Computer network

Computer Network

Sritrusta Sukaridhoto

Computer Network – Sritrusta Sukaridhoto

Why Computer Network ???

Stand alone Computer ….

FOR WHAT ???

Computer Network – Sritrusta Sukaridhoto

Something interesting from Computer Network ??? Easiness No distance Mobility Efficient

Computer Network – Sritrusta Sukaridhoto

Network Administrator,…

Advantages Good salary Control other peoples Faster than others Relax

Disadvantages ERROR, then people

want to kill YOU !!!

Computer Network – Sritrusta Sukaridhoto

Study…

Basic network theoryOSI LayerNetwork devicesRoutingNetwork securityProgramming

Computer Network – Sritrusta Sukaridhoto

Study…

Network SkillOperating systemServer – ClientRouter, Switch, Cabling, etc (network devices)Hacking not CrackingCertificate

ExperienceTime can answer ???

Computer Network – Sritrusta Sukaridhoto

Open System Interconnection (OSI)

A model defines the stages or tasks of a protocol as it prepares to send data Open meaning standards

available to all. The model is devided into

seven distinct layers Each subsequent layer should

perform a well-defined function and the layer boundaries are designed to minimize the information flow across the interfaces

Computer Network – Sritrusta Sukaridhoto

OSI Model Layers

Application Layer Provides a user interface (examples: HTTP, SMTP) Includes file, print, database, app. Services

Presentation Layer Presents the data (example: JPEG) Includes encryption, compression and translation

services Session Layer

Keeps different applications data separate

Computer Network – Sritrusta Sukaridhoto

OSI Model Layers

Transport LayerProvides reliable deliveryPerforms error detection Includes end to end connection

Network LayerProvides logical addressing Routing layer

Computer Network – Sritrusta Sukaridhoto

OSI Model Layers

Data Link LayerCombines packets into bytes then into framesPerforms error detection (not correction)Provides Media access addressing (point-to-

point)Media Access Control and Data Link Control

Physical LayerMoves bits between devices

Computer Network – Sritrusta Sukaridhoto

Keys Layers of the OSI Model

Computer Network – Sritrusta Sukaridhoto

OSI Model and Protocols

Computer Network – Sritrusta Sukaridhoto

Network Devices

Wire Wireless

Computer Network – Sritrusta Sukaridhoto

Router, Switch, Hub, Modem, …

Computer Network – Sritrusta Sukaridhoto

TCP/IP

Computer Network – Sritrusta Sukaridhoto

TCP/IP

Computer Network – Sritrusta Sukaridhoto

Network Security

Firewall

Computer Network – Sritrusta Sukaridhoto

Operating Systems

Computer Network – Sritrusta Sukaridhoto

Computer Network – Sritrusta Sukaridhoto

Hacking NOT cracking

Computer Network – Sritrusta Sukaridhoto

Programming /* ** server.c -- a stream socket server demo */ #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <errno.h> #include <string.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <sys/wait.h> #include <signal.h> #define MYPORT 3490 // the port users will be connecting to #define BACKLOG 10 // how many pending connections queue will hold void sigchld_handler(int s) { while(wait(NULL) > 0); } int main(void) { int sockfd, new_fd; // listen on sock_fd, new connection on new_fd struct sockaddr_in my_addr; // my address information struct sockaddr_in their_addr; // connector's address information int sin_size; struct sigaction sa; int yes=1; if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) { perror("socket"); exit(1);

} if (setsockopt(sockfd,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) { perror("setsockopt"); exit(1); } my_addr.sin_family = AF_INET; // host byte order my_addr.sin_port = htons(MYPORT); // short, network byte order my_addr.sin_addr.s_addr = INADDR_ANY; // automatically fill with my IP memset(&(my_addr.sin_zero), '\0', 8); // zero the rest of the struct if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr)) == -1) { perror("bind"); exit(1); } if (listen(sockfd, BACKLOG) == -1) { perror("listen"); exit(1); } sa.sa_handler = sigchld_handler; // reap all dead processes sigemptyset(&sa.sa_mask); sa.sa_flags = SA_RESTART; if (sigaction(SIGCHLD, &sa, NULL) == -1) { perror("sigaction"); exit(1); } while(1) { // main accept() loop sin_size = sizeof(struct sockaddr_in); if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &sin_size)) == -1) { perror("accept"); continue; } printf("server: got connection from %s\n", inet_ntoa(their_addr.sin_addr)); if (!fork()) { // this is the child process close(sockfd); // child doesn't need the listener if (send(new_fd, "Hello, world!\n", 14, 0) == -1) perror("send"); close(new_fd); exit(0); } close(new_fd); // parent doesn't need this } return 0; }

Computer Network – Sritrusta Sukaridhoto

Server - Client

Computer Network – Sritrusta Sukaridhoto

Certificate

Computer Network – Sritrusta Sukaridhoto

Network topics

IPv6 Mobile-IP MPLS Network Security, VPN, IPSec Quality of Service VoIP Wireless Web-base application Encryption Decryption Streaming

Computer Network – Sritrusta Sukaridhoto

EEPIS Computer Network

Lab Jaringan KomputerKa. Lab: Sritrusta SukaridhotoGedung D4 lt. 3

UPT Jaringan KomputerKa. UPT: Dadet PNetwork Admin: Sukaridhoto, Hendri, Firman,

RezaGedung IT lt. 2

Computer Network – Sritrusta Sukaridhoto

Thank You…