1. Supporting long polling Group Name: ARC WG Source: SeungMyeong, LG Electronics, seungmyeong.jeong@lge.com Meeting Date: 2013-0x-xx Agenda Item: TBD

2. Needs Entities in subscription/notification – Resource subscriber who created – Subscription hosting CSE who sends notifications Long polling is needed – In some cases, a notification cannot be sent to receiver due to NAT or firewall – Short polling by the subscriber is costly – The subscriber performs long polling to retrieve notifications from the hosting CSE © 2013 oneM2M Partners 2

3. ARC-2013-0473 at TP#7 (1/2) notification channel resource type for long- polling (notification retrieval), – has a virtual child resource © 2013 oneM2M Partners 3 Subscription Hosting CSE Resource Subscriber channel channel status retrieve notifications with long polling targeting “/ /channel” send triggered notifications to“/ /channel”

4. ARC-2013-0473 at TP#7 (2/2) Main feedback was why not use – short polling on is available, but costly – as it is cannot support long polling © 2013 oneM2M Partners 4 Subscription Hosting CSE Resource Subscriber latest … … retrieve notifications with long polling… targeting “???” container latest instance triggered notifications to be stored as instances

5. Summary What we need to do is – supporting long-polling notification retrieval to solve non-server capable resource subscriber issue – NOT re-using Resource subscriber does not matter whether notifications are stored in container of subscription hosting CSE or not. The subscriber only matters how to retrieve notifications. The hosting CSE might matter but that’s implementation issue. © 2013 oneM2M Partners 5

6. Suggestion Basically the same as suggestion of TP#7, – has a virtual child resource named “notification” utilize virtual resource concept/benefit – status is not needed – does not matter notification storage e.g., or 3 rd party external storage © 2013 oneM2M Partners 6 notification retrieve notifications with long polling targeting “/ /notification” triggered notifications conceptually channel INPUT conceptually channel OUTPUT

7. Example (1/2) © 2013 oneM2M Partners 7 ADN-AEMN-CSE 1. create request resource type: 2. create response new resource “MN-CSE/noti_ch” created 3. create request resource type: notificationURI: “MN-CSE/noti_ch/notification” 4. create response new resource “MN-CSE/sub” created

8. Example (2/2) © 2013 oneM2M Partners 8 ADN-AEMN-CSE 6. retrieve response content: notification data a notification is triggered send a notification to “/noti_ch/notification” (internally) 5. retrieve request target: “MN-CSE/noti_ch/notification” (  long polling URI) pending the retrieve request until a notification is received at notification channel

9. The other long polling Non-server capable entity does this for – Notification retrieval – Other CRUD requests retrieval channel hosting CSE re-targets request(s) to a channel Non server capable entity retrieves the request(s) from the channel © 2013 oneM2M Partners 9 CSE2base CSE1 retrieve request(s) with long polling from “entity2_base/entity1/channel” A request to CSE1 channel CSE1 AE2 Re-target Cannot send a request to a non server capable entity

10. Way Forward To bring a contribution proposing a new resource type – 2 main usages for non server capable AE/CSE Notification retrieval channel for AE/CSE  Notification channel (in ETSI TC M2M) CRUD request retrieval channel for CSE  Communication channel (in ETSI TC M2M) – Eventually both are for long polling – So it has more generic name