University of British Columbia CICS 515 (Part 1) Internet Computing Lecture 1 - Overview - PowerPoint PPT Presentation

Loading...

PPT – University of British Columbia CICS 515 (Part 1) Internet Computing Lecture 1 - Overview PowerPoint presentation | free to view - id: 761b8b-ZWRjY



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

University of British Columbia CICS 515 (Part 1) Internet Computing Lecture 1 - Overview

Description:

CICS 515 (Part 1) Internet Computing Lecture 1 - Overview Instructor: Dr. Son T. Vuong Email: vuong_at_cs.ubc.ca May 8, 2012 The World Connected Introduction ... – PowerPoint PPT presentation

Number of Views:139
Avg rating:3.0/5.0
Slides: 86
Provided by: DonT320
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: University of British Columbia CICS 515 (Part 1) Internet Computing Lecture 1 - Overview


1
University of British Columbia CICS 515 (Part
1) Internet Computing Lecture 1 - Overview
  • Instructor Dr. Son T. Vuong
  • Email vuong_at_cs.ubc.ca
  • May 8, 2012
  • The World Connected

2
Information and Organization
  • Instructor Dr. Son Vuong
  • Email vuong_at_cs.ubc.ca
  • Office Hours T, Th 100-200pm (CS 329)
  • TA
  • Jonatan Schroeder jonatan_at_cs.ubc.ca
  • Shahed Alam malam_at_cs.ubc.ca
  • Lectures T, Th 11am-1 pm in DMP 110
  • Lab Th 2-4 pm (CS 045/051)

3
Text and Workload
  • Text Computer Networking A Top Down Approach
    Featuring the Internet, 6th edition. Jim
    Kurose, Keith Ross. Addison-Wesley, April 2012.
  • Course Load
  • 2 Projects/Asgmts (20)
  • 2 Quizzes (10)
  • Midterm (25)
  • Final exam (45)
  • Bonus for class participation, BlueCT Peerwise
    (4)
  • Late penalty 52i , 0lt i lt 3 (i days late)
  • Website www.icics.ubc.ca/cics515
  • Vista http//www.vista.ubc.ca/ (idpwdCWL)

4
Revised CISC 515 Outline (Tentative)
  1. (T - 08/5) Overview (Chapter 1) P1
  2. (Th - 10/5) Application Layer (The Web and HTTP)
    (Ch 2)
  3. (T - 15/5) WebCache and Transport Layer (Ch 3)
  4. (Th - 17/5) Transport Layer (Ch 3)
  5. (T - 22/5) Transport Layer (TCP) (Ch 3) Quiz1
  6. (Th - 24/5) TCP Congestion (P1) P2
  7. (T-29/5) IP (Ch 4) IPv6 (Ch 4) Midterm
  8. (Th - 31/6) Other Protocols (ICMP, DHCP, DNS),
    Routing (RIP, OSPF) (Ch 4)
  9. (T - 05/6) Routing (RIP, OSPF, BGP) (Ch 4)
  10. (Th- 07/6) Data Link protocols (Ethernet) (Ch 5)
    (P2)
  11. (T- 12/6) Wireless Networks (WiFi) (Ch 6) Quiz2
  12. (Th-14/6) Review 13. (F-15/6) Final Exam

5
Chapter 1 Introduction
  • Our goal
  • get context, overview, feel of networking
  • more depth, detail later in course
  • approach
  • descriptive
  • use Internet as example
  • Overview
  • whats the Internet
  • whats a protocol?
  • network edge
  • network core
  • access net, physical media
  • Internet/ISP structure
  • performance loss, delay
  • protocol layers, service models
  • history

6
Chapter 1 roadmap
  • 1.1 What is the Internet?
  • 1.2 Network edge
  • 1.3 Network core
  • 1.4 Network access and physical media
  • 1.5 Internet structure and ISPs
  • 1.6 Protocol layers, service models
  • 1.7 Delay loss in packet-switched networks
  • 1.8 History

