Transcript Distributed Systems - Department of Information Technology

1DT066
DISTRIBUTED INFORMATION SYSTEMS
Course Summary
INTRODUCTION TO INTERNET
Internet overview
 What’s a protocol?
 Network edge, core, access
network

packet-switching vs. circuitswitching
Internet/ISP structure
 Internet protocol stack
 [Book] Kurose et al. Ch. 1

Introduction

APPLICATION LAYER

Application architectures

application service
requirements:
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
client-server
P2P
hybrid
reliability, bandwidth, delay
Internet transport service
model
connection-oriented, reliable:
TCP
 unreliable, datagrams: UDP
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




HTTP
FTP
SMTP, POP, IMAP
DNS
P2P: BitTorrent, Skype
[Book] Kurose et al. Ch. 2
2: Application Layer

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
r Specific protocols:
TRANSPORT LAYER

Principles behind transport layer services:
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Instantiation and implementation in the Internet
UDP
 TCP
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
[Book] Kurose et al. Ch. 3
Transport Layer

multiplexing, demultiplexing
reliable data transfer
flow control
congestion control
NETWORK LAYER
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Datagram format
IPv4 addressing
IPv6
[Book] Kurose et al. Ch. 4
4.5 Routing algorithms
4.6 Routing in the
Internet
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
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Link state
Distance Vector
Hierarchical routing
RIP
OSPF
BGP
4.7 Broadcast and
multicast routing
Network Layer
Introduction
 Virtual circuit and
datagram networks
 What’s inside a router
 IP: Internet Protocol

LINK LAYER
Link Layer Services
 Multiple Access Protocols


channel partitioning, by time, frequency or code


random access (dynamic),

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Time Division, Frequency Division
ALOHA, S-ALOHA, CSMA, CSMA/CD
taking turns

polling from central site, token passing
Address Resolution Protocol (ARP)
 [Book] Kurose et al. Ch. 5

NETWORK SECURITY
Basic techniques…...
cryptography (symmetric and public)
 message integrity
 digital signature


secure email
Operational Security: firewalls and IDS
[Book] Kurose et al. Ch. 8
8-7
…. used in many different security scenarios
Operating Systems

Brief introduction to operation systems
Major operating systems components
 Basic computer system organization
 Computer and network architecture

8
understand OS and how middleware is supported by
the OS at the nodes of a distributed system
 [Book] Coulouris et al. Ch. 7

DISTRIBUTED SYSTEMS
Definitions of distributed systems and comparisons to
centralized systems.
 The characteristics of distributed systems.
 The eight forms of transparency.
 The basic design issues.
 [Book] Coulouris et al. Ch. 1 and 2

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MIDDLEWARES
The basic conceptual framework for middleware in
distributed systems.
 Definition of RPC and how it works.
 Basics of web services technologies.
 [Book] Coulouris et al. Ch. 5 and 9

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TIME, COORDINATION AND AGREEMENT
 Timing


issues
Synchronizing physical clocks.
Logical time and logical clocks.
 Distributed
coordination and mutual exclusions.
 Coordination.
 Elections


Ring-based algorithm
Bully algorithm
 Multicast
communication.
 [Book] Coulouris et al. Ch. 14 and 15.
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CONCURRENCY CONTROL

Transaction concepts:
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ACID
Transaction commands
Roles of distributed components in transactions
Two-phase commit

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phase one: voting
phase two: completion
Distributed Transactions and Distributed Deadlocks
 [Book] Coulouris et al. Ch. 16
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