Why bother?

Application Layer

Presentation Layer

Session Layer

Transport Layer

Network Layer

Data Link Layer

Physical Layer

Layer Overlap!

Exam Summary




Now that you understand the OSI model what do you need to pass the OSI part of your exam?


Application layer

·         Telnet – A remote access application that transports your keystrokes to a remote device which interprets these as coming from its own keyboard.

·         FTP – File Transfer Protocol, more direct than sending files as e-mail attachments

·         SNMP – Simple Network Management Protocol, for monitoring and managing networks

·         SMTP – Simple Mail Transfer Protocol, used for e-mail programs such as MS Outlook and Eudora

·         POPv3 – Post Office Protocol version 3, an application that is used to fetch e-mail from mail servers, works together with SMTP

Presentation layer

·         ASCII – character coding

·         EBCDIC – character coding

·         JPEG – Joint Photographic Experts Group, used to compress colour images

·         MPEG – Moving Picture Experts Group, digital video compression standards and file formats

Session layer

·         RPC – Remote Procedure Call, a session layer protocol of the NFS suite of protocols

·         NetBIOS – Network Basic Input Output System a program that extends the original DOS with special functions for local area networks.

Transport layer

·         TCP – Transmission Control Protocol, provides connection-oriented, reliable data delivery functions for the TCP/IP protocol suite.

·         UDP – User Datagram Protocol, provides connectionless, unreliable data delivery functions for the TCP/IP protocol suite

·         SPX – Sequenced Packet Exchange, provides connection-oriented services for Novell NetWare networks.

Network layer

·         IP – Internet Protocol, provides logical, hierarchical addressing for TCP/IP - based protocols

·         IPX – Internetwork Packet Exchange, provides hierarchical addressing for Novell NetWare operating systems.

Data Link layer

·         Ethernet – Widely implemented LAN architecture developed by Xerox Corporation in co-operation with DEC and Intel

·         IEEE 802.2 – Logical Link control standards

·         IEEE 802.3 – MAC layer for LAN technology using CSMA/CD – based on Ethernet

·         IEEE 802.5 – MAC layer for token ring networks

·         HDLC – High-Level Data Link Control – encapsulates data on synchronous serial data links.

·         Frame relay – a packet-switching protocol for connecting devices across a WAN link

·         ATM – Asynchronous Transfer Mode, a high-speed, cell (fixed-size packet)-switching WAN technology

Physical Layer

·         EIA/TIA-232 – physical layer standards for cables and connectors defined by the Electronic Industries Association

·         V.35 – an International Telecommunication Union (ITU) standard for high-speed synchronous data exchange


Network layer

·         Router

Data link layer

·         Bridge, switch

Physical layer

·         Hub

For a full description of routing devices please see my other e-book “Networking Basics” which is available free on http://www.networkingbreak.com./



·         Transport layer – Segment

·         Network layer – Packet/Datagram

·         Data link layer – Frame

·         Physical layer – bits


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