IEEE 1701-2011 pdf free.IEEE Standard for Optical Port Communication Protocol to Complement the Utility Industry End Device Data Tables.
Following the guidelines established by the OSI seven-layer model, the protocol described in this standard provides the following three functions:
a)Establishment and modification of the communication channel
b) Transport of information to and from the C12.18 Device
c) Orderly closure of the communication channel when communications are complete
Three layers are used to provide these communication capabilities. These arc the Physical, Data Link. and Application layers.
With the default conditions established by this standard, the communication channel is considered always available once the physical connection has been completed. The required Identification Service is used to obtain the protocol version and revision in use by the C 12.18 Device. Certain communication parameters may be modified through the use of the Negotiate Service in the Application Layer. The Negotiate Service is optional and, if not implemented in the Cl 2.18 Device or not used during actual communications, the communication channel parameters shall remain at the default settings specified by this standard, Device implementers are strongly encouraged to implement this service.
Once the Cl2.lX Device identification and communication parameters have been established, the Application Layer provides Logon, Security, and Logoff services for session activation, access control and deactivation, Read and Write services fr issuing data transmission requests. a Terminate service for shutdown of the communication channel, and a response structure that provides information regarding the success or failure of the rvice requests.
An example of a typical communications session would consist of the following services with appropriate
responses. in the order listed: ldentiticaiion, Negotiate, Logon, Security, Reads or Writes, Logoff and
Terminate. Note that this brief example does not detail the packet structure or other aspects of the protocol.
Annex A and Annex 13 contain examples with more detail.
4.1 Order of transmission
Within the syntax definitions, multiple parameters shall be transmitted in the order as shown, from left to right.
Service parameters in all layers within the protocol definition are transmitted most significant byte first. The order of transmission of data field parameters within Tables is dictated by the Table structure.
Bytes are transmitted in frames. Each frame consists of a start bit, followed by <byte>, and ending with a stop hit. The start bit is transmitted first.
Bits within each byte are transmitted least significant bit first.IEEE 1701 pdf download.