7
Whats the Internet nuts and bolts view
  • millions of connected computing devices hosts,
    end-systems
  • PCs workstations, servers
  • PDAs phones, toasters
  • running network apps
  • communication links
  • fiber, copper, radio, satellite
  • transmission rate bandwidth
  • routers forward packets (chunks of data)

8
Cool internet appliances
IP picture frame http//www.ceiva.com/
Web-enabled toasterweather forecaster
Worlds smallest web server http//www-ccs.cs.umas
s.edu/shri/iPic.html
9
Whats the Internet nuts and bolts view
  • protocols control sending, receiving of msgs
  • e.g., TCP, IP, HTTP, FTP, PPP
  • Internet network of networks
  • loosely hierarchical
  • public Internet versus private intranet
  • Internet standards
  • RFC Request for comments
  • IETF Internet Engineering Task Force

router
workstation
server
mobile
local ISP
regional ISP
company network
10
Whats the Internet a service view
  • communication infrastructure enables distributed
    applications
  • Web, email, games, e-commerce, database., voting,
    file (MP3) sharing
  • communication services provided to apps
  • connectionless
  • connection-oriented
  • cyberspace Gibson
  • a consensual hallucination experienced daily by
    billions of operators, in every nation, ...."

11
Uses of Internet
  • Business Applications
  • Home Applications
  • Mobile Users
  • Social Issues

12
Business Applications of Networks
  • A network with two clients and one server.

13
Business Applications of Networks (2)
  • The client-server model involves requests and
    replies.

14
Home Network Applications
  • Access to remote information
  • Person-to-person communication
  • Interactive entertainment
  • Electronic commerce

15
Home Network Applications (2)
  • In peer-to-peer system there are no fixed
    clients and servers.

16
Home Network Applications (3)
  • Some forms of e-commerce.

17
Mobile Network Users
  • Combinations of wireless networks and mobile
    computing.

18
Classification of Networks
  • Classification of interconnected processors by
    scale.

19
Example Networks
  • The Internet
  • Connection-Oriented Networks X.25, Frame
    Relay, and ATM
  • Ethernet
  • Wireless LANs 80211 (WiFi)

20
Network Perspective
  • Network users services that their applications
    need, e.g., guarantee that each message it sends
    will be delivered without error within a certain
    amount of time
  • Network designers cost-effective design e.g.,
    that network resources are efficiently utilized
    and fairly allocated to different users
  • Network providers system that is easy to
    administer and manage e.g., that faults can be
    easily isolated and it is easy to account for
    usage

21
Connectivity
  • Building Blocks
  • links coax cable, optical fiber...
  • nodes general-purpose workstations...
  • Direct Links
  • point-to-point
  • multiple access

22
Switched Networks
  • A network can be defined recursively as
  • two or more nodes connected
  • by a physical link,
  • or by two or more networks
  • connected by one
  • or more nodes
  • Internetworks
  • Internet vs internet

23
A closer look at network structure
  • network edge applications and hosts
  • network core
  • routers
  • network of networks
  • access networks, physical media communication
    links

24
Chapter 1 roadmap
  • 1.1 What is the Internet?
  • 1.2 Network edge
  • 1.3 Network core
  • 1.4 Network access and physical media
  • 1.5 Internet structure and ISPs
  • 1.6 Protocol layers, service models
  • 1.7 Delay loss in packet-switched networks
  • 1.8 History

25
The network edge
  • end systems (hosts)
  • run application programs
  • e.g. Web, email
  • at edge of network
  • client/server model
  • client host requests, receives service from
    always-on server
  • e.g. Web browser/server email client/server
  • peer-peer model
  • minimal (or no) use of dedicated servers
  • e.g. Gnutella, KaZaA

26
Network edge connection-oriented service
  • Goal data transfer between end systems
  • handshaking setup (prepare for) data transfer
    ahead of time
  • Hello, hello back human protocol
  • set up state in two communicating hosts
  • TCP - Transmission Control Protocol
  • Internets connection-oriented service
  • TCP service RFC 793
  • reliable, in-order byte-stream data transfer
  • loss acknowledgements and retransmissions
  • flow control
  • sender wont overwhelm receiver
  • congestion control
  • senders slow down sending rate when network
    congested

