1. Routing Problem of the Current Architecture Group Name: ARC Source: Hongbeom Ahn, LG Electronics, hongbeom.ahn@lge.com Meeting Date: 2014-02-07 Agenda Item: Contribution

2. Service Layer Routing in ETSI TC M2M © 2014 oneM2M Partners ARC-2014-0148-Routing_Problem 2 DA GSCL GA Gateway Device NSCL NA M2M Server Network Application DSCL DA Device NSCL NA M2M Server Network Application A GSCL or DSCL is only connected with a NSCL over service layer domain Only 1 SCL-hop routing case is existed 1 1 1 1

3. Problem Statement (1/5) However, Based on our current architecture model oneM2M system have more than 1 CSE-hop routing cases – A message is forwarded over multiple Mcc reