TCP/IP Overview Basic Networking Concepts 09/14/11 Basic TCP/IP Networking 1
What is TCP/IP? TCP/IP is a name refers to an entire collection of data communication protocols: TCP: Transmission Control Protocol IP: Internet Protocol ICMP: Internet Control Message Protocol... 09/14/11 2
TCP/IP Features Open protocol standards Independence from specific physical network hardware Ethernet Token ring Dial-up line X.25 net A common addressing scheme Standardized high-level protocols 09/14/11 3
Topics of Discussion Data Communication Model TCP/IP Protocol Architecture TCP/IP Layers Major TCP/IP procotols in each Layer 09/14/11 4
Data Communication Model 09/14/11 5
TCP/IP Protocal Architecture 09/14/11 6
Application Layer The Application Layer is the level of the protocol hierarchy where user-accessed network processes reside. In TCP/IP, this refer to any network process that occurs above the Transport Layer. This includes all of the processes that users directly interact with, as well as other processes at this level that users are not necessarily aware of. 09/14/11 7
Transport Layer The Transport Layer guarantees that the receiver gets the data exactly as it was sent. In TCP/IP this function is performed by the Transmission Control Protocol (TCP). TCP/IP also offers a second Transport Layer service, User Datagram Protocol (UDP), that does not perform the end-toend reliability checks. 09/14/11 8
Network Layer The Network Layer manages connections across the network and isolates the upper layer protocols from the details of the underlying network. In TCP/IP, the Internet Protocol (IP) is used in the Network Layer 09/14/11 9
Data Link Layer The reliable delivery of data across the underlying physical network is handled by the Data Link Layer. TCP/IP rarely creates protocols in the Data Link Layer. Most RFCs that relate to the Data Link Layer discuss how IP can make use of existing data link protocols 09/14/11 10
Physical Layer The Physical Layer defines the characteristics of the hardware needed to carry the data transmission signal. Features such as voltage levels, and the number and location of interface pins, are defined in this layer. Examples:RS232C and V.35, IEEE 802.3. TCP/IP does not define physical standards - it makes use of existing standards. 09/14/11 11
TCP/IP Protocol Architecture 3 to 5 functional levels Data Encapsulation Headers Data 09/14/11 12
TCP/IP Data Encapsulation 09/14/11 13
Data Structures 09/14/11 14
Data Link and Physical Layer The lowest layer Protocols in this layer provide the means for networking device to deliver data to the other devices on a directly attached network. Protocols in this layer are hidden to the users IP (logical network) addresses are converted into physical (network) addresses e.g. ARP address resolution protocol 09/14/11 15
Network Layer Internet Protocol (IP) IPv4 and Ipv6 (connectionless protocol) Defines the datagram basic unit of transmission Defines the Internet addressing scheme Moves data between Network access layer and the Transport layer Routes datagrams to remote hosts Performs fragmentation and re-assembly of datagrams 09/14/11 16
IP Datagram Format 09/14/11 17
Routing 09/14/11 18
Network Layer ICMP Internet Control Message Protocol provides: Flow control unreachable destinations detection Routes redirection Remote hosts status checking 09/14/11 19
Transport Layer Transmission Control Protocol (TCP): Reliable data delivery with positive acknowledgment with retransmission Connection-oriented Three-way handshake User Datagram Protocol (UDP) Minimum protocol overhead (unreliable) Connectionless 09/14/11 20
Application Layer Application Protocols: HTTP Hypertext Transfer Protocol SMTP Simple Mail Transfer Protocol DNS Domain Name Service FTP File Transfer Protocol Telnet Network Terminal Protocol NFS Network File System NIS Network Information System 09/14/11 21