27
Network edge connectionless service
  • Goal data transfer between end systems
  • same as before!
  • UDP - User Datagram Protocol RFC 768
    Internets connectionless service
  • unreliable data transfer
  • no flow control
  • no congestion control
  • Apps using TCP
  • HTTP (Web), FTP (file transfer), Telnet (remote
    login), SMTP (email)
  • Apps using UDP
  • streaming media, teleconferencing, DNS, Internet
    telephony

28
Chapter 1 roadmap
  • 1.1 What is the Internet?
  • 1.2 Network edge
  • 1.3 Network core
  • 1.4 Network access and physical media
  • 1.5 Internet structure and ISPs
  • 1.6 Protocol layers, service models
  • 1.7 Delay loss in packet-switched networks
  • 1.8 History

29
The Network Core
  • mesh of interconnected routers
  • the fundamental question how is data transferred
    through net?
  • circuit switching dedicated circuit per call
    telephone net
  • packet-switching data sent thru net in discrete
    chunks

30
Switching Strategies
  • Circuit switching dedicated circuit
    send/receive a bit stream
  • original telephone network
  • Packet switching store-and-forward send/receive
    messages (packets)
  • Internet

31
Switching Strategies
  • (a) Circuit switching (b) Message switching
    (c) Packet switching

32
Nodal delay
  • dproc processing delay
  • typically a few microsecs or less
  • dqueue queuing delay
  • depends on congestion
  • dtrans transmission delay
  • L/R, significant for low-speed links
  • dprop propagation delay
  • a few microsecs to hundreds of msecs

33
Packet switching versus circuit switching
  • Is packet switching a slam dunk winner?
  • Great for bursty data
  • resource sharing
  • simpler, no call setup
  • Excessive congestion packet delay and loss
  • protocols needed for reliable data transfer,
    congestion control
  • Q How to provide circuit-like behavior?
  • bandwidth guarantees needed for audio/video apps
  • still an unsolved problem (chapter 6)

34
Packet-switching store-and-forward
L
R
R
R
  • Takes L/R seconds to transmit (push out) packet
    of L bits on to link or R bps
  • Entire packet must arrive at router before it
    can be transmitted on next link store and
    forward
  • delay 3L/R
  • Example
  • L 7.5 Mbits
  • R 1.5 Mbps
  • delay 3x 5 sec 15 sec

35
Packet Switching Message Segmenting
  • Now break up the message into 5000 packets
  • Each packet 1,500 bits
  • 1 msec to transmit packet on one link
  • pipelining each link works in parallel
  • Delay reduced from 15 sec to 5.002 sec

36
Packet Switching Message Segmenting
L
R
R
R
R
  • Now assume the message/packets go through 2
    additional switches (over the path of 4 switches)
  • What is the total delay to send the message
    without breaking into packets (i.e.
    non-pipelining) ?
  • What is the total delay to send the message as
    5000 packets (i.e. pipelining) ?

37
Q 1.1  Peer Instruction packet switching
  • Now assume the message/packets go through 2
    additional switches (over the path of 4 switches)
    What is the total delay to send the message as
    5000 packets (i.e. pipelining) ?
  • Answer
  • (A) 25 s  (B) 15 s  (C) 5.002 s  (D) 5.004 s
  • (E) None of the above

38
Q 1.1  Peer Instruction packet switching
  • Now assume the message/packets go through 2
    additional switches (over the path of 4 switches)
    What is the total delay to send the message as
    5000 packets (i.e. pipelining) ?
  • Answer
  • (A) 25 s  (B) 15 s  (C) 5.002 s  (D) 5.004 s
  • (E) None of the above

39
Packet-switched networks forwarding
  • Goal move packets through routers from source to
    destination
  • well study several path selection (i.e.
    routing)algorithms (chapter 4)
  • datagram network
  • destination address in packet determines next
    hop
  • routes may change during session
  • analogy driving, asking directions
  • virtual circuit network
  • each packet carries tag (virtual circuit ID),
    tag determines next hop
  • fixed path determined at call setup time, remains
    fixed thru call
  • routers maintain per-call state

