The S7 Protocol (RFC 1006) enables the connection of S7 automation devices with any communication partner. It provides direct access to the S7 user memory without changes in the user application itself.
As shown in the figure below, the S7 Protocol (RFC 1006) supports a variety of different transportation methods.For the usage of TCP/IP, only a communication unit (CP) for Ethernet connection or alternatively an onboard Ethernet interface that supports ISOonTCP (RFC1006) must be available.
In comparison to Simatic Fetch/Write, the S7 Protocol (RFC 1006) allows the addressing of all internal on the PLC side, i.e. no limitation on the data blocks (DB). Depending on the PLC only small or no configuration changes at all must be made to support the S7 Protocol (RFC 1006).
The SIMATIC® S7 series supports the protocol ISO-on-TCP natively in passive mode, i.e. it operates as a server and accepts client connections.
ISO-on-TCP (RFC 1006) TCP (RFC 793)
IP (RFC 791)
IP (RFC 894)
Ethernet (IEEE 802.3)
Available Protocol Stacks
S7 Protocol, Client
Universal protocol converter for highest degree of flexibility