CIS 455 / 555: Internet and Web Systems (Spring 2016)

Instructor Andreas Haeberlen
Location: 560 Levine Hall
Office hour: Mondays 1-2pm
Time and location Location: Berger Auditorium
Mondays + Wednesdays 10:30am - noon
Teaching assistants Bowen Bao, bowenbao@seas.upenn.edu
Office hour: Mondays 2-4pm (DRLB Room 4C6)

Shayan Patel, shayanp@seas.upenn.edu
Office hour: Tuesdays noon-2pm (Moore 207)

Kelly Tan, kellytan@seas.upenn.edu
Office hour: Wednesdays 1:30-3pm (Towne 313)

Anwesha Das, anwesha@seas.upenn.edu
Office hour: Wednesdays 3-5pm (5th floor bump space)

Deepti Panuganti, pdeepti@seas.upenn.edu
Office hour: Thursdays 3-5pm (Towne 307)

Haoyun Qiu, haoyun@seas.upenn.edu
Office hour: Fridays 3:30-5:30pm (Moore 100A)

Course description This course focuses on the issues encountered in building Internet and web systems: scalability, interoperability (of data and code), atomicity and consistency models, replication, and location of resources, services, and data. Note that it is not about building database-backed or PHP/JSP/Servlet-based web sites (for this, see CIS 450/550 or NETS 212). Here, we will learn how a Servlet server itself is built!

We will examine how XML standards enable information exchange; how web services support cross-platform interoperability (and what their limitations are); how "cloud computing" services work; how to do replication and Akamai-like content distribution; and how application servers provide transaction support in distributed environments. We will study techniques for locating machines, resources, and data (including directory systems, information retrieval indexing and ranking, web search, and publish/subscribe systems); we will discuss collaborative filtering and mining the Web for patterns; we will investigate how different architectures support scalability (and the issues they face). We will also examine the ideas that have been proposed for tomorrow's Web, including the "Semantic Web", and see some of the challenges, research directions, and potential pitfalls.

An important goal of the course is not simply to discuss issues and solutions, but to provide hands-on experience with a substantial implementation project. This semester's project will be a peer-to-peer implementation of a Google-style search engine, including distributed, scalable crawling; indexing with ranking; and even PageRank. We will also incorporate the use of topic-specific recognizers and mash-ups.

As a side effect of the material of this course, you will learn about some aspects of large-scale software development: assimilating large APIs, thinking about modularity, reading other people's code, managing versions, debugging, and so on.

CIS555 is now a core course for the MSE degree; for details, please see the MSE requirements. The Daily Pennsylvanian published a nice article about CIS455/555.

Format The format will be two 1.5-hour lectures per week, plus assigned readings from handouts. There will be regular homework assignments and a substantial implementation project with experimental validation and a report. There will also be a midterm and a final exam.
Prerequisites This course expects familiarity with threads and concurrency, as well as strong Java programming skills. Those highly proficient in another programming language, such as C++ or C#, should be able to translate their skills easily. The course will require a considerable amount of programming, as well as the ability to work with your classmates in teams.
Texts and readings Distributed Systems: Principles and Paradigms, 2nd ed, by Tanenbaum and van Steen, Prentice Hall (ISBN 978-0132392273, $137.41 on Amazon)
Additional materials will be provided as handouts or in the form of light technical papers.
Grading Homework 32%, midterm 15%, final exam 15%, project 33%, participation 5%.
Other resources We will be using Piazza for course-related discussions; please sign up here. A reading list is also available.
Assignments The homework assignments will be available here. You can submit your solutions online (requires PennKey login).
Final project Wondering what you will be able to do at the end of this class? Here is an example from Spring 2014:
 
AVERNUS search page
Yang, Chenyang, Xuan, and Sitong
Example result
Chenyang Yu, Xuan Zheng, Sitong Zhou, and Yang Wu built a scalable, cloud-based search engine called "AVERNUS", which consists of a scalable, distributed crawler, an indexer, a PageRank engine, and a web frontend. AVERNUS also has a number of advanced features, such as image search, and it is partly based on a new MapReduce framework that was implemented from scratch by the authors. Google donated four Nexus 7 tablets as a prize for the best project, and each member of the AVERNUS team received one of the tablets. Honorable mentions went to Team "YASE" (Chaoyi Huang, Xinchao Shen, Huinan Yu, Mengli Li), whose search engine offers a number of extra services - such as weather forecasts and shopping results - and to Team "Googol" (Adam Colombo, Alyssa Battistuz, Joshua Stone, Sean Welleck), whose solution uses geolocation to improve the relevance of its results.

