WWW and World Wide Wait:Is it Forever?

Hanoch LevySchool of Computer Science

Tel-Aviv University

November 2000

World Wide Wait

www.xyz.com

Questions (W*)

• Do We Wait? • Where We Wait?• When We wait? • hoW much We Wait? • Why We Wait?• Why Telephone is so great and Web is not? • Will We Wait?

Waiting in Israel

• Our experience: long…• Short Experiment:

– Several sites at non-peak time– 70 KB pages – ISDN line (8 Kbytes/sec)– Avg wait time : 15 seconds– Peak time: worse

Waiting in the World (US)

• Source: An index of 40 leading Business Web site home pages down-load time (Keynote)

• Method:– Monday -Friday every 15 minutes between 6 am

and noon Pacific time– Around 50 agents located in metropolitan areas of

the United States.

Good News Index of Keynote Business 40 1999-2000

Better(?) NewsKeynote Index of Business 40 1998-99

Butt…Keynote Index of Consumer 40 – current

How come?

• Source: An index of 40 leading Consumer Web site home pages down-load time.

• Method:– Sunday – Saturday, every 1 hour,

between 5Am to 9Pm pacific time. – Around 50 agents in US.

• Difference: Sites + peak time

Comparison consumer vs. business

Where is the problem?

• Used to put the blame on the modem speed.• Now modems are faster• Problem is moving into the net:

– Internet service providers– Backbones– Mostly at switches

“Bandwidth like Water”?

• Claims (already 2-3 years old): – We have coming ADSL/Cable, Fiber Optics,

WDM, Tera-bits,…. – “bandwidth like water” no problem.

Answers

• They are here and still we wait…• “Free resource” paradox:

– If a resource is “free”, its doomed to be consumed!

– NAPSTER + alike: • Program to download songs/videos from other

computers (share). • 1 song = 60-100 Web pages!!• Traffic takes 30% or more in some places

(universities).

How Come Telephone is so great?

• Telephone : – old– Very uniform (all calls are alike)– Bounded (one cannot talk more than 24 hours/day)– System polices customers.

• Web:– New and dynamic – Services vary heavily (telephony, web, email, files).– User can request 100 Mbytes in a few clicks.– Little accountability (encourages greediness [pre-

fetch]).

How Come Telephone is so great? (2)

• Telephone : – Smooth traffic

• Web:– Very bursty traffic– Self-Similar / long tail – One request can generate a lot of data!!! – Need special controls!

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What is needed?

1) Separate and prioritize applications– E.g.: voice > Web > Email.

2) Users / applications should be accountable– Cannot ask the network to bring you 100 songs

“for free”.– Will the $20/ month service fee hold?

What is being done today?

• Much activity (umbrella of Quality of Service)

• Current solutions:– Partial (part of the net)– Separation and prioritization– Accountability?

• Much forward looking work

Back to Questions

• Do We Wait? YES!• Where We Wait? Here, US,…• When We wait? Consumer-time, variable!!!

• hoW much We Wait? Yet, too much• Why We Wait? Little control • Why Telephone is so great and Web is not? • Will We Wait? At least for a while..

The End

Keynote Index of Business 40 1997-1998

Detailed Comparison (in seconds)

business consumer

Yahoo .67 4.74Lycos 1.06 6.76Apple 1.21Schwab 1.30 8.46FedEx 1.54

Worst 9.8 45.47

Index (avg 40) 3.28 16.84

Detailed time measures