Contrast Simplex, Half-Duplex, and Full-Duplex connections
Simplex is one-way, Half-Duplex takes turns sending and receiving, Full-Duplex sends and receives simultaneously
Define and describe the OSI Model
The Open Systems Interconnection Model, is a set of rules that explains how different computer systems communicate over a network
How many layers are in the OSI Model?
7
Describe the 1st layer of the OSI Model
The physical layer is responsible for the actual physical connection between devices, information is transported in bits, common devices are hubs, modems, repeaters, and cables
What are the 4 functions of Layer 1?
Bit Synchronization (Clock setting), Bit Rate Control (Speed setting), Topology (How devices/nodes are arranged), Transmission Mode (How data flows)
Describe the 2nd layer of the OSI Model
The Data Link Layer (DLL) is responsible for the node-to-node delivery of the the information, information is transported in frames, common devices are switches and bridges
What are the 5 functions of Layer 2?
Framing (Organizing bits), Physical Addressing (Adding MAC address in header), Error Control (Detect and retransmit errors), Flow Control (Bit Rate Synchronization), Access Control (Determining which device uses the channel at any given time)
Describe the 3rd layer of the OSI Model
The Network Layer is responsible for the transmission of data from one host to another located in different networks, information is transported in packets, common devices are routers and switches
What are the 2 functions of Layer 3?
Packet Routing (Optimizing the path), Defining the IP Addresses
Describe the 4th layer of the OSI Model
The Transport Layer facilitates sharing resources between the Network and Application layers, information is transported in segments, common protocols are TCP, UDP, NetBIOS, and PPTP
What are the 5 functions of Layer 4?
Segmentation (Breaking the message into smaller units), Flow and Error Control, Assigning Port Numbers, Port Forwarding, Reassembly (Desegmentation)
Describe the 5th layer of the OSI Model
The Session Layer is responsible for the establishment, management, and termination of connections (sessions) between devices
What are the 4 functions of Layer 5?
Provides authentication and security to NetBIOS and PPTP, Connection Management, Implanting Synchronization Points, Dialog Controller (Facilitating communication in half or full-duplex)
Describe the 6th layer of the OSI Model
The Presentation/Translation Layer translates the data from the Application layer into a transmittable form, common protocols are JPEG, MPEG, GIF, TSL/SSL
What are the 3 functions of Layer 6?
Translation (Converting input data into a transmittable format), Encryption/Decryption, Compression
Describe the 7th layer of the OSI Model
The Application Layer allows the user to interface with the network through an application and produce data for transmission, common protocols are SMTP, FTP, DNS
What are 4 major functions of Layer 7?
Remote Login, Remote File Access, Mail Services, Directory Services