You can read more about previous Google Award winners and their projects in the CIS455/555 Hall of Fame.

Schedule
Date Topic Details Reading Remarks
Jan 13 Introduction Principles of building systems
Project management & debugging tips
Lampson: Hints for Computer Systems Design  
Jan 18 MLK day — no class
Jan 20 Server architectures Common server types: Web, application
Architectures: client/server, P2P, multi-tier
Marshall: HTTP Made Really Easy
Tanenbaum 3.1
HW0
Jan 25 Server architectures Threads, monitors, signals, producer-consumer
Thread pools, event-driven programming
Krishnamurthy/Rexford Chapter 4
Krohn: OKWS paper
HW1
Jan 27 Naming & locating resources Naming and directories; search strategies
LDAP; DNS; DNSSEC
Wikipedia: DNS
Marshall: LDAP intro
HW0 due
Feb 1  
Feb 3 Indexing Document indexing
B+ tree
Comer: The Ubiquitous B-Tree  
Feb 8 Representing data Data representations, schemas
JPEG, MP3, and QT
XML
XPath and XSLT
Doan, Halevy, Ives: XML  
Feb 10 Representing data (contd.) XSLT Tutorial HW1 MS1 due
Feb 15 Decentralized systems Partly and fully decentralized systems
Key-based routing
Druschel and Rodrigues: Peer-to-peer systems HW2
Feb 17 Class canceled
Feb 22 Key-based routing Partitioning and consistent hashing
BitTorrent, Chord
Stoica et al.: Chord HW1 MS2 due (on Feb 19)
Feb 24 Retrieving data Crawling basics
Publish-subscribe; collaborative filtering
Mercator; XFilter
Altinel and Franklin: XFilter
Heydon and Najork: High-Performance Web Crawling
 
Feb 29 Storing data Cloud file system Ghemawat et al.: The Google File System
HW2 MS1 due
(on Mar 4)
Mar 2 Midterm
Mar 5–13 Spring break -- no class
Mar 14 Processing data MapReduce programming model Dean and Ghemawat: MapReduce  
Mar 16 Processing data (contd.) Hadoop Shvachko: Apache Hadoop: The Scalability Update  
Mar 21 Code interoperability Remote procedure calls
Web services
SOAP, WSDL, REST
Service composition
XQuery
Tanenbaum chapters 4.2 and 10.3 HW2 MS2 due; HW3
Mar 23 Code interoperability (contd.) XQuery tutorial  
Mar 28 Documents and ranking Information retrieval models
Web connectivity
Ranking
Web crawlers
HITS and PageRank
Baeza-Yates Chapters 2 and 8
Kleinberg: HITS
Brin and Page: PageRank
Brin and Page: Google
Wired article on Google
Form project groups
Apr 4 Documents and ranking (contd.)
Mar 30 No class -- Andreas at MPI-SWS
Apr 6 The Cloud Utility computing model
AWS basics; EC2+EBS
Armbrust: A view of Cloud Computing HW3 due
Apr 11 Transactions Application server and TP monitor architectures
ACID properties
Two-phase commit
Tanenbaum chapters 8.5-8.6  
Apr 13 Fault tolerance Replicated state machines
Consensus; Paxos algorithm
Rational behavior and Byzantine faults
Lamport: Paxos (Alternative version)
Schneider: State Machine Approach
Project plan due
Apr 18 Security Web security
Views, ACLs, capabilities; crypto basics
Kerberos; TLS
Tanenbaum chapter 9  
Apr 20 Incremental processing Bigtable
Percolator
Peng and Dabek: Percolator  
Apr 25 Special topics Accountability
Differential privacy
Narayanan and Shmatikov: Robust Deanonymization  
Apr 27 Second midterm
May 2–10
Project demos and reports
Previous versions Spring 2014 |  Spring 2013 |  Spring 2012 |  Spring 2011 (taught by Prof. Ives until 2010, and in Fall 2015)