SNPP Technical Specifications:

Response Code Details

Code 214 - Multi-line "help/info" message This code prefixes a line of response information (such as in response to the HELP command). It should be terminated with a "250 OK" message. This code is used when the response will take more than one line to display.

Code 218 - Single-line "help/info" message This code prefixes a single line of response information (such as the request for a single database entry). Unlike the 214 series, it has no "250" series terminator.

Code 250 - Successful Transaction This code is a general positive acknowledgment from the server indicating that a command was successfully processed. Additionally, code 250 can appear at the end of the response to a HELP command (214 series commands--discussed below).

Code 421 - Fatal Error, Connection Terminated This code is displayed just prior to the SNPP server terminating a connection with a client for errors. Such a connection termination may occur at any time and for any reason (administrative or technical).

Code 500 - Command Not Implemented This code is a "fail but continue code" that appears when an illegal command is entered.

Codes 550 and 554 - Transaction Failed, but Continue These codes indicate a failed command, but the session is allowed to continue. A 550 code should be used to indicate a more "administrative" failure (such as an invalid pager ID, or illegal parameter), while a 554 series indicates a more technical reason (such as a gateway down or equipment failure). In addition to the specified failure codes, additional 550 and 554 failures may be specified as necessary to allow for greater flexibility.

Code 552 - Maximum Entries Exceeded This code is in response to the entry of the "n+1" item when the server only permits "n" items in a category. As an example, the client would expect to see this message when trying to enter the 6th PAGEr command when the terminal only supported 5.

More on SNPP...