5.4 SMTP REQUIREMENTS SUMMARY

                                               |          | | | |S| |
                                               |          | | | |H| |F
                                               |          | | | |O|M|o
                                               |          | |S| |U|U|o
                                               |          | |H| |L|S|t
                                               |          |M|O| |D|T|n
                                               |          |U|U|M| | |o
                                               |          |S|L|A|N|N|t
                                               |          |T|D|Y|O|O|t
FEATURE                                        |SECTION   | | | |T|T|e
-----------------------------------------------|----------|-|-|-|-|-|--
                                               |          | | | | | |
RECEIVER-SMTP:                                 |          | | | | | |
  Implement VRFY                               |5.2.3     |x| | | | |
  Implement EXPN                               |5.2.3     | |x| | | |
    EXPN, VRFY configurable                    |5.2.3     | | |x| | |
  Implement SEND, SOML, SAML                   |5.2.4     | | |x| | |
  Verify HELO parameter                        |5.2.5     | | |x| | |
    Refuse message with bad HELO               |5.2.5     | | | | |x|
  Accept explicit src-route syntax in env.     |5.2.6     |x| | | | |
  Support "postmaster"                         |5.2.7     |x| | | | |
  Process RCPT when received (except lists)    |5.2.7     | | |x| | |
      Long delay of RCPT responses             |5.2.7     | | | | |x|
                                               |          | | | | | |
  Add Received: line                           |5.2.8     |x| | | | |
      Received: line include domain literal    |5.2.8     | |x| | | |
  Change previous Received: line               |5.2.8     | | | | |x|
  Pass Return-Path info (final deliv/gwy)      |5.2.8     |x| | | | |
  Support empty reverse path                   |5.2.9     |x| | | | |
  Send only official reply codes               |5.2.10    | |x| | | |
  Send text from RFC-821 when appropriate      |5.2.10    | |x| | | |
  Delete "." for transparency                  |5.2.11    |x| | | | |
  Accept and recognize self domain literal(s)  |5.2.17    |x| | | | |
                                               |          | | | | | |
  Error message about error message            |5.3.1     | | | | |x|
  Keep pending listen on SMTP port             |5.3.1.2   | |x| | | |
  Provide limit on recv concurrency            |5.3.1.2   | | |x| | |
  Wait at least 5 mins for next sender cmd     |5.3.2     | |x| | | |
  Avoidable delivery failure after "250 OK"    |5.3.3     | | | | |x|
  Send error notification msg after accept     |5.3.3     |x| | | | |
    Send using null return path                |5.3.3     |x| | | | |
    Send to envelope return path               |5.3.3     | |x| | | |
    Send to null address                       |5.3.3     | | | | |x|
    Strip off explicit src route               |5.3.3     | |x| | | |
  Minimize acceptance delay (RFC-1047)         |5.3.3     |x| | | | |
-----------------------------------------------|----------|-|-|-|-|-|--
                                               |          | | | | | |
SENDER-SMTP:                                   |          | | | | | |
  Canonicalized domain names in MAIL, RCPT     |5.2.2     |x| | | | |
  Implement SEND, SOML, SAML                   |5.2.4     | | |x| | |
  Send valid principal host name in HELO       |5.2.5     |x| | | | |
  Send explicit source route in RCPT TO:       |5.2.6     | | | |x| |
  Use only reply code to determine action      |5.2.10    |x| | | | |
  Use only high digit of reply code when poss. |5.2.10    | |x| | | |
  Add "." for transparency                     |5.2.11    |x| | | | |
                                               |          | | | | | |
  Retry messages after soft failure            |5.3.1.1   |x| | | | |
    Delay before retry                         |5.3.1.1   |x| | | | |
    Configurable retry parameters              |5.3.1.1   |x| | | | |
    Retry once per each queued dest host       |5.3.1.1   | |x| | | |
  Multiple RCPT's for same DATA                |5.3.1.1   | |x| | | |
  Support multiple concurrent transactions     |5.3.1.1   | | |x| | |
    Provide limit on concurrency               |5.3.1.1   | |x| | | |
                                               |          | | | | | |
  Timeouts on all activities                   |5.3.1     |x| | | | |
    Per-command timeouts                       |5.3.2     | |x| | | |
    Timeouts easily reconfigurable             |5.3.2     | |x| | | |
    Recommended times                          |5.3.2     | |x| | | |
  Try alternate addr's in order                |5.3.4     |x| | | | |
    Configurable limit on alternate tries      |5.3.4     | | |x| | |
    Try at least two alternates                |5.3.4     | |x| | | |
  Load-split across equal MX alternates        |5.3.4     | |x| | | |
  Use the Domain Name System                   |5.3.5     |x| | | | |
    Support MX records                         |5.3.5     |x| | | | |
    Use WKS records in MX processing           |5.2.12    | | | |x| |
-----------------------------------------------|----------|-|-|-|-|-|--
                                               |          | | | | | |
MAIL FORWARDING:                               |          | | | | | |
  Alter existing header field(s)               |5.2.6     | | | |x| |
  Implement relay function: 821/section 3.6    |5.2.6     | | |x| | |
    If not, deliver to RHS domain              |5.2.6     | |x| | | |
  Interpret 'local-part' of addr               |5.2.16    | | | | |x|
                                               |          | | | | | |
MAILING LISTS AND ALIASES                      |          | | | | | |
  Support both                                 |5.3.6     | |x| | | |
  Report mail list error to local admin.       |5.3.6     |x| | | | |
                                               |          | | | | | |
MAIL GATEWAYS:                                 |          | | | | | |
  Embed foreign mail route in local-part       |5.2.16    | | |x| | |
  Rewrite header fields when necessary         |5.3.7     | | |x| | |
  Prepend Received: line                       |5.3.7     |x| | | | |
  Change existing Received: line               |5.3.7     | | | | |x|
  Accept full RFC-822 on Internet side         |5.3.7     | |x| | | |
  Act on RFC-822 explicit source route         |5.3.7     | | |x| | |
  Send only valid RFC-822 on Internet side     |5.3.7     |x| | | | |
  Deliver error msgs to envelope addr          |5.3.7     | |x| | | |
  Set env return path from err return addr     |5.3.7     | |x| | | |
                                               |          | | | | | |
USER AGENT -- RFC-822                          |          | | | | | |
  Allow user to enter <route> address          |5.2.6     | | | |x| |
  Support RFC-1049 Content Type field          |5.2.13    | | |x| | |
  Use 4-digit years                            |5.2.14    | |x| | | |
  Generate numeric timezones                   |5.2.14    | |x| | | |
  Accept all timezones                         |5.2.14    |x| | | | |
  Use non-num timezones from RFC-822           |5.2.14    |x| | | | |
  Omit phrase before route-addr                |5.2.15    | | |x| | |
  Accept and parse dot.dec. domain literals    |5.2.17    |x| | | | |
  Accept all RFC-822 address formats           |5.2.18    |x| | | | |
  Generate invalid RFC-822 address format      |5.2.18    | | | | |x|
  Fully-qualified domain names in header       |5.2.18    |x| | | | |
  Create explicit src route in header          |5.2.19    | | | |x| |
  Accept explicit src route in header          |5.2.19    |x| | | | |
                                               |          | | | | | |
Send/recv at least 64KB messages               |5.3.8     |x| | | | |