Pki & Personal Digital Certificates, The Key To Securing Sensitive Electronic Communications
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Pki & Personal Digital Certificates, The Key To Securing Sensitive Electronic Communications






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Pki & Personal Digital Certificates, The Key To Securing Sensitive Electronic Communications Pki & Personal Digital Certificates, The Key To Securing Sensitive Electronic Communications Presentation Transcript

  • PKI & Personal Digital Certificates, The Key to Securing Sensitive Electronic CommunicationsDecember 2, 2010 Nicholas Davis
  • Agenda• Introduction• We will eat• We will watch movies• We will find an error in the textbook• We will learn• We will chat• We will have fun
  • Twix• Twix is a candy bar made by Mars, Inc., consisting of a biscuit finger, topped with caramel and coated in milk chocolate. Being somewhat smaller in width than other confectionery bars, Twix bars are typically packaged in pairs. Twix was first produced in the UK in 1967, and introduced in the United States in 1979 View slide
  • OverviewWhy is electronic privacy such a hottopic these days?What is a digital certificate?What is PKI?Why are these technologies important?Trusted Root AuthoritiesUsing digital certificates for email encryptionKey Escrow, the double edged swordIntegrating digital certificates into email forSecurityHow is PKI related to SSL?Using certificates for code signing of softwareReal world issues with PKIDiscussion View slide
  • Whay is Electronic PrivacySuch a Hot Topic Today? • Evolution of the Internet, commerce, banking, healthcare • Dependence on Email • Government regulations, SOX, HIPAA, GLB, PCI, FERPA • Public Image • Business warehousing • Industrial Espionage • The government
  • The Topic is More Interesting When It Affects You!
  • Intercepting Your Electronic Communications
  • Discussion Topic One• Do you think the threat of Email eavesdropping is real?• What about the government’s argument about Email being like a “postcard?”• Should Target be allowed to look at Walmart emails on a public network?• Are you angry now, or just afraid?• Who has the responsibility in this situation?
  • What is a Digital Certificate?
  • Digital Certificates Continued Digital Certificate Electronic Passport Good for authentication Good non-repudiation Proof of authorship Proof of non-altered content Encryption! Better than username - password
  • What is in a Certificate?
  • Public and Private Keys The digital certificate has two parts, a PUBLIC key and a PRIVATE key The Public Key is distributed to everyone The Private Key is held very closely And NEVER shared Public Key is used for encryption and verification of a digital signature Private Key is used for Digital signing and decryption
  • Public Key Cryptography
  • Getting Someone’s Public Key The Public Key must be shared to be Useful It can be included as part of your Email signature It can be looked up in an LDAP Directory Can you think of the advantages and disadvantages of each method?
  • Who Could This Public Key Possibly Belong To?
  • What is PKI?• PKI is an acronym for Public Key Infrastructure• It is the system which manages and controls the lifecycle of digital certificates• The PKI has many features
  • What Is In a PKI? • Credentialing of individuals • Generating certificates • Distributing certificates • Keeping copies of certificates • Reissuing certificates • Revoking certificates • Renews certificates
  • Credentialing• Non technical, but the most important part of a PKI!• A certificate is only as trustworthy as the underlying credentialing and management system• Certificate Policies and Certificate Practices Statement
  • Certificate Generation and Storage • How do you know who you are dealing with in the generation process? • Where you keep the certificate is important
  • Distributing Certificates• Can be done remotely – benefits and drawbacks• Can be done face to face – benefits and drawbacks
  • Keeping Copies – Key Escrow • Benefit – Available in case of emergency • Drawback – Can be stolen • Compromise is the best! • Use Audit Trails, separation of duties and good accounting controls for key escrow
  • Certificate Renewal• Just like your passport, digital certificates expire• This is for the safety of the organization and those who do business with it• Short lifetime – more assurance of validity but a pain to renew• Long lifetime – less assurance of validity, but easier to manage• Can be renewed with same keypair or new keypair depending on escrow situation
  • Expiration• A rare moment for me…I get to point out and error in the textbook! (Page 418)• A message signed with an expired private key will show as invalid to the recipient• However, a private key can ALWAYS be used to decrypt a message, even an expired private key.• Nobody is perfect, forgive the textbook author!
