Pengantar Teknologi Informasi

1. Pengantar Teknologi Informasi Komunikasi Data dan Jaringan Komputer

2. Sistem Komunikasi Data • Melibatkan minimal 2 simpul • Simpul bisa berupa komputer maupun peralatan lain • Simpul berperan sebagai pengirim dan/atau penerima data • Dihubungkan oleh media transmisi • Data yg ditransmisikan berupa isyarat listrik

3. Gangguan Komunikasi Data • Data yg sampai kepada penerima bisa tidak sama dg yg disampaikan pengirim • Penyebab Utama • Atenuasi • Pelemahan sinyal akibat jarak • Distorsi Tunda • Pengaruh pada waktu penerimaan • Derau • Penambahan data yg tidak perlu pada saat transmisi data

4. Arah Transmisi • Menyatakan arah isyarat dalam media transmisi • Simplex / One way • Tidak dapat bertindak sebagai pengirim dan penerima sekaligus • Half-Duplex • Mengirim dan menerima data bergantian • Full-Duplex • Mengirim dan menerima data berbarengan

5. Media Transmisi • Penghubung antara pengirim dan penerima u/ melewatkan data • Media kabel • Media nirkabel • Media Kabel • Twisted Pair Cable • UTP • STP • Coaxial • Fiber Optic

6. Jaringan Komputer • Hubungan dua atau lebih komputer yang bertujuan u/ melakukan pertukaran data • Memungkinkan berbagi sumberdaya • Jenis jaringan menurut rentang geo • LAN • Mencakup area yg terbatas (<1 Km) • MAN • Mencakup area dg rentang satu kota (10-45 Km) • WAN • Menghubungkan antar kota atau lebih luas lagi.

7. Topologi Jaringan • Susunan komputer secara fisik dalam suatu jaringan • Bus • Ring • Star • Extended Star • Hierarchial • Mesh

8. Bus Topology • All of its nodes connected directly to one link • No other connections between nodes • Each host is wired to a common wire. • One advantage of this topology is that all hosts are connected to each other, and thus, can communicate directly. • One disadvantage of this topology is that a break in the cable disconnects hosts from each other. • Enables all networking devices to see all signals from all other devices • Traffic problems and collisions are common.

9. Ring Topology • Single closed ring consisting of nodes and links. • Each node connected to only two adjacent nodes. • All devices wired directly to each other. • In order for information to flow, each station must pass the information to its adjacent station.

10. Star Topology • Has a central node with all links to other nodes radiating from it and allows no other links. • Its primary advantage is that it allows all other nodes to communicate with each other, conveniently. • Its primary disadvantage is that if the central node fails, the whole network becomes disconnected.. • The flow of all information would go through one device.

11. Extended Star Topology • Repeats a star topology, except that each node that links to the center node is, also, the center of another star. • The advantage of this is that it keeps wiring runs shorter, and limits the number of devices that need to interconnect to any one central node. • An extended star topology is very hierarchical, and information is encouraged to stay local

12. Hierarchical Topology • Similar to the extended star topology • uses a trunk node from which it, then, branches to other nodes. • The trunk is a wire that has several layers of branches. • The flow of  information is hierarchical.

13. Mesh Topology • Every node is linked directly to every other node. • The advantages are that • Should any link fail to function, information can flow through any number of other links to reach its destination. • Allows information to flow along many paths on its way through the network. • The primary physical disadvantage is the amount of media for the links, and the amount of connections to the links becomes overwhelming. • Depends greatly on the devices used.

14. Perangkat Interkoneksi Antarjaringan • Interkoneksi Antarjaringan • Hubungan antara dua buah jaringan atau lebih. • Perangkatnya • Repeater • Bridge • Router • Switch / Hub