O-MI vs O-DF | difference between O-MI and O-DF in IoT
This page compares O-MI and O-DF used in IoT(Internet of Things) and mentions difference between O-MI and O-DF functions and formats. O-MI stands for Open Messaging Interface and O-DF stands for Open Data Format used in IoT interoperability.
Following are the features of O-MI and O-DF:
• These formats are published by Open Group.
• O-MI and O-DF are used similar to HTTP and HTML used in the web respectively.
• They can be used independent of each other.
• O-MI as the name suggests used for communication between IoT devices.
• O-DF as the name suggests used as data or payload format for
communication between IoT devices.
• They are specified using XML schema.
• They can be transported by
any underlying protocol such as HTTP,HTTPS, FTP, SMTP, XMPP etc.
• They help in publishing and discovering available information and services
• Read and Write of immediate information, historical information, alerts and events
can be done using these.
• It is possible to subscribe to information using Observer Design Pattern.
O-MI | Open Messaging Interface | IoT

O-MI supports operations such as read, write, subscribe and cancel as mentioned below.
• Read: Current & historical information, events, alerts etc...
• Write: Information e.g. sensor values, alerts, events, set points etc...
• Subscribe: to information e.g. adhoc, time limited such as event based vs regular interval, piggy backing,
with or without callback etc...
• Cancel: subscriptions before they actually expire
O-DF | Open Data Format | IoT
• O-DF is a generic format which represents "anything" in the IoT domain
• Same structure is used to publish, discover, query and retrieve information
• Can be extensible same as class inheritance concept used in OOP (Object Oriented Programming)
• Taxonomy may be provided by open group standards such as UDEF
REFERENCE
www.opengroup.org/
IoT Wireless Technologies
➤WLAN ➤THREAD ➤EnOcean ➤LoRa ➤SIGFOX ➤WHDI ➤Zigbee ➤6LoWPAN ➤Zigbee RF4CE ➤Z-Wave ➤NFC ➤RFID ➤Lonworks ➤CEBus ➤UPB