Book Image

OpenFlow Cookbook

Book Image

OpenFlow Cookbook

Overview of this book

Table of Contents (17 chapters)
16
Index

Sending and processing an echo request and a reply message

Echo request and reply messages are used by both the controller and the switch to maintain and verify the liveliness of the controller-switch connection. Echo messages are also used to calculate the latency and bandwidth of the controller-switch connection.

Tip

On reception of the echo request message, the controller should respond an with echo reply message.

Getting started

To send echo request and reply messages, the TCP/TLS connection establishment procedure defined in the Connection setup on TCP and TLS recipe of Chapter 1, OpenFlow Channel Connection Establishment (Part 1) should be used.

How to do it...

As echo messages are transmitted by both the switch and the controller, the controller should be able to send, receive, and process these messages. The following sections explain these procedures in detail.

Sending the OFPT_ECHO_REQUEST message

The OpenFlow specification doesn't mention how frequently this echo message is to be...