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Trusted QSL FAQ

  1. Q.  What is the difference between E-QSLs and tQSLs?
    A. A tQSL is just a special form of an E-QSL, one signed by its creator with a public key digital signature.
  2. Q.  What is wrong with
    A.  Nothing at all. The concept of a tQSL does not exclude the participation by a logbook server such as A tQSL adds a third party authentication protocol that replaces the central server as the trusted authenticator.
  3. Q.  Is a digital signature really that difficult to forge, crack or break?
    A.  Yes, it's that difficult. The only attack against a digital signature that is known to be successful requires factoring a very large number. Factoring a large number is a time consuming problem but, given enough computing power, it's not impossible. Factoring 100-digit numbers is easy with today's hardware and algorithms. The RSA-155 challenge to factor a 155-digit (512 bit) number required 37.5 CPU-years distributed across 292 computers and ultimately a supercomputer to solve. Factoring numbers of more than 200 digits is not currently feasible. The ANSI and NIST standards for digital signatures require a minimum of a 303-digit (1024-bit) number.
  4. Q.  Will a tQSL signed today continue to be trustworthy as bigger and faster computers become available?
    A.  Extrapolations have been made based on Moore's Law (computing power doubles every 18 months) and on the historical progression of the largest number factored. Both approaches give similar answers when applied to a digital signature created with today's standard commercial key length of 303-digits (1024-bits): forging such a signature will not be feasible for at least several decades to come. No one's crystal ball is perfect. A mathematical breakthrough that results in the discovery of a more efficient method for factoring large numbers clearly would alter those predictions.
  5. Q.  What is a private key?
    A.  A private key is just a very large number. In itself, it has no special meaning.
  6. Q.  What do I sign with my private key?
    A.  You sign tQSLs. You can send those tQSLs directly to your peers, submit them to an awards sponsor and deposit then in a central logbook server.
  7. Q.  What is an identity certificate (cert)?
    A.  A cert contains the user's public key, call sign and other information, plus the signature of a Certification Authority (CA) endorsing the information contained in the cert.
  8. Q.  What can I sign with my cert?
    A.  Nothing. Certs are only used for authenticating signatures. You use your private key to sign tQSLs.
  9. Q.  What is a Certification Authority (CA)?
    A.  A CA takes the user's information and public key, verifies the information and endorses the information and public key by signing them with the CA's private key creating a cert.
  10. Q.  Who are the CAs?
    A.  Currently there aren't any CAs for tQSLs. TrustedQSL will issue a "TEST" Certificate, but TrustedQSL isn't going to be in the certificate business as a CA. The ARRL will soon be issuing identity certificates for its "Logbook of the World" program.
  11. Q.  Who grants CA status?
    A.  There's no official CA status. Any person or group can act as a CA. It is up to the award sponsors who make a policy decision to accept a CA as being trustworthy for their award program.
  12. Q.  What is to stop an untrusted party from becoming a CA?
    A.  Nothing, anyone can become a CA. An award sponsor must decide to accept a CA before that CA has any trust for their award program. .
  13. Q.  What is the Public Key Infrastructure (PKI)?
    A.  A system of digital certificates, Certificate Authorities, and other registration authorities that verify and authenticate each party involved in an exchange of information.
  14. Q.  What is the "trust model"?
    A.  The trust model forms one basis for classifying different PKI architectures. A trust model defines the trusted relationships and describes the "chain of trust" from a public key that is known to be authentic through to a specific user's public key.
  15. Q.  What happens if my cert gets stolen?
    A.  . It doesn't matter. It is public information used to authenticate your signature. You can't do anything bad with it. If there is any question about a certificate being authentic, it can be authenticated with the CA's public key.
