Internet Structure and Access Networks Quiz

Questions and Answers

Time Division Multiplexing (TDM) _______

Time divided into slots

Frequency Division Multiplexing (FDM) _______

Frequencies divided into (narrow) frequency bands

Traceroute: program displays the route (path) from source to destination and measures the delay from source to each router along the end-end Internet path. _______

Packet-switching

Packet-switching: store-and-forward: packet-switching: hosts break application-layer messages into packets. each packet transmitted at full link capacity. link transmission rate is aka link capacity or link bandwidth. Transmission delay: takes L/R seconds to transmit (push out) L-bit packet into link at R bps Store and forward: entire packet must arrive at router before it can be transmitted on next link End-end delay: 2L/R (above), assuming zero propagation delay (more on delay shortly) Packet-switching: queueing delay, loss: packets will queue, waiting to be transmitted on output link packets queue in router buffers _______

arrival rate to link (temporarily) exceeds output link capacity: packet loss packets can be dropped (lost) if memory (buffer) in router fills up Signup and view all the answers

Packet delay: four sources 1. Transmission Delay (dtrans): Takes L/R seconds _______

Processing Delay (dproc): Check bit errors, determine output link Signup and view all the answers

Queueing Delay (dqueue): _______

Propagation Delay (dprop) Signup and view all the answers

Throughput: _______

Throughput: rate (bits/time unit) at which bits are being sent from sender to receiver Link capacity (bandwidth) is meant for a specific link. )Throughput(‫) بيقل ال‬Loss(‫ كل ما يحصل عندي أو كل ما يزيد ال‬ Signup and view all the answers

Packet-switching vs Circuit switching: _______

Circuit Switching Signup and view all the answers

Compare Reserves channels _______

Not reserved Signup and view all the answers

Channels reserve can’t be used by any other ongoing communication _______

Can be used by any other ongoing communication Signup and view all the answers

Idle Resource _______

No waiting at the switches Signup and view all the answers

Waiting at the switches if data rate is more than the link tx capacity _______

بيستنى Signup and view all the answers

Internet structure:  Network edge: hosts: clients and servers servers often in data centers  Access networks, physical media: wired, wireless communication links  Network core:  interconnected routers  network of networks Q-How to connect end systems to edge router. Residential access nets ‫زي انك توصل األنترنت في بيتك‬ Institutional access networks (school, company) ‫أدخل ع الشبكة من خالل المكان أو المؤسسة‬ Mobile access networks (Wi-Fi, 4G/5G) ‫من خالل الموبايل‬ Wireless Access Networks:  via base station aka “access point” Physical Media: Media Physical Media Guided Media signals propagate in solid media: copper, fiber coaxial Radio Media Unguided Media signals propagate freely, e.g., radio The Network Core: Q- How is data transmitted through net.  Circuit switching: dedicated circuit per call.  Packet switching: data sent thru net in discrete “chunks”. Shared or Dedicated access among users.  A dedicated internet connection ‫حاجة مخصصة ليك انتا بس‬  A shared cable internet connection ‫أكتر من واحد بيستخدم السرعة أو االتصال‬ Circuit switching:  dedicated resources: no sharing ‫خالص أتحجز‬  circuit-like (guaranteed) performance. Signup and view all the answers