40
Addressing and Routing
  • Address byte-string that identifies a node
  • usually unique
  • Routing how to forward messages towards the
    destination node based on its address
  • Types of addresses
  • unicast node-specific
  • broadcast all nodes on the network
  • multicast some subset of nodes on the network

41
Multiplexing
  • Time-Division Multiplexing (TDM)
  • Frequency-Division Multiplexing (FDM)

42
Circuit Switching FDMA and TDMA
43
Time Division Multiplexing (T1 Carrier)
  • The T1 carrier (1.544 Mbps).

(1 bit 24 slots 8 bits/slot) 8000 frames/s
193 bits/frame 8000 frames/s 1.544 Mbps
44
Peer Instruction 1.1 T1 TDM Question
  • How long does it take to send a file of 640,000
    bits from host A to host B over a (sub)channel (a
    circuit) in a T1 TDM based circuit-switched
    network?
  • Overall T1 TDM carrier capacity is 1.536 Mbps
  • Data transmission uses one of the 24 slots of the
    T1 carrier
  • 500 msec to establish end-to-end circuit
  • Work it out!
  • (A) 510 ms (B) 1500 ms (C) 2.5 s (D) 10.5 s
  • (E) None of the above

45
1.1 Peer Instruction T1 TDM Answer
  • How long does it take to send a file of 640,000
    bits from host A to host B over a (sub)channel (a
    circuit) in a T1 TDM based circuit-switched
    network?
  • Overall TDM channel capacity is 1.536 Mbps (T1
    1.544 Mbps with 8Kbps framing)
  • Data transmission uses one of the 24 slots of the
    TDM channel
  • 500 msec 0.5s to establish end-to-end circuit
  • Answer Each circuit 1.536Mbps/24 64Kbps
  • Tx(file) 640Kb/64Kbps 10s plus Tsetup
  • (A) 510 ms (B) 1500 ms (C) 2.5 s (D) 10.5 s
  • (E) None of the above

46
Peer Instruction 1.1 T1 TDM Question
  • How long does it take to send a file of 640,000
    bits from host A to host B over 5 (sub)channels
    (circuits) in a T1 TDM based circuit-switched
    network?
  • Overall T1 TDM carrier capacity is 1.536 Mbps
  • Data transmission uses one of the 24 slots of the
    T1 carrier
  • 500 msec to establish end-to-end circuit
  • Work it out!
  • (A) 510 ms (B) 1500 ms (C) 2.5 s (D) 10.5 s
  • (E) None of the above

47
1.1 Peer Instruction T1 TDM Answer
  • How long does it take to send a file of 640,000
    bits from host A to host B over 5 (sub)channel
    (circuits) in a T1 TDM based circuit-switched
    network?
  • Overall TDM channel capacity is 1.536 Mbps (T1
    1.544 Mbps with 8Kbps framing)
  • Data transmission uses one of the 24 slots of the
    TDM channel
  • 500 msec 0.5s to establish end-to-end circuit
  • Answer Each circuit 1.536Mbps/24 64Kbps
  • Tx(file) 640Kb/(5x64Kbps) 2s plus Tsetup
  • (A) 510 ms (B) 1500 ms (C) 2.5 s (D) 10.5 s
  • (E) None of the above

48
Statistical Multiplexing (ATDM)
  • On-demand time-division, rather than fixed (STDM)
  • Schedule link on a per-packet basis
  • Packets from different sources interleaved on
    link
  • Buffer packets that are contending for the link
  • Packet queue may be processed FIFO
  • Buffer (queue) overflow is called congestion

ATDM or Concentrator
49
Chapter 1 roadmap
  • 1.1 What is the Internet?
  • 1.2 Network edge
  • 1.3 Network core
  • 1.4 Network access and physical media
  • 1.5 Internet structure and ISPs
  • 1.6 Protocol layers, service models
  • 1.7 Delay loss in packet-switched networks
  • 1.8 History

50
Protocols
  • Building blocks of a network architecture
  • Each protocol object has two different
    interfaces
  • service operations on this protocol
  • peer-to-peer (protocol) messages exchanged with
    peer
  • Term protocol is overloaded
  • specification of peer-to-peer interface
  • module that implements this interface