  16. Q. What happens if my secret key gets stolen?
    A.  This is a problem. You will need to contact your CA to have them revoke it.
  17. Q.  Why is signing is so slow?
    A.  Computing a digital signature involves the exponentiation of very large numbers. That is a very CPU intensive calculation that takes some time even with a fast processor. A private key operation such as signing requires performing several million operations per signature for a standard 1024-bit key. A somewhat less than bleeding edge machine such as an 800 MHz Pentium III is capable of generating 25-100 signatures per second.
  18. Q. . If digital signatures and certs are so complex why force them on users?
    A.  Digital signatures are an enabling technology. The authentication protocol provided by digital signatures keeps the E-QSL process "open" to participation by third parties. The most complex issue that a user has to deal with is the initial verification of identity. Were a central server model to be used, the initial process of identity verification would remain the same.
  19. Q.  If just a password is good enough to secure Internet banking, trading stocks, online shopping, paying taxes, etc., then why isn't a password sufficient for tQSLs?
    A. Well, there's a whole lot more at work behind the scenes in securing the typical e-commerce transaction than "just a password." In fact, an integral part of the behind the scenes action involves the same identity certificates and digital signatures used in TrustedQSL. There's absolutely no reason why tQSL implementations cannot be as equally transparent, appearing to the user to be no more complicated than "just a password."
  20. Q. Why do I need anything more than a user-id and password to log into a server and exchange tQSLs?
    A.  While you can login into a server and exchange tQSLs, you don't have to. A user-id and secret password are a way of authenticating a connection such as a login session. However, an authenticated, trustworthy connection is not necessary for sending and receiving tQSLs. It's the tQSLs themselves that are trustworthy, not the connection. That's why an inherently "untrustworthy" transport mechanism such as e-mail can be used to exchange tQSLs or to "upload" tQSLs to an award sponsor. If the server you frequent requires the use of a user-id and password, it's not because of tQSLs.
  21. Q.  I heard that the verification of my identity by a CA is going to involve paper. Heaven forbid! Why such a slow and onerous process?
    A.  The trustworthiness of a tQSL ultimately traces back to the identity verification performed by the CA. The effort expended in making sure that identification is made correctly is time well spent. To complete the initial verification process a tQSL CA must exchange some information with the user via a "trustworthy" channel. A commonly used trusted channel is the postal mail.
  22. Q.  Can't the initial enrollment with a CA be performed entirely online?
    A.   It can't, not entirely. The enrollment process can be initiated online. However, a totally online enrollment process would be readily spoofed and not trustworthy.
  23. Q.  I've enrolled in the Internet service of the XYZ Company entirely online, no postcard required. Why can't a TrustedQSL CA employ an all-electronic enrollment like a real business does?
    A.  In the enrollment process for that service you likely provided some "personal secret" that verifies your identity. Such "secrets" might be a credit card number, an account number, SSN, PIN, etc. None of those are suitable for use by a TrustedQSL CA.
  24. Q. Why must TrustedQSL be more secure then say, online shopping?
    A. QSL'ing doesn't need to be more secure than online shopping. Moreover, TrustedQSL isn't. As just one example, e-commerce transactions such as online purchases are routinely conducted over an encrypted link in order to prevent eavesdropping. tQSLs contain no sensitive or secret information. So there's no need to be employing security measures such as encryption in tQSLs.
  25. Q. Why do I need an identity certificate for QSLs when I don't need one to transact business online, to shop at for example?
    A.  Correct, you don't need an identity certificate in order to shop at Amazon. However, it is true that every time you shop at Amazon your computer receives an identity certificate and authenticates a digital signature. Whenever you log onto a secure e-commerce site such as Amazon, the secure server sends a copy of its identify certificate and a digital signature to your computer. Together, the cert and signature prove that you're really connected to a computer that, in this example, is a bona fide reresentative of Jeff Bezos' company. In part this proof is meant to reassure you that an impostor out to steal your credit card number or drain your bank account has not spoofed the connection. TrustedQSL employs the same public key digital signature technology that you've used when making online purchases, most likely without ever being aware that you were using it. The crucial difference is that in e-commerce the digital signature is used to authenticate a live connection. In TrustedQSL'ing the digital signature is used to create an archival electronic document, a tQSL, which can be authenticated at any future date.
