1. Securing Transactions: Protocols and Politics D. Crocker Brandenberg Consulting +1 408 246 8253 dcrocker@brandenburg.com D. Crocker Brandenberg Consulting +1 408 246 8253 dcrocker@brandenburg.com b b b b b b b b

2. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Brandenburg Consulting  Product & service / planning & design  Technical 4 Large-scale systems 4 Internet & interoperability 4 Operations 4 Security 4 Protocols (email, transport, commerce)  Internet development since 1972  Chair, Silicon Valley - Public Access Link

3. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Secure transactions  Doing business on the Internet  Object- vs. Transport- security  Payment protocols  Standards work

4. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Internet for commerce?  Strong pressures emerging 4 Businesses now online 4 Reduced access costs 4 Global “reach”

5. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b A global Internet  Scaling 4 A chicken in every pot!  Security 4 Military vs. commercial vs. personal  Management  4 Interconnection  interoperability  4 Sometimes  always

6. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Styles of use  Receiver pull 4 Interactive sessions 4 Individual, foreground refinement  Sender push 4 Messaging 4 Bulk, background distribution (Mark Smith, Intel)

7. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b To be on the Internet  Full (core) 4 Permanent, visible, native  Direct (consumer) 4 Native  Client 4 User runs Internet applications  Mediated 4 Provider runs applications for user  Messaging 4 Surprisingly useful

8. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b What is business?  R&D 4 Search, browse 4 Test 4 Coordinate  Support 4 Discuss 4 Info push  Marketing 4 Targeted info push 4 Survey  Sales 4 Negotiate 4 Order, bill, pay 4 Deliver

9. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Where to put functions?  Core vs. edges 4 Place it in the core Can’t be used until all of the pieces between users adopt it 4 Place it at the edges Useful as soon as adopted by two, consenting hosts

10. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Where to put security... My object Object Transport Secure My object FTP EMail Web Secure My object Secure My object EMail My object Web Security Web Server MTAMTA MTAMTA EMail Security

11. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Transport security IPSEC IP-level labeling Kerberos (MIT) Third-party service S-KEY (Bellcore) Pairwise login S-HTTP (EIT) Negotiate specifical object wrapper security SSL (Netscape) Client-server transport link STT (Microsoft) (TBD)

12. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Object security  MOSS (was: PEM) 4 MIME Object Security Service - IETF 4 RSA + DES 4 Global, formal key certification hierarchy  PGP 4 Pretty Good Privacy - Phil Zimmerman 4 RSA + IDEA 4 Informal, personal, direct certification  S/MIME 4 Secure MIME - RSA & Consortium

13. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Basic algorithms MsgMsgMsgMsg MsgMsg Msg Hash Msg Hash ++ Ÿ Ÿ + + Key PRIV-ORIG Digital Signatur e Digital + Key DATA Ÿ Ÿ EncryptDataEncryptData Msg Hash Msg Hash + Key DATA + Key PUB-RECIP Key PUB-RECIP IntegrityAuthentication (sign) Privacy (seal) ŸŸ EncryptKeyEncryptKey When do you need each?...not always!

14. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b EDI over Internet  Multiple EDI transports already 4 Internet is one more  EDI/MIME, proposed standard 4 Regular EDI objects, encapsulated in MIME 4 Use MIME-based security

15. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Payment system model Buyer Merchant Issuing Bank Acquiring Bank Clearing House 16+4 (M. Rose, FV )

16. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Payment system issues  Transaction category “card not present” 4 For all bankcard approaches for Internet  Issues 4 Knowing buyer/merchant authorized 4 Avoiding third-party interception 4 Interchange, assessment, fees 4 Retrievals, chargebacks, etc. Risk management Risk management

17. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Payment system efforts Commercenet www.commerce.net First Virtual Holdings www.fv.com CyberCash www.cybercash.com Open Market www.openmarket.com NetMarket www.netmarket.com Netscape www.netscape.com DigiCash www.digicash.com

18. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Scheme “Clear” ClearingHouse Buyer Merchant 16+4 in the clear! 16+4 Just trust the net... Easy to capture and replay.

19. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Scheme “ID” ClearingHouse Buyer Merchant 16+4 ID ID 16+4 Still Still trust the net, until the next statement... Easy to capture and replay.

20. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Scheme “ID confirm” ClearingHouse Buyer 16+4 ID ID Confirm ID Merchant Each transaction confirmed. Requires mildly safe user account.

21. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Scheme “Secure link” ClearingHouse Buyer Merchant Encrypted16+4 16+4 Same a telephone, but encrypt over Internet. Merchant gets number. Is merchant safe??

22. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Scheme “Mediated” ClearingHouse Buyer Merchant Encrypted16+4 Encrypted16+4 Only banks sees data in clear. Limited points of attack.

23. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b The standards debate Open IP labeling Session Security S-HTTP (sort of) MOSS Proprietary SSL STT PGP (sort of) S/MIME

24. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Freezing out competition  Non-interoperability mine 4 Do it because it’s mine! 4 Customer lock-in through proprietary extensions  Half-hearted integration 4 Specialized protocols for each and every need

25. © 1995 D. Crocker, Brandenburg Consulting b b b b b b b b Is there hope?  Vendor initiatives 4 Market lead  Folded into public standards 4 Open access 4 Open enhancement It all depends on market demand. You are the market; start demanding!