51
Interfaces (Protocol and Service)
Host 1
Host 2
SERVICE
High-level
High-level
interface
object
object
PROTOCOL
Protocol
Protocol
Peer-to-peer
interface
52
Whats a protocol?
  • human protocols
  • whats the time?
  • I have a question
  • introductions
  • specific msgs sent
  • specific actions taken when msgs received, or
    other events
  • network protocols
  • machines rather than humans
  • all communication activity in Internet governed
    by protocols

protocols define format, order of msgs sent and
received among network entities, and actions
taken on msg transmission, receipt
53
Whats a protocol?
  • a human protocol and a computer network protocol

Hi
TCP connection req
Hi
Q Other human protocols?
54
Internet Architecture
  • Defined by Internet Engineering Task Force (IETF)
  • Hourglass Design
  • Application vs Application Protocol (FTP, HTTP)

55
ISO Architecture
56
Reference Models
  • The TCP/IP reference model.

57
Layering
  • Use abstractions to hide complexity
  • Abstraction naturally lead to layering
  • Alternative abstractions at each layer

Host-to-host connectivity
58
Layering logical communication
  • Each layer
  • distributed
  • entities implement layer functions at each node
  • entities perform actions, exchange messages with
    peers

59
Layering logical communication
  • E.g. transport
  • take data from app
  • add addressing, reliability check info to form
    datagram
  • send datagram to peer
  • wait for peer to ack receipt
  • analogy post office

transport
transport
60
Layering physical communication
61
Protocol layering and data
  • Each layer takes data from above
  • adds header information to create new data unit
  • passes new data unit to layer below

source
destination
message
segment
datagram
frame
62
Chapter 1 roadmap
  • 1.1 What is the Internet?
  • 1.2 Network edge
  • 1.3 Network core
  • 1.4 Network access and physical media
  • 1.5 Internet structure and ISPs
  • 1.6 Protocol layers, service models
  • 1.7 Delay loss in packet-switched networks
  • 1.8 History

63
How do loss and delay occur?
  • packets queue in router buffers
  • packet arrival rate to link exceeds output link
    capacity
  • packets queue, wait for turn

A
B
64
1.2 Peer Instruction - Packet Error Prob Question
  • Let p be the bit error probability.  Assume
    packet of length L bits. What's the packet error
    probability in terms of p and L?
  • (A)    (1- p) L
  • (B)    1- pL
  • (C)    1- p L
  • (D)    1- (1-p)L
  • (E)    None of the above

65
1.2 Peer Instruction - Packet Error Prob Answer
  • Let p be the bit error probability.  Assume
    packet of length L bits. What's the packet error
    probability in terms of p and L?
  • (A)    (1- p) L
  • (B)    1- pL prob (not all bits in error)
  • (C)    1- p L
  • (D)    1- (1-p)L
  • (E)    None of the above
  • Answer (D) 
  • prob(a bit not in error) 1-p
  • prob (L bits not in error) (1-p)L
  •    prob(packet error) prob (not all bits not in
    error)
  •                                 1- (1-p)L

66
What Goes Wrong in the Network?
  • Bit-level errors (electrical interference)
    probp
  • Packet-level errors (congestion) 1-(1-p)f
  • Link and node failures
  • Messages are delayed
  • Messages are delivered out-of-order
  • Third parties eavesdrop
  • The key problem is to fill in the gap between
    what
  • applications expect and what the underlying
  • technology provides.

67
Four sources of packet delay
  • 1. nodal processing
  • check bit errors
  • determine output link
  • 2. queueing
  • time waiting at output link for transmission
  • depends on congestion level of router

68
Delay in packet-switched networks
  • 4. Propagation delay
  • d length of physical link
  • s propagation speed in medium (2x108 m/sec)
  • propagation delay d/s
  • 3. Transmission delay
  • Rlink bandwidth (bps)
  • Lpacket length (bits)
  • time to send bits into link L/R

Note s and R are very different quantities!
69
Nodal delay
  • dproc processing delay
  • typically a few microsecs or less
  • dqueue queuing delay
  • depends on congestion
  • dtrans transmission delay
  • L/R, significant for low-speed links
  • dprop propagation delay
  • a few microsecs to hundreds of msecs

70
Queueing delay (revisited)
  • Rlink bandwidth (bps)
  • Lpacket length (bits)
  • aaverage packet arrival rate

traffic intensity La/R
  • La/R 0 average queueing delay small
  • La/R -gt 1 delays become large
  • La/R gt 1 more work arriving than can be
    serviced, average delay infinite!

