11/10/2010 Ing. Manuel Benites 7 Multiplexing a. Frequency division (FDM ) b. Time division (TDM) c. Applications and hierarchies 8 El Modelo OSI a. Architecture and layers of the model b. Functions and interconnection of layers 1 11/10/2010 7 Multiplexing Multiplexing categories 7 Multiplexing a. Frequency division (FDM) 2 11/10/2010 7 Multiplexing a. Frequency division (FDM ) 7 Multiplexing a. Frequency division (FDM) FDM is a multiplexing technique that combines analog signals. 3 11/10/2010 7 Multiplexing a. Frequency division (FDM) FDM Process 7 Multiplexing a. Frequency division (FDM) Example of FDM multiplexing 4 11/10/2010 7 Multiplexing b. Time division (TDM) 7 Multiplexing b. Time division (TDM) TDM is a digital multiplexing technique for combining several low‐speed channels into one high‐capacity channel. 5 11/10/2010 7 Multiplexing b. Time division (TDM) Synchronous TDM multiplexing Figure 3-37 7 Multiplexing b. Time division (TDM) Syypgnchronous TDM multiplexing 6 11/10/2010 7 Multiplexing b. Time division (TDM) In the synchronous TDM, the data rate of the link is n times faster, and the unit of duration is n times shorter. Figure 3-39 7 Multiplexing b. Time division (TDM) Asynchronous TDM 7 11/10/2010 7 Multiplexing c. Applications and hierarchies 7 Multiplexing c. Applications and hierarchies Analog hierarchy 8 11/10/2010 8 The OSI Model a. Architecture and layers of the model b. Functions and interconnection of layers 8 The OSI Model a. Architecture and layers of the model Established in 1947, the International Standards Organization (OSI) is a multinational organization concerned with attaining agreement on international standardsstandards.. An OSI standard tha t covers all aspects of network communications is the Open Systems Interconnection modelmodel..ItItwas the first model introduced in the 19701970ss.. 9 11/10/2010 8 The OSI model a. Architecture and layers of the model The OSI seven‐layer model 8 The OSI model a. Architecture and layers of the model ISO model –Interaction between layers 10 11/10/2010 8 The OSI model b. Functions and interconnection of layers An exchange using the ISO model 8 The OSI model b. Functions and interconnectin of layers Physical layer 11 11/10/2010 8 The OSI model b. Functions and interconnection of layers The physical layer is responsible for the movement of individual bits from one node (hop) to the next 8 The OSI model b. Functions and interconnection of layers Data link layer 12 11/10/2010 8 The OSI model b. Functions and interconnection of layers The data link layer is responsible for moving frames from one hop to the next. 8 The OSI model b. Functions and interconnection of layers Hop-to-hop delivery 13 11/10/2010 8 The OSI model b. Functions and interconnection of layers Network layer 8 The OSI model b. Functions and interconnection of levels The network layer is responsible for delivering individual packets from the source host to the destination host. 14 11/10/2010 8 The OSI model b. Functions and interconnection of layers Source – destination delivery 8 The OSI Model b. Functions and interconnection of layers Transport layer 15 11/10/2010 8 The OSI model b. Functions and interconnection of layers The transport layer is responsible for delivering a message from one process to another. 8 The OSI model b. Functions and interconnection of layers Reliability in message delivery Process - process 16 11/10/2010 8 The OSI model b. Functions and interconnection of layers Session layer 8 The OSI model b. Functions and interconnection of layers The session layer is responsible for dialogue control and syncronization. 17 11/10/2010 8 The OSI model b. Functions and interconnection of layers Presentation layer 8 The OSI model b. Functions and interconnection of layers The presentation layer is responsible for translation, compression and encryption 18 11/10/2010 8 The OSI model b. Functions and interconnection of layers Application layer 8 The OSI model b. Functions and interconnection of layers The application layer is responsible for the provision of services to the user. 19 11/10/2010 8 The OSI model b. Functions and interconnection of layers Summary of layers 20.