1. Communication protocols
Application Process
Network independent Interface
ACSI Abstract Comm. Service Interface
SCSM 1
SCSM 2
SCSM n
Specific Comm. Service Mapping
Specific Interface
The ACSI is a client - server oriented approach. The basic idea is to create an abstract interface between the communication and the application.
The SCSM is the adapter between the application requirements and the features of the selected communication stack. The implementation of the SCSM is the principal task to be done.
The goal of this approach is, to reach independence between application and communication. This with the goal to protect investments in application development so that the application software may be reused in future systems with new communication technology.
AL 1
AL 2
AL n
Application Layer 7
Layer 1..6

2. Communication concepts
GOOSE Message Sampled Values
multicast
Peer to peer communication; time critical
Physical Device
Physical Device
ACSI Client
ACSI Server
Data
reports
req / rsp
Client / Server communication
Data
Data
Applications of "peer-to-peer" communication
tripping of circuit breakers: short information that needs to be transmitted with a low probability of loss within a few milliseconds
transmission of sampled values from instrumental transformers: high amount of data, to be transmitted within a few milliseconds, loss of data needs to be detected
Application
Physical Device
ACSI Server
Data
Data
Data
Physical Device
Application
Application

3. Client / Server Services
Communication stack
Application
ACSI
GOOSE
Samples
Client / Server Services
MMS
ASN.1
ISO Session
RFC 1006
TCP IP
EthType
EthType
EthType
Ethernet II
Priority tagging 802.1p/802.1Q

4. Interface model 7 9 61850-8-1 1 6 1 6 3 8 3 61850-9-1 4 5 61850-9-2 4
Technical Services 7
Station Level 9
Function A
Function B 1 6 1 6
Bay Level
Bay Level 3 8 3
Protection
Control
Protection
Control 4 5 4 5
HV Equipment
HV Equipment

5. System overview
IEC
IEC x