71
Digression- Simple Queuing Model
  • Queuing system general properties
  • Arrival rate ? a msg/s
  • Service rate µ R/L msg/s Service time
    Ts L/R ? / a s/msg
  • Traffic intensity Utilization factor ? ? /
    µ aL / R
  • Little Formula N ? T a T or T N/a
  • N Nw Ns and T Tw Ts
  • M/M/1 Queue Model (M/M/1 is Kendall notation)
  • Can derive
  • in system N ? / (1- ?) waiting in
    queue Nw ?2 / (1- ?)
  • gt Time in system T N/a Ts / (1- ?)
    (using Little formula)
  • Tw Ts N
    Ts Ts (N1) Ts
  • Waiting time Tw T Ts Ts / (1- ?) - Ts
    (1/ (1- ?) - 1 )Ts
  • ? Ts / (1- ?)
  • N Ts

72
Real Internet delays and routes
  • What do real Internet delay loss look like?
  • Traceroute program provides delay measurement
    from source to router along end-end Internet path
    towards destination. For all i
  • sends three packets that will reach router i on
    path towards destination
  • router i will return packets to sender
  • sender times interval between transmission and
    reply.

3 probes
3 probes
3 probes
73
Real Internet delays and routes
traceroute gaia.cs.umass.edu to www.eurecom.fr
Three delay measements from gaia.cs.umass.edu to
cs-gw.cs.umass.edu
1 cs-gw (128.119.240.254) 1 ms 1 ms 2 ms 2
border1-rt-fa5-1-0.gw.umass.edu (128.119.3.145)
1 ms 1 ms 2 ms 3 cht-vbns.gw.umass.edu
(128.119.3.130) 6 ms 5 ms 5 ms 4
jn1-at1-0-0-19.wor.vbns.net (204.147.132.129) 16
ms 11 ms 13 ms 5 jn1-so7-0-0-0.wae.vbns.net
(204.147.136.136) 21 ms 18 ms 18 ms 6
abilene-vbns.abilene.ucaid.edu (198.32.11.9) 22
ms 18 ms 22 ms 7 nycm-wash.abilene.ucaid.edu
(198.32.8.46) 22 ms 22 ms 22 ms 8
62.40.103.253 (62.40.103.253) 104 ms 109 ms 106
ms 9 de2-1.de1.de.geant.net (62.40.96.129) 109
ms 102 ms 104 ms 10 de.fr1.fr.geant.net
(62.40.96.50) 113 ms 121 ms 114 ms 11
renater-gw.fr1.fr.geant.net (62.40.103.54) 112
ms 114 ms 112 ms 12 nio-n2.cssi.renater.fr
(193.51.206.13) 111 ms 114 ms 116 ms 13
nice.cssi.renater.fr (195.220.98.102) 123 ms
125 ms 124 ms 14 r3t2-nice.cssi.renater.fr
(195.220.98.110) 126 ms 126 ms 124 ms 15
eurecom-valbonne.r3t2.ft.net (193.48.50.54) 135
ms 128 ms 133 ms 16 194.214.211.25
(194.214.211.25) 126 ms 128 ms 126 ms 17
18 19 fantasia.eurecom.fr
(193.55.113.142) 132 ms 128 ms 136 ms
trans-oceanic link
means no reponse (probe lost, router not
replying)
74
Packet loss
  • queue (aka buffer) preceding link in buffer has
    finite capacity
  • when packet arrives to full queue, packet is
    dropped (aka lost)
  • lost packet may be retransmitted by previous
    node, by source end system, or not retransmitted
    at all

