXX . XXXXXXXX Class C 1110XXXX . XXXXXXXX . XXXXXXXX . XXXXXXXX Class D 11110XXX . XXXXXXXX . XXXXXXXX . XXXXXXXX Class E Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 22 / 94

Addressing: Class A 0XXXXXXX . XXXXXXXX . XXXXXXXX . XXXXXXXX Class A Net-id Host-id Net-id: 8 bits 2 7 − 2 = 126 class A networks 1 . . . 126 (0 and 127 reserved) Host-id: 24 bits 2 24 − 2 = 16777214 hosts Example: 12.5.2.3 Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 23 / 94 Addressing: Class B 10XXXXXX . XXXXXXXX . XXXXXXXX . XXXXXXXX Class B Net-id Host-id Net-id: 16 bits 2 14 = 16384 class B networks 128 . . . 191 Host-id: 16 bits 2 16 − 2 = 65534 hosts Example: 130.20.6.1 Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 24 / 94

Addressing: Class C 110XXXXX . XXXXXXXX . XXXXXXXX . XXXXXXXX Class C Net-id Host-id Net-id: 24 bits 2 21 = 2097152 class C networks 192 . . . 223 Host-id: 16 bits 2 8 − 2 = 254 hosts Example: 195.16.26.17 Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 25 / 94 Private Addressing Private Address: is an IP address that cannot be used to interconnect a host to Internet Private addresses: Class A 10.0.0.0 - 10.255.255.255 Class B 172.16.0.0 - 172.31.255.255 Class C 192.168.0.0 - 192.168.255.255 Examples 10.1.3.2 172.16.8.17 192.168.20.39 Dr. Miled M. Tezeghdanti () TCP/IP Networks October 7, 2011 26 / 94