Book Image

OpenFlow Cookbook

Book Image

OpenFlow Cookbook

Overview of this book

Table of Contents (17 chapters)
16
Index

Sending and processing a hello message

The OFPT_HELLO message is used by both the switch and the controller to identify and negotiate the OpenFlow version supported by both the devices. Hello messages should be sent from the switch once the TCP/TLS connection is established and are considered part of the communication channel establishment procedure.

Tip

The switch should send a hello message to the controller immediately after establishing the TCP/TLS connection with the controller.

Getting started

To send a hello message, the switch should have established the TCP/TLS connection defined in the Connection setup on TCP and TLS recipe in Chapter 1, OpenFlow Channel Connection Establishment (Part 1).

How to do it...

As hello messages are transmitted by both the switch and the controller, the switch should be able to send, receive, and process the hello message. The following section explains these procedures in detail.

Sending the OFPT_HELLO message

The message format to be used to send the hello...