  26. Q.  Why do I need an identity certificate to prove my identity?
    A.  You don't need a certificate to prove your identity. That's not how the identity certificate is used in the TrustedQSL process. The identity certificate is created so others can use it to verify that a tQSL that says it is from your station is authentic.
  27. Q.  Why does the CA send me a copy of the identity certificate if I don't need to use it?
    A.  For convenience and on general principles, it is after all your public key and your information. Standard practice has the sender include a copy of all the certificates in his "chain of trust" along with his tQSLs. This is a courtesy to the recipient and expedites authentication. An alternative approach would be for the CA to keep your certificate, publish it in the CA's online directory and have the recipient of your tQSLs look up your certificate online.
  28. Q.  What else can I do with a copy of my identity certificate?
    A.  You can save your identity certificate along with your private key in a standard portable format (PKCS#12). The PKCS#12 file can be read by a variety of standard applications such as e-mail programs and Internet browsers. This will allow using your private key to sign e-mail messages that you exchange with other amateurs. And other amateurs can authenticate e-mail claiming to be from you as coming from the real WA1XYZ.
  29. Q.  Who will accept my identity certificate?
    A.  TrustedQSL's goal is for your identity certificate to be accepted by other hams and by award sponsors. The broader, non-amateur radio community who have chains of trust originating in commercial CAs or national PTTs are unlikely to accept an identity certificate for WA1XYZ as being trustworthy.
  30. Q.  Why should I bother to digitally sign tQSLs
    A.  In the Spirit of Ham Radio one signs tQSLs so that your fellow hams can receive award credit for contacts they've made with you. Signing your tQSLs permits those who do care about such things, award sponsors being the prime example, to authenticate that the WA1XYZ tQSLs received from an unauthenticated intermediary did indeed originate with you, the real WA1XYZ and not some impostor.
  31. Q.  Who's an "unauthenticated intermediary?"
    A.  It can be any third party. Digital signatures permit the paradigm to shift away from security and authentication via records kept on central servers towards individual documents that can be authenticated. Just as with traditional paper QSLs, third parties are free to handle, store and forward tQSLs. It is of no concern through which hands, such as logbook servers, a tQSL may have passed prior to its being presented to an award sponsor.
  32. Q.  Can paper QSL cards have a digital signature?
    A.  Yes. It can be done with a bar code printed on the card. The information on the paper card can then be authenticated just like a tQSL.
  33. Q.  Do I need to be connected to the Internet to sign tQSLs?
    A.  No, tQSLs can be signed and sent by any means. Including but not limited to e-mail, packet radio, floppy disk, CD, even paper QSL cards.
  34. Q.  Do I need to be connected to the Internet to validate tQSLs?
    A.  No, you just need a trusted means to obtain the CAs public key.
  35. Q. What is Open Source?
    A.  Open Source is a concept in which the copyright holder wishes that the source code be accessible for anyone to use.
  36. Q. Why is Open Source important to TrustedQSL?
    A. For tQSLs to become a standard, then nothing should keep software authors from providing support for the standard. One way to encourage this is to make the source code freely available.
  37. Q.  Your efforts duplicate commercial products. Products such as Adobe Acrobat, while not free, offer digital signatures with non-repudiation today.
    A.  TrustedQSL is an open source implementation. The protocols adopted for tQSLs are the open standards supported by Microsoft, Netscape, Verisign, Adobe et al. in their products.
  38. Q.  A trusted system is also highly secure, isn't it?
    A.  There's a publication called the US Department of Defense Trusted Computer System Evaluation Criteria, commonly known as the Orange Book. Although originally written for military systems, the security classifications are now broadly used within the computer industry; terms such as C2, B1 and A1 originate in the Orange Book. Yes, a DoD trusted system is very secure. However, the only way in which the "trusted systems" described in the Orange Book are related to TrustedQSL is by the rather inopportune similarity of their names.
