"Fossies" - the Fresh Open Source Software Archive

Member "apg-2.2.3/doc/rfc0972.txt" (7 Aug 2003, 3776 Bytes) of package /linux/privat/old/apg-2.2.3.tar.gz:

    1 
    2 
    3 Network Working Group                                          F. Wancho
    4 Request for Comments: 972                                           WSMR
    5                                                             January 1986
    6 
    7                       Password Generator Protocol
    8 
    9 
   10 STATUS OF THIS MEMO
   11 
   12    This RFC specifies a standard for the ARPA Internet community.  Hosts
   13    on the ARPA Internet that choose to implement a Password Generator
   14    Protocol (PWDGEN) are expected to adopt and implement this standard.
   15    Distribution of this memo is unlimited.
   16 
   17 BACKGROUND
   18 
   19    Many security-conscious host administrators are becoming increasingly
   20    aware that user-selected login passwords are too easy to guess for
   21    even casual penetration attempts.  Some sites have implemented
   22    dictionary lookup techniques in their password programs to prevent
   23    ordinary words from being used.  Others have implemented some variant
   24    of a randomly generated password with mixed success.  The problem
   25    arises from the fact that such passwords are difficult to remember
   26    because they cannot be pronounced or are based on a relatively short
   27    cycle pseudo-random number generator.
   28 
   29    A version of the PWDGEN algorithm briefly described below has been in
   30    use for several years at a small number of sites in the Internet.
   31    Interest has recently been expressed at porting this algorithm to
   32    other sites.  However, the relatively short cycle and the resulting
   33    randomness of the pseudo-random number generator available on these
   34    sites tends to interfere with the intended result of minimizing the
   35    potential duplication of passwords both within a site and across
   36    sites when a user has access to more than one site.
   37 
   38    The PWDGEN Service described herein provides a means for sites to
   39    offer a list of possible passwords for the user to choose one from
   40    the first set, or optionally select from another set.  With more than
   41    one site offering this service, it is then possible to randomly
   42    select which site to use and have multiple fallback sites should that
   43    site be unavailable.
   44 
   45    Description
   46 
   47       The PWDGEN Service provides a set of six randomly generated
   48       eight-character CRLF-delimited "words" with a reasonable level of
   49       pronounceability, using a multi-level algorithm.  An
   50       implementation of the algorithm is available in FORTRAN-77 for
   51       examination and possible implementation by system administrators
   52       only.
   53 
   54 
   55 
   56 Wancho                                                          [Page 1]
   57 
   58 
   59 
   60 RFC 972                                                     January 1986
   61 Password Generator Protocol
   62 
   63 
   64       The uniqueness of the generated words is highly dependent on the
   65       randomness of the initial seed value used.  The availability of a
   66       single system-wide seed, updated after each access is highly
   67       desireable.  Seeds based on a time-of-day clock are unacceptable.
   68       Seed values should be stored as values in excess of 32 bits for
   69       best performance.
   70 
   71    TCP Based PWDGEN Service
   72 
   73       One PWDGEN service is defined as a connection based application on
   74       TCP.  A server listens for TCP connections on TCP port 129.  Once
   75       a connection is established, the six CRLF-delimited words are
   76       generated and sent to the caller, and the connection is closed by
   77       the server. No dialog is used or required.
   78 
   79    UDP Based PWDGEN Service
   80 
   81       Another possible PWDGEN service is defined as a datagram based
   82       application on UDP.  A server listens for UDP datagrams on UDP
   83       port 129.  When a datagram is received, the six CRLF-delimited
   84       words are sent back in an answering datagram.
   85 
   86 
   87 
   88 
   89 
   90 
   91 
   92 
   93 
   94 
   95 
   96 
   97 
   98 
   99 
  100 
  101 
  102 
  103 
  104 
  105 
  106 
  107 
  108 
  109 
  110 
  111 
  112 
  113 Wancho                                                          [Page 2]
  114