DICOM PS3.18 2019c - Web Services

8.10.4 Open Notification Connection Transaction

This transaction creates a connection between the user agent and the origin server over which the origin server can send Event Reports to the user agent.

Note

An origin server might play the role of a user agent when communicating with another origin-server.

The connection uses the WebSocket protocol. The connection can use the same TCP port as the HTTP connection, but they are separate connections.

See [RFC6455] for details of the WebSocket protocol.

8.10.4.1 Request

There is more than one way to establish a WebSocket connection. An origin server that conforms to [RFC6455] will at least support requests to open a WebSocket over an HTTP connection that have the following syntax:

GET SP / SP version CRLF
Host: host CRLF
Upgrade: "WebSocket" CRLF
Connection: "Upgrade" CRLF
Origin: url CRLF
Sec-WebSocket-Key: nonce CRLF
Sec-WebSocket-Protocol: protocols CRLF
Sec-WebSocket-Version: "13" CRLF
*(<header-field> CRLF)
CRLF

The origin server may support other methods of opening a WebSocket connection, which should be included in the Conformance Statement and the Retrieve Capabilities response.

8.10.4.1.1 Target Resources

The Target Resource is an origin server implementing a DICOM RESTful Service.

8.10.4.1.2 Query Parameters

This transaction has no query parameters.

8.10.4.1.3 Request Header Fields

Table 8.10.4-1 shows the Request Header Field usage for opening a WebSocket connection over http/https.

Table 8.10.4-1. Request Header Fields

Name

Value

Usage

Content-Type

media-type

M

Upgrade

"WebSocket"

M

Connection

"Upgrade"

M

Origin

url

M

Sec-WebSocket-Key

accept-key

M

Sec-WebSocket-Protocol

protocols

O

Sec-WebSocket-Version

version

M


For details of the request header field values and other methods of opening a WebSocket connection see [RFC6455].

8.10.4.1.4 Request Payload

The request has no payload.

DICOM PS3.18 2019c - Web Services