  39. Q. Does TrustedQSL rely upon exotic cryptographic algorithms?
    A.  No, nothing particularly exotic. TrustedQSL incorporates industry standard algorithms for creating and authenticating digital signatures. Support for these standard algorithms can already be found in most e-mail programs and Internet browsers.
  40. Q.  Doesn't TrustedQSL involve such sophisticated encryption techniques that it could never be exported outside the USA?
    A.  Absolutely not. The Bureau of Industry and Security (BIS) in the U.S. Department of Commerce administers export controls on commercial encryption products. The Export Administration Regulations (EAR) exempt from notification and review prior to export all "encryption items" having limited cryptographic functionality. Limited functionality is all that's required for TrustedQSL: generation and authentication of digital signatures. Such items may be exported without a license to any destination except the seven nations designated by the U.S. State Department as "terrorist supporting" states. Note that the export of any software to five of the "T-7" nations to which digital signature software would be controlled is subject to comprehensive embargoes administered by the U.S. Treasury Department's Office of Foreign Assets Control.
  41. Q. How about other countries, are there places where the importation or use of digital signature software is controlled?
    A. Possibly. With over 200 countries and territories having independent policy-making authority over the import, export and use of software containing cryptographic functions, it's difficult to know the answer with complete certainty. And one needs to be sure to ask the right question, as authentication cryptography that is not used for confidentiality purposes is often exempt from controls imposed on more general-purpose encryption software.
  42. Q. Do we really need to be using military grade security for QSLs?
    A.  Look, there's nothing at all like "military grade" security here. tQSLs are not secure; tQSLs are trustworthy because they can be authenticated. It's a fundamental difference. And it's not "military grade" authentication; tQSLs employ the same commercial grade authentication protocols that virtually every e-commerce site on the Web uses.
  43. Q.  Isn't the public key algorithm that's used for digital signatures patented?
    A.  Not any more. A public key algorithm commonly used for digital signatures is known as RSA (Rivest-Shamir-Adelman). The RSA algorithm was patented in the USA (Patent No. 4,405,829). However, the patent expired on 20 September 2000.
  44. Q. The system you describe is open to fraud, in that a group of users could conspire.
    A.  Sure, that could happen. As it could with paper QSL cards. Any system will not be perfect. Just ask Verisign and Microsoft.
  45. Q.  Will ARRL and other award sponsors accept tQSLs?
    A.  TrustedQSL has been selected as the authentication protocol for the ARRL's "Logbook of the World" (LOTW) project. Matching pairs of tQSLs will be acceptable for DXCC credit if both are submitted to LOTW. The ARRL has stated its goal of eventually expanding LOTW from just the DXCC program to include their other awards programs (WAS, VUCC). The RSGB (IOTA) is awaiting an E-QSL system based on public key cryptography to emerge. One could easily imagine the RSGB and other awards sponsors such as CQ Magazine (WAZ, WPX, USA-CA) will be watching the ARRL's experience with LOTW.
  46. Q.  What type of service does offer?
    A. doesn't really offer any services. We provide information about TrustedQSL systems, Open Standards and Open Source tools.
  47. Q.  Why should we trust
    A.  There is no need to trust We're not a CA. We're just advocating adoption of an open standard based on public key signatures and providing open source tools.
  48. Q.  How did TrustedQSL get its name?
    A.  What's in a name? In coming up with a name the originators of TrustedQSL were thinking in terms of trust conveyed by a digital signature, as in "the trust model." How a QSL would be trustworthy if it carried a signature that could be authenticated.
  49. Q.  You guys are doing some cool stuff. Can I be apart of it?
    A.  Sure, join the TrustedQSL reflector and let us know.
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