310 likes | 335 Views
Layered Protocol. Types of Networks by Logical Connectivity. Peer to Peer and Client-Server Peer-to-peer Networks Every computer can communicate directly with every other computer By default, no computer has more authority than another
E N D
Types of Networks by Logical Connectivity • Peer to Peer and Client-Server • Peer-to-peer Networks • Every computer can communicate directly with every other computer • By default, no computer has more authority than another • Every computer is capable of sending and receiving information to and from every other computer
Peer-to-peer Networks Figure 1-1: Resource sharing on a simple peer-to-peer network
Type of Networks • Client/Server • Server: central computer used to facilitate communication and resource sharing between other computers on the network (called clients) • Client/server network: uses a server to enable clients to share data, data storage space, and devices • To function as a server, a computer must be running a network operating system (NOS)
Client/Server Networks (continued) Figure 1-2: Resource sharing on a client/server network
Client/Server Networks • Advantages of using client/server networks over peer-to-peer networks: • User logon accounts and passwords can be assigned in one place • Access to multiple shared resources can be centrally granted to a single user or groups of users • Problems can be tracked, diagnosed, and often fixed from one location
Client/Server Networks • Advantages of using client/server networks over peer-to-peer networks (continued): • Servers are optimized to handle heavy processing loads and dedicated to handling requests from clients, enabling faster response time • Because of their efficient processing and larger disk storage, servers can connect more than a handful of computers on a network
Network Classification by Area • PAN (Personal Area Network) • Local area network (LAN): confined to a relatively small space, such as a building or an office • Metropolitan area network (MAN): larger than a LAN; connects clients and servers from multiple buildings • Wide area network (WAN): connects two or more geographically distinct LANs or MANs
LANs, MANs, and WANs Figure 1-4: A simple WAN
Communication is successful when the message already received and confirmed May have to agree on the language used Agree on the method used What is Communication
Protocols • Driving Force: need for different proprietary networking system to communicate • Protocol: set of rules for acceptable behaviour to enable communication • Specifically: • the set of rules used by communicating parties for that communication to be successful • Suite of protocols cover all required behaviour • Mostly implemented in software • Complexity demands that protocols are ‘layered’
ISO/OSI Reference Model • ISO in 1984 • Open Systems Interconnect (OSI) • A design guideline for network layering • Abstract layers provide different services • Defines 7 layers of service • Each layer provides service to adjacent layers • Each layer communicates with same layer in remote machine.
Application Layer Application Layer Presentation Layer Presentation Layer Session Layer Session Layer Transport Layer Transport Layer Network Layer Network Layer Link Layer Link Layer Physical Layer Physical Layer OSI Reference Model
FTP – File Transfer Protocol HTTP – Hypertext Transfer Protocol WAP – Wireless Application Protocol SMTP – Simple Mail Transfer Protocol 5-7 TCP UDP 4 IP 3 1-2 e.g. IEEE 802.x
Packet Tracer • Example of packet data unit (PDU) in layered network
Movie • GoodWarriors
Quiz • What are the differences between • Circuit switching and packet switching • Connection oriented and connectionless oriented • Protocols • What are they? • Why do we layer protocols? • ISO/OSI – 7 layer reference model • How does the OSI abstract services? • How does TCP/IP stack relate to OSI?
Topik • IM & SIP protocol • Dhcp & e-mail protocol • p2p protocol • ipv6 & packettracer • Vlan • rip & ospf • Ns2, contoh aplikasi • omnet++, contoh aplikasi