Elect ronic Vot ing Ronald L. Rivest MI T Laborat ory f or Comput - - PowerPoint PPT Presentation

Elect ronic Vot ing

Ronald L. Rivest MI T Laborat ory f or Comput er Science

Edison’s 1869 Vot ing Machine

I nt ended f or use in Congress; never adopt ed because it was “t oo f ast ” !

The f amous “but t erf ly ballot ”

A “dimpled chad” ???

Vot ing Technology St udy

!MI T and CalTech have begun a j oint

st udy of alt ernat ive vot ing t echnologies.

!Companion t o Cart er/ Ford commission

• n polit ical issues in vot ing syst ems.

!I nit ial work f unded by t he Carnegie

Foundat ion.

Vot ing Technologies

! Poll-sit e vot ing:

– Paper ballot (hand count ed) – Punched card (Vot omat ic; Dat avot e) – Lever Machine – Opt ical Scan – Elect ronic (DRE) – Mixed

! Remot e vot ing:

– Absent ee – Kiosk – I nt ernet vot ing

Many kinds of equipment used

Punch Card DataVote Lever Machine Paper Ballots Optical Scan Electronic Mixed

Categories

Changes f rom 1980 t o 2000

Percentage of Counties Using Different Voting Technologies

5 10 15 20 25 30 35 40 45 Paper Ballots Lever Machines VotoMatic DataVote Optically Scanned Electronic (DRE) Mixed Voting System Percentage of Counties Series1 Series2

(Chart f rom Prof . St eve Ansolabehere, MI T PoliSci)

Error Rat es by Technology

0.00% 0.50% 1.00% 1.50% 2.00% 2.50% 3.00% 3.50% DataVote Electronic (DRE) VotoMatic Optically Scanned Mixed Paper Ballot Lever Machine

Elect ronic Vot ing

!Could t he U.S. president ial elect ions

be held on t he I nt ernet ?

!Why bot her?

– I ncreased vot er convenience? – I ncreased vot er t urnout ? – I ncreased conf idence in result ? – “Because we can”?

?

Securit y Requirement s

! All eligible vot ers should be able t o vot e.

– Theref ore: can at best augment current syst em, not replace it . – May need t o close elect ronic vot ing early.

! Vot es should be privat e (anonymous).

– May be dif f icult t o ensure at home.

! Vot ers should not be able t o sell t heir vot es!

– Vot ing should be privat e and “receipt -f ree”

! I nt egrit y and verif iabilit y of result ; no

vulnerabilit y t o large-scale f raud.

The “FOO” Vot ing Scheme

!Fuj ioka, Okamot o, and Oht a

AUSCRYPT ’92, “A Pract ical Secret Vot ing Scheme f or Large Scale Elect ions”

!The basis f or t he MI T/ NTT

collaborat ive research in elect ronic vot ing.

St ruct ure of Vot ing Scheme

Administ rat or Vot er Anonymizer

1 2 3 4 5

Count er

6

The “Secure Plat f orm Problem”

I n t heory:

Alice

SKA

I n f act :

SKA

Alice

Vot ing Syst em Vot ing Syst em

The Secure Plat f orm Problem

!Because of weaknesses in modern

OS’s (Windows, UNI X), including vulnerabilit ies t o viruses and t roj an horses, we are not ready f or I nt ernet vot ing, and won’t be f or quit e a while. As t hey say, “ Don’t try this at home !! ”

Perhaps a smart phone?

!Promising, but st art ing t o look t oo

much like a deskt op PC in t erms of complexit y and consequent vulnerabilit y…

!Maybe wit h a special SI M card j ust

f or vot ing… ?

!Problems would remain: vot e-selling

(allow vot ing mult iple t imes, where last one count s!)

Some personal opinions

!More import ant t hat

no one has t heir t humb on t he scale t han having scale easy t o use or very accurat e.

!Can I convince my mom t hat syst em is

t rust wort hy?

!Physical ballot s (e.g. paper) can

provide bet t er audit t rails t han elect ronic syst ems.

More personal opinions:

! Precinct -based decisions on vot ing

t echnology has benef it s: lack of unif ormit y allows f or experiment at ion and makes large-scale f raud harder.

! Abilit y t o handle disabled vot ers will

become increasingly import ant .

! Biggest securit y problem has got t o be t he

problem of absent ee ballot s. (Not e t hat absent ee ballot s were 30% of vot e in Calif ornia, and about 20% overall.)

My f avorit e t echnology (t oday)

!Fill-in bubbles on paper ballot s.

Opt ically scan ballot s at polling sit e, bef ore ballot is deposit ed.

Harvard Yale

(THE END)