HP UX 11i v2 Networking Software manual Connection-mode Service Primitives, Dlhpinforeq

Models: UX 11i v2 Networking Software

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DLPI Primitives

Connection-mode Service Primitives

Connection-mode Service Primitives

This section describes the service primitives that support the connection-mode service of the data link layer. These primitives support the establishment of connections, connection-mode data transfer, and connection release services.

In the connection establishment model, the calling DLS user initiates a request for a connection, and the called DLS user receives each request and either accepts or rejects it. In the simplest form, the called DLS user is passed a connect indication and the DLS provider holds any subsequent indications until a response for the current outstanding indication is received. At most one connect indication is outstanding at any time.

DLPI also enables a called DLS user to multi-thread connect indications and responses. The DLS provider will pass all connect indications to the called DLS user (up to some pre-established limit as set by DL_BIND_REQ and DL_BIND_ACK). The called DLS user may then respond to the requests in any order.

To support multi-threading, a correlation value is needed to associate responses with the appropriate connect indication. A correlation value is contained in each DL_CONNECT_IND, and the DLS user must use this value in the DL_CONNECT_RES or DL_DISCONNECT_REQ primitive used to accept or reject the connect request.

Once a connection has been accepted or rejected, the correlation value has no meaning to a DLS user. The DLS provider may reuse the correlation value in another DL_CONNECT_IND.

Connection-Oriented DLPI Extensions

These primitives are only valid on connection-oriented DLPI STREAMS. Connection-oriented DLPI streams are those on which a DL_BIND_REQ with dl_service_mode set to DL_CODLS has been done.

DL_HP_INFO_REQ

Requests the DLS provider to provide information on the state of the connection on a DLPI stream.

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Chapter 2

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HP UX 11i v2 Networking Software Connection-mode Service Primitives, Connection-Oriented Dlpi Extensions, Dlhpinforeq