Introduction to DLPI

DLPI Services

Raw-mode Data Transfer

The raw-mode data transfer service provides the same service as the connectionless data transfer service. The only difference is that the raw- mode DLS user builds the complete MAC and LLC headers prior to data transfer, whereas the connectionless-mode DLS user merely specifies the peer DLS user and the DLS provider then builds the complete MAC and LLC headers before transferring the packet.

The DL_HP_RAWDATA_REQ conveys one DLSDU to the DLS provider. The DL_HP_RAWDATA_IND conveys one DLSDU to the DLS user. The normal flow of messages is illustrated in Figure 1-29.

Figure 1-29 Message Flow: Raw Data Transfer

DL_HP_RAWDATA request

DL_HP_RAWDATA indication

Error Reporting Service

The raw-mode error reporting service provides the same services as the connectionless-mode error reporting services. However, the DL_ERROR_ACK primitive is used in place of the DL_UDERROR primitive to report all error conditions in raw-mode.

Figure 1-30 Raw-Mode Error Reporting

DL_ERROR_ACK indication

XID and TEST Service

The XID and TEST service enables the DLS user to issue an XID or TEST request to the DLS provider. On receiving a response for the XID or TEST frame transmitted to the peer DLS provider, the DLS provider sends up an XIS or TEST confirmation primitive to the DLS user. On receiving an XID or TEST frame from the peer DLS provider, the local

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HP UX 11i v2 Networking Software manual Raw-mode Data Transfer, XID and Test Service