PDUR: Routing Path Communication Type & Destination Pdu Routing Type explained

PduR (stands for Pdu Router) is a BSW Service layer module in Autosar Stack, whose main functionality is to accept Pdus from a lower-layer module and deliver it to a higher-level module or vice versa.

PduR also supports routing of Pdus between different communication channels in the same ECU. 

In this post, let us try to understand these concepts in a simple way.

Routing Path Communication Types:

PduR supports two types of Routing Path Communication Types: 

• COMMUNICATION_INTERFACE routing path is used for communication of Normal communication (ex: Application) related Pdus.

• TRANSPORT_PROTOCOL routing path is used for TP (ex: Diagnsotics) communication related Pdus.

Destination PDU Routing Types:

PduR supports two types of Routing for the Destination Pdu in a Routing Path:

• API_FORWARDING routing type is used for the Routing Paths for the communication of the Pdus between Upper Layer and Lowe Layer BSW Modules.

• Typically in any project, the API_FORWARDING routing paths are used for Pdu Communication (recpetion & transmission) between COM (Service Layer) Module and the Communication Interface modules (CanIf or LinIf or SoAd or FrIf).

• In Projects where we have the usage of IpduM for Multiplexed Messages & Container Pdus, the API_FORWARDING routing paths are also used for Pdu Communication between COM & IpduM and in between IpduM & Communication Interface modules.

• GATEWAY_ROUTING routing type is used for the Routing Paths for the communication of the Pdus between different communication channels in the same ECU for gatewaying functionality.

• Typically in any project, the GATEWAY_ROUTING routing paths are used for Pdu Communication (recpetion & transmission) between different Communication Interface modules (CanIf or LinIf or SoAd or FrIf).

• In Projects where we have more than 1 communication channels of the same Communication type (CAN or LIN or Ethernet or Flexray), GATEWAY_ROUTING routing paths are also used for Pdu Communication (recpetion & transmission) between different Channels of the same communication type (Ex: CanIf (Channel1) <--> CanIf (Channel2)).

Similarly PduR Routing paths for Diagnostics services will also support API_FORWARDING or GATEWAY_ROUTING as Destination Pdu Routing type:

• Typically in any project, the API_FORWARDING routing paths are used for Tp Pdu Communication (recpetion & transmission) between DCM (Service Layer) Module and the Communication Tp modules (CanTp or LinTp or DoIP or FlexrayTp).

• Also in any project, the GATEWAY_ROUTING routing paths are used for Tp Pdu Communication (recpetion & transmission) between different Communication Tp modules (CanTp or LinTp or DoIP or FlexrayTp).

• In Projects where we have more than 1 communication channels of the same Communication type (CAN or LIN or Ethernet or Flexray), GATEWAY_ROUTING routing paths are also used for Pdu Communication (recpetion & transmission) between different Channels of the same communication type (Ex: CanTp (Channel1) <--> CanTp (Channel2)).