  • Revocation• Just like Stefan Wahe’s dirving license, it can (and should be) be revoked prior to expiration• CRL – Certificate Revocation List• OCSP – Online Certificate Status Protocol• Both are real time• In practice, both are rarely used
  • Recovery• No escrow = no luck• But with escrow it must be easy, right? !!NOT!!• Proving identity• Getting copy from escrow• Secure delivery to recipient• Complex, tempting to cut corners, but resist temptation!• The book’s idea is even more complex!
  • Trusted Root Authorities• A certificate issuer recognized by all computers around the globe• Root certificates are stored in the computer’s central certificate store• Requires a stringent audit and a lot of money!
  • It Is All About Trust
  • Using Certificates to Secure Email • Best use for certificates, in my opinion • Digital certificate provides proof that the email did indeed come from the purported sender • Public key enables encryption and ensures that the message can only be read by the intended recipient
  • Secure Email is Called S/MIME • S/MIME = Secure Multipurpose Mail Extensions • S/MIME is the industry standard, not a point solution, unique to a specific vendor
  • Digital Signing of Email • Proves that the email came from you • Invalidates plausible denial • Proves through a checksum that the contents of the email were not altered while in transit • Provides a mechanism to distribute your public key
  • Digital Signatures Do Not Prove Whena Message or Document Was Signed You need a neutral third party time stamping service, similar to how hostages often have their pictures taken in front of a newspaper to prove they are still alive!
  • Send Me a Signed Email, Please, I Need Your Public Key
  • Using a Digital Signature for Email Signing Provides proof that the email came from the purported sender…Is this email really from Vice President Cheney? Provides proof that the contents of the email have not been altered from the original form…Should we really invade Mexico?
  • A Digital Signature Can Be Invalid For Many Reasons
  • Why Is Authenticating the Sender So Important?
  • What if This Happens at MadisonCollege? Could cause harm in a critical situation Case Scenario Multiple hoax emails sent with Chancellor’s name and email. When real crisis arrives, people might not believe the warning. It is all about trust!
  • Digital Signing Summary• Provides proof of the author• Testifies to message integrity• Valuable for both individual or mass email• Supported by most email clients….Remember the 80-20 rule..Perfect in the enemy of good!
  • What Encryption DoesEncrypting data with adigital certificateSecures it end to end.• While in transit• Across the network• While sitting on email servers• While in storage• On your desktop computer• On your laptop computer• On a server
  • Encryption Protects the Data At Rest and In Transit Physical theft from office Physical theft from airport Virtual theft over the network
  • Why Encryption is Important • Keeps private information private • HIPAA, FERPA, SOX, GLB compliance • Proprietary research • Human Resource issues • Legal Issues • PR Issues • Industrial Espionage • Over-intrusive Government • You never know who is listening and watching!
  • What does it actually look like in practice? -Sending-
  • What does it actually look like inpractice (unlocking my private key) -receiving-
  • What does it actually look like in practice? -receiving- (decrypted)
  • Digitally signed and verified; Encrypted
  • What does it look like in practice? -receiving- (intercepted)
  • Intercepting the Data in Transit • How might encrypted email be a security threat to your organization?
  • Digital Certificates For Machines Too • SSL – Secure Socket Layer • Protection of data in transit • Protection of data at rest • Where is the greater threat? • Our certs protect both!
  • Benefits of Using Digital CertificatesProvide global assurance of your identity,both internally and externally to the organizationProvide assurance of message authenticityand data integrityKeeps private information private, end toend, while in transit and storageYou don’t need to have a digital certificateTo verify someone else’s digital signatureCan be used for individual or generic mailaccounts.
  • The Telephone AnalogyWhen thetelephone wasinvented, it washard to sell.It needed toreach criticalmass and theneveryone wantedone.
  • That All Sounds Great in Theory, But Do I Really Need It? • The world seems to get along just fine without digital certificates… • Oh, really? • Let’s talk about some recent stories
  • We Have Internal Threats Too @ UW-Madison!
  • How Do Users Feel About the Technology? • Ease of use • Challenges • Changes in how they do their daily work • Benefits • Drawbacks
  • It Really Is Up To You!• Digital certificates / PKI is not hard to implement• It provides end to end security of sensitive communications• It is comprehensive, not a mix of point solutions• You are the leaders of tomorrow, make your choices count by pushing for secure electronic communications!
