a70a841b5dd0a6e4c7fdd68970dd496c.ppt
- Количество слайдов: 54
Matakuliah Tahun Versi : F 0662/ Web Based Accounting : 2005 : 1/0 Pertemuan 6 e. Business Security and Controls Systems 1
Learning Outcomes Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu : • Menjelaskan potensi resiko dan sistem pengendalian intern yang seharusnya ada (TIK-6) • Type threats and attacks (TIK-6) 2
Outline Materi • Materi 1 Menjelaskan potensi resiko dan sistem pengendalian intern yang seharusnya ada. • Materi 2 Type threats and attacks (TIK-6) 3
Internet Security and Electronic Payment Services 4
Internet Security Firewalls • Intranets • Extranets Secure Transmission • SSL • Digital Certificates • Digital Signatures Electronic Payments 5
Typical Computer Network Security Problems • • Network transmissions can be intercepted No proof of sender Data Integrity Non-repudiation 6
Firewalls • Are systems that establish control policies among networks. • They can permit different users to perform different operations according to their authorisation. • Two general types – Packet Level firewalls – Application Level Firewalls 7
Firewalls 8
Firewalls LAN with individual internet access Internet 9
Firewalls firewall Internet LAN With Internet access through a firewall 10
Intranets • A private network within a business used to share company information and computing resources among employees • A client-server application use TCP/IP, HTTP communication protocols and HTML publishing • May consist of interlinked local area networks, also use leased lines in the wide area network • Typically includes connections through one or more gateway computers to the outside Internet 11
Intranets 12
Extranets • Part of an enterprise's Intranet extended to users outside the company • A private network for suppliers, vendors, partners and customers rather than the general public • Uses the Internet for transmission but needs passwords for access 13
Extranets 14
Secure Transmission Who can read my E-Mail? LAN 15
Private Key Encryption 16
Public Key Encryption 17
Secure Transmission • Secure Transmission • PGP (Pretty Good Privacy) Message Integrity • SSL • Provides data authentication, message integrity, and optional client authentication. • Digital Certificate • Authentication • Digital Signature 18
Secure Transmission SSL • encrypts and then decrypts any packets of information being transmitted. • essential for sensitive corporate data or financial transactions. • May not authenticate the receiver of encrypted data. • Is currently implemented on – Netscape navigator – Internet Explorer • Uses the widely used RSA public key cryptography 19
Secure Transmission Digital Certificates • contains : – your name, – a serial number, – expiration dates, – a copy of the certificate holder's public key (used for decrypting messages and digital signatures), and – the digital signature of the certificate-issuing authority (a digital Passport) Morley E (October 12, 1999) digital certificate http: //whatis. com/ 20
Secure Transmission Digital Certificates • can be kept in registries so that authenticated users can look up other users' public keys Morley E (October 12, 1999) digital certificate http: //whatis. com/ 21
Secure Transmission 6 Without a Digital Certificate ? 22
Secure Transmission 7 With a Digital Certificate ! 23
Secure Transmission Digital Signature • authenticate the identity of the sender • the receiver can check that the message or document being sent is unchanged • can be automatically time-stamped • can be used with encrypted or normal messages • can also used be with digital certificates 24
Secure Transmission (summary) Security Technology What it does Effectiveness and Limitations Firewall Authorizes access. Filters/rejects users based on access rights on server Authorizes access, but cannot authenticate identity of user. Password based, so open to many associated problems. Digital Certificate Authenticates identity of user Certificates are vulnerable to system crash or deletion. Can be compromised if computer stolen. Cannot stop certificate and key being shared. Encryption / SSL Protects data confidentiality Only encrypts data. Does not authenticate. Encryption is compromised by using passwords or certificates. 25
Electronic and Digital Signatures • From a legal point of view, hand writing one’s name on paper has been the principle means of signature for centuries. • In today's electronic world the legal concept of a signature could include: – Digitised images of paper signatures. – Typed notations. – Letterheads or e-mail origination headers. 26
Electronic and Digital Signatures • However there is a difference between these types of electronic signatures and digital signatures. 27
Electronic Signature Definition • DEFINITION OF ELECTRONIC SIGNATURE: • Sec. 4(4). Electronic signature. -- The term "electronic signature'' means an electronic sound, symbol, or process, attached to or logically associated with a (contract or other) record and executed or adopted by a person with the intent to sign the record. 28
Electronic Transactions • The digital signature is revolutionizing ecommerce and corporate document management systems. • Legislative bodies nationwide and internationally are rewriting the definition of "signature" to include electronic signatures, and passing laws and regulations to accommodate electronic signatures on legal documents and in filings. Utah Digital Signatures Act. • Singapore : Electronic Transactions act (Act 25 of 1998). 29