75
Performance Metrics
  • Bandwidth (throughput)
  • data transmitted per time unit
  • link versus end-to-end
  • notation
  • KB 210 bytes
  • Mbps 106 bits per second
  • Latency (delay)
  • time to send message from point A to point B
  • one-way versus round-trip time (RTT)
  • components
  • Latency Propagation Transmit Queue
  • Propagation Distance / c (c3, 2.3, 2x108
    m/s)
  • Transmit Size / Bandwidth

76
Bandwidth versus Latency
  • Relative importance
  • 1-byte 1ms vs 100ms dominates 1Mbps vs 100Mbps
  • 25MB 1Mbps vs 100Mbps dominates 1ms vs 100ms
  • Infinite bandwidth
  • RTT dominates
  • Throughput TransferSize / TransferTime
  • TransferTime RTT TransferSize / Bandwidth
  • 1-GB file to 1-Gbps link as 1-MB packet to 1-Mbps
    link

77
Delay x Bandwidth Product
  • Amount of data in flight or in the pipe
  • Example 100ms x 45Mbps 560KB

78
ITU
  • Main sectors
  • Radiocommunications
  • Telecommunications Standardization
  • Development
  • Classes of Members
  • National governments
  • Sector members
  • Associate members
  • Regulatory agencies

79
IEEE 802 Standards
The 802 working groups. The important ones are
marked with . The ones marked with ? are
hibernating. The one marked with gave up.
80
Bad Timing
  • The apocalypse of the two elephants.

81
Chapter 1 roadmap
  • 1.1 What is the Internet?
  • 1.2 Network edge
  • 1.3 Network core
  • 1.4 Network access and physical media
  • 1.5 Internet structure and ISPs
  • 1.6 Protocol layers, service models
  • 1.7 Delay loss in packet-switched networks
  • 1.8 History

82
Internet History
1961-1972 Early packet-switching principles
  • 1961 Kleinrock - queueing theory shows
    effectiveness of packet-switching
  • 1964 Baran - packet-switching in military nets
  • 1967 ARPAnet conceived by Advanced Research
    Projects Agency
  • 1969 first ARPAnet node operational
  • 1972
  • ARPAnet demonstrated publicly
  • NCP (Network Control Protocol) first host-host
    protocol
  • first e-mail program
  • ARPAnet has 15 nodes

83
Internet History
1972-1980 Internetworking, new and proprietary
nets
  • 1970 ALOHAnet satellite network in Hawaii
  • 1973 Metcalfes PhD thesis proposes Ethernet
  • 1974 Cerf and Kahn - architecture for
    interconnecting networks
  • late70s proprietary architectures DECnet, SNA,
    XNA
  • late 70s switching fixed length packets (ATM
    precursor)
  • 1979 ARPAnet has 200 nodes
  • Cerf and Kahns internetworking principles
  • minimalism, autonomy - no internal changes
    required to interconnect networks
  • best effort service model
  • stateless routers
  • decentralized control
  • define todays Internet architecture

84
Internet History
1980-1990 new protocols, a proliferation of
networks
  • 1983 deployment of TCP/IP
  • 1982 SMTP e-mail protocol defined
  • 1983 DNS defined for name-to-IP-address
    translation
  • 1985 FTP protocol defined
  • 1988 TCP congestion control
  • new national networks Csnet, BITnet, NSFnet,
    Minitel
  • 100,000 hosts connected to confederation of
    networks

85
Internet History
1990, 2000s commercialization, the Web, new apps
  • Early 1990s ARPAnet decommissioned
  • 1991 NSF lifts restrictions on commercial use of
    NSFnet (decommissioned, 1995)
  • early 1990s Web
  • hypertext Bush 1945, Nelson 1960s
  • HTML, HTTP Berners-Lee
  • 1994 Mosaic, later Netscape
  • late 1990s commercialization of the Web
  • Late 1990s 2000s
  • more killer apps instant messaging, peer2peer
    file sharing (e.g., Naptser)
  • network security to forefront
  • est. 100 million host, 500 million users
  • backbone links running at Gbps
About PowerShow.com