p eer to peer networks and performance

07:49:49 PM H. Levy P2P+Performance 1

Peer to Peer networks and Performance

Hanoch Levy (hanoch at cs.tau.ac.il)Office: Kaplun 511

Office hours: by appointment

07:49:49 PM H. Levy P2P+Performance 2/23

Course Information

Lectures: Wed 9-12 Shreiber 8

Web site: http://www.cs.tau.ac.il/~hanoch/And follow the link: Advanced topics in Computer-Networks – Peer-to-Peer Networks


Course Objective

1. Study P2P networks2. Open the door for research in this area

(Master/ Ph.D) 3. Cover both: Theoretical background and

advanced material


Course Approach

Prerequisites: Course in computer Networks/ Equivalent / teacher approval

Requirements: Most material is New (articles) Requires some analytic models

Approach: Theoretical background (performance:

elementary queueing theory) – frontal lectures by teacher.

Recent material: (articles) – lectures by students


Course Structure and requirements

First half of semester: Teacher lectures

2nd half of semester – student lectures. Each student gets one paper – and

covers one paper in 45 minutes.


Course requirements

First half (theoretical): In Class Exam (50-60% of grade) exam time: see Mazkirut HW assignments

2nd Half: Give a good lecture. (40-50% of grade) Active participation will benefit a bonus

Overflow students (if any): lecture can be replaced by special assignment by lecturer.


Course Information

1. Queueing Theory, L. Kleinrock, Vol I, Wiley (hard copy)

2. Online books: 1. Web site:

http://web2.uwindsor.ca/math/hlynka/qonline.html(search “queueing hlynka)

2. Introduction to Queueing Theory (2nd edition). Robert B. Cooper. 1981. 347 pp. This classic book is available on line through Robert Cooper's home page. The link to the book is: http://www.cse.fau.edu/~bob/publications/IntroToQueueingTheory_Cooper.pdf The solution manual (by Borge Tolt, 182 pages, 1981) is available online at http://www.cse.fau.edu/%7Ebob/publications/QueueingTheory_solns.pdf

Supporting Books (theoretical part)


Course Information

3. Queueing Theory. Ivo Adan and Jacques Resing. 2001. 180 pp.

4. Queues: –A Course in Queueing Theor. Moshe Haviv. October 1, 2009. New and complete.

5. more…

Supporting Books (theoretical part – cont )


Motivation

Last 10-15 years: communications revolution Internet + Computer communications

Is a key factor of the Information revolution Implications

A drastic change of some aspects of life Revolution is affected by life Technology drives applications Applications drive technology


Motivation (cont)

Applications / technology / research rapidly change over time

If want to stay in frontier: => Research material very

dynamic => Course material very dynamic


Objectives Computer Networking course: Internet infra-structure 1 Introduction and Layering 2 Physical Layer, Data Link Layer, MAC Protocols 3 Hubs, Bridges, SwitchesData Link Layer 4 Switching UnitsSTP, Switching Fabric 5 Scheduling: Buffer Management Scheduling, WFQ example 6 Network Layer: RoutingRouting 7 Reliable Data TransferIP 8 End to End ProtocolsARQ 10 Flow Control, Congestion ControlTCP flow & congestion control 11 Network SecurityNetwork Sniffing (no slides) 12 DNS, HTTPTCP (state chart) 13 DDoS ALL – operations of network of networks.


Objectives (2)

Advanced Material – network development following technology Peer to Peer (P2P): Bittorent, Skype

Songs /movies / video-on-demand/video online


Backbone ISPISP ISP

Internet Physical InfrastructureResidential access

Cable Fiber DSL Wireless

Campus access, e.g.,

Ethernet Wireless

The Internet is a network of networks

Each individually administrated network is called an Autonomous System (AS)


Data Networks

Set of interconnected nodes exchange information sharing of the transmission circuits= "switching". many links allow more than one path between

every 2 nodes. network must select an appropriate path for each

required connection.


Real Network


Peer to Peer – what is it ?

“Historical” Internet : send data from A to K.

Client-server model: A = server = data source K = client data consumer

If C wants too – get from A (unicast or broadcast)


Peer to Peer – what is it

A (source) sends to K.

K (client) may become now a server.

K sends to C (another client).


Peer to Peer – what the diff ?

A K

Server Client (user)

Commercial Private

Costs“Cost free”

Charges“contributes”

Legal obligations

Legal??


Peer to Peer – what the diff ?

A K

Small number

Huge number

Reliable Non reliable

plannedunplanned

Huge traffic80%!!!!


Peer to Peer – How important

• 0% of costs

• O(0)% of revenues

• 0% of planning

• “Nothing”

• BUT: 80% of traffic

• cannot disregard…

• If you can’t beat them, join them…


Peer to Peer – Historical View

• Networks developed for 40+ years

• Internet – started developing late 70’s early 80’s

• Distributed, Semi Organized

• ATM – developed throughout the 90’s

• huge amount of money!!!

• Very well organized network

• “failed”

• P2P – started in the 00’s

• VERY unorganized

• 80% of traffic (though SMALL % of money)


Peer to Peer – WHY ??

Legal (this is how it started…) Broadcast is not really

implemented A is bottleneck Resource Utilization: K is

idle X% (95?)of the day Communications (costs!!) CPU

Scalability Issues:

BW cost? Free ride? Files? Video on demand?

Stream (video Broadcast)


Questions for this course

Is it viable? Does it have life of itself? Can it survive without economy?

Can you carry 80% of traffic without make charges?

Are users (clients) going to let it go? Are ISP’s going to be happy?

Can 80% go unnoticeable without economic bodies “join the party”

E.g – will ISP take advantage of it? Is it the right way to plan a net?


Theory

Many network models – based on stochastic modeling

Queueing systems Stochastic processes

P2P models – included Objective: study basic stochastic /

queueing models Elementary Queueing theory

p eer to peer networks and performance

Documents