CIS 471 : sheet.pdf
1 Mar 2014
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Document Summary
Application - identifying and establishing the availability of intended communication partner and whether there are sufficient resources. Session - setting up, managing and tearing down sessions. Transport - provides end-to-end transport services - establishes logical connections between hosts. Connection- oriented or connectionless data transfer. t e k c a p e m a r f s t i b. Network - manages logical addressing and path determination. Data link - provides physical transmission of data, handles error notification, flow control and network topology. Split into two sub layers (llc and mac) Physical - specifies electrical, mechanical, procedural and functional requirements for activating, maintaining and deactivating a physical link. Ftp - tcp file transfer service port 20-21. Tftp - udp file transfer port 69. Smtp - send email service port 25. Dhcp assigns ip addresses to hosts ports 67 and 68. Dns resolves fqdns to ip addresses port 53. Tcp - connection-oriented protocol, provides reliable connections (acknowledgments, flow control, windowing)