Digital Signature Technology • Digital signatures are created and verified by means of cryptography. • Two different keys are generally used: – One for creating or transforming the data into a unintelligible form. – One for verifying a digital signature or returning the message to its original form. • This is usually referred to as “Asymmetric cryptosystem. ” • The keys are usually referred to as the “private key” which is only known to the signer, and the “Public Key” which is usually more widely known and used to verify the digital signature. 30
Digital Signatures • The process of creating a digital signature and verifying it accomplish the essential effects desired of a signature: • Signer Authentication – If a private key and a public key is associated with an identified signer, a digital signature by a private key effectively identifies the signer with the message • Message authentication – The process of digitally signing also identifies the matter to be signed with greater certainty and precision than paper signatures 31
Digital Signatures • Affirmative act – Creating a digital signature requires the signer to provide a private key and invoke a software function to create a digital signature. • Efficiency – The process of creating and verifying a digital signature provides a high level of assurance that the digital signature is genuinely the signer’s and is almost entirely automated or capable of automation 32
Digital Signatures and Certification Authorities • To ensure that parties using digital signatures are identified with a particular key pair, A trusted third party termed a “certification authority” is used to associate an identified person on one end of a transaction with the key pair creating the digital signature at the other end. Verisign. Society for Worldwide Interbank Funds Transfers (SWIFT). E-Club of the International Chamber of Commerce (ICC). Identrus LLC. WISe. Key S. A. 33
Digital Signatures costs and benefits • Costs. – Institutional overhead. • Cost of establishing and utilising certification authorities etc. – Product cost. • Software may be expensive. • Certification authority charges for issuing certificates. • Verification software. • Access to certificate repository. 34
Digital Signatures Costs and Benefits • Benefits. – Imposters. • Minimize risk of dealing with impostors. – Message corruption. • Minimize the risk of message tampering. – Formal legal requirements. • Legal requirements of writing, signature and an original document are satisfied. – Open systems. • Retention of a high degree of information security when information is sent over open, insecure internet channels. 35
Electronic Payment Instruments and Systems • To be attractive to consumers and businesses: – Should save money – Reduce costs in current systems – Enable consumers to spend their money more cheaply 36
Electronic Payment Instruments and Systems • Cost of Transactions – Financial Institution Teller generated $1. 07 – ATM $0. 27 – Swiping a Credit card $0. 08 - $. 015 – Dipping a smart card $0. 01 • Can squeeze as much as $1. 06 out of each of the trillions 0 f financial services transactions that occur each year • Good reason why electronic instruments and systems will change!! 37
Electronic Payments • Credit cards • SET (Secure Electronic Transactions) • Payment Services, Merchant Gateways • Micropayments (Digi. Cash, e-Cash, Net. Pay) • Mondex (Smart. Cards) 38
Electronic Payments: How credit cards work Merchant Acquirer Visa Net Issuer Duncan Unwin, QSI Payments Inc. , 2000 39
Electronic Payments: SET: Visa, Mastercard A specification which • use public-key and private-key cryptography • authenticate cardholders and merchants using digital certification • provide confidentiality of payment data – merchant does not see the credit card number 40
Electronic Payments: Payment Services, Merchant Gateways • 3 rd Party Service – Camtech, Surelink, QSI • Bank Service – CBA, ANZ, NAB, Westpac, St George Duncan Unwin, QSI Payments Inc. , 2000 41
Electronic Payments: Micropayments: • Small electronic cash payment systems – Digi. Cash, e-Cash, Net. Pay • See W 3 C for the first public working draft of the "Common Markup for Web Micropayment Systems”, at URL http: //www. w 3. org/TR/WD-Micropayment. Markup 42
Milli. Cent 43
e. Cash Website 44
Checkfree Website 45
Electronic Cash systems • Provide a direct electronic equivalent of cash – Clickshare – Mondex – Bpay 46
Mondex Website 47
Electronic Payments: Mondex (Smart Cards) 1 • Members – licensed to issue Mondex cards to cardholders and merchants. • Merchants - – Retailers, service companies and other business that enter into an agreement with Members to enable them to accept Mondex electronic cash as payment for goods and services. 48
Electronic Payments: Mondex (Smart Cards) 1 • Cardholders - – provided with a Mondex Card by a Member which enables them to pay for goods and services from Merchants and transfer money to/from other Cardholders. 49
Electronic Payments: Mondex (Smart Cards) • Home Banking - – download value from your bank account to your card. • Buying on the Internet - – buy low value goods and services on the Internet that aren't normally chargeable. • Privacy - – no record held of the transaction, – privacy normally only afforded with physical cash. – real-time verification of funds. 50
Clickshare 51
Bpay 52
Bibliography • Schneider and Perry, Electronic Commerce Chapter 7 • http: //www. course. com/downloads/sites/ec ommerce/ch 07. html • www. mondex. com 53
Summary • Mahasiswa diwajibkan membuat summary 54
a70a841b5dd0a6e4c7fdd68970dd496c.ppt