  • Traditional Written Signatures 54
  • Signatures - Evidence• What is a signature?• A signature is not part of the substance of a transaction, but rather, it represents an understanding, acceptance or indication of agreement• Evidence: A signature authenticates a person by linking the signer with the signed document. When the signer makes a mark in a distinctive manner, the writing becomes attributable to the signer.• Example: Credit card receipt
  • Signatures – The Three Part Process • Ceremony, Approval and Commitment
  • Signatures – The Three Part Process• Ceremony:• The act of signing a document calls to the signers attention the significance of the signers act, and thereby helps prevent reckless or careless commitments
  • Signatures – The ThreePart Process• Approval:• In certain contexts defined by law or custom, a signature expresses the signers approval or authorization of the writing, or the signers intention that it have legal effect
  • Signatures – The ThreePart Process• Commitment:• A signature on a written document often imparts a sense of clarity and finality to the transaction
  • Signatures• Traditional signatures put the cart before the horse!• How can you be certain that a mortgage application with Nicholas Davis’s signature was indeed signed by Nicholas Davis?• As trusting people, we generally accept a written signature at face value
  • Signatures• Trust – When the going gets tough, scoundrels can emerge, to challenge the signature on a document• Verification against other documents – Assumes that you have access to other signed documents and assumes that signatures on those documents were not forged
  • Signature• Before a signature can be trusted, we must have proof that the signature does truly belong to the signer• This is not as easy at it sounds…..
  • Signatures – CredentialingProcess• Credentialing – An initial method of attestation to the truth of certain stated facts, such as identity.• Example: Government photo ID, address verification or proof of your SSN#, are all attestation methods used to credential people
  • Signatures – AuthenticationProcess• Authentication – The process of verifying that a person is in fact who they claim to be• Example: Showing your driver’s license to the guard at the front desk authenticates me as genuinely being Nicholas Davis
  • Signatures – AuthorizationProcess• Authorization -- The granting of power or authority to someone, to do something specific• Example: The information system authorizes Nicholas Davis the rights to view certain files
  • Signatures -- Trust • In order for a signature to be relied upon and trusted for authorization of a transaction, the individual presenting the signature must first be credentialed and then authenticated, prior to allowing them to authorize a transaction • A three step process: Credentialing, Authentication, Authorization • In the world of written signatures, organizations rarely credential or authenticate people
  • Signatures -- Trust• A written signature, provided without a solid credentialing and authentication process, can make an organization and its customers vulnerable to fraudulent transactions• To further protect the organization and our customers from fraud, we look to information technology and the use of digital signatures…..
  • Digital Signatures vs. Written Signatures• A digital signature provides proof of:• Verified identity of the signer• Document integrity (The document has not been altered since it was digitally signed)• Non-repudiation (the signer can’t deny signing the document, as it was done with their digital certificate, which only they had access to)• A written signature provides proof of:• Unverified identity of the signer• Which type of signature provides a higher degree of trust?
  • Digital Signatures – A Note About Identity Theft • As the Internet and E-Commerce continue to evolve and grow, it is important to understand what this change in business environment means • More and more traditional business processes are being converted to online applications • It is harder to impersonate someone in person than it is over the Internet
  • Digital Signatures• Written signatures may be acceptable in person, but are impractical and risky when used in an online transaction because, we no longer can associate a face with the signature• If our processes are going digital, so must our signatures!
  • Digital Signatures vs Electronic Signatures • “Electronic signature” and “Digital signature” are not synonymous. • An electronic signature can be a symbol, sound, or process used to sign a document or transaction. • A digital signature, on the other hand, is a secure electronic signature which uses encryption to authenticate the entity who signed the document, encapsulate document contents to protect from unauthorized alteration and provide proof of non-repudiation
  • Digital Signatures vsElectronic Signatures• A digital signature is a form of an electronic signature, but an electronic signature is not necessarily a digital signature.• Electronic signatures at best provide only questionable proof of identity, and do not provide proof of information/message integrity or non-repudiation
  • How Can I Help You?ndavis1@wisc.eduTel. 608-347-2486