background image
Tech Note #36: Introduction to the Alarm Clock Protocol (ACP)
©
1998 Bionic Buffalo Corporation; All Rights Reserved.
                  12 June 1998
http://www.tatanka.com
Page 
3 of 8
tagged fields
request identifiers
message segments
A new request is created when a client sends a message containing a new request identifier.
Each request identifier has a finite lifetime. The lifetime of a request identifier is defined by the
client, and may be extended later by the client. Clients which power down or which otherwise
separate from the network might leave out-standing requests, but eventually those requests will
expire.
Each request specifies an action to be performed by the server. The available services are listed
in the next section.
A message segment (associated with a specific request identifier) is identified as a request, a
response, or a notice.
•
 
A request is used to ask the server to perform a certain action. Note that a subsequent,
related request uses a separate request identifier. For example, a request for an Alarm
Single might have identifier 1234, while a request to Cancel the first request might have
identifier 5678.
•
 
A response optionally may be sent in response to any request. It may contain requested
information, status, or exception codes. If the request involves a delay, then a response is
sent after the requested service is scheduled, otherwise the response is sent after the service
is performed.
•
 
A notice is a message sent by the server after an intentional delay. For example, if an Alarm
Single is requested after an interval of 10 seconds, then the response would be sent
immediately and the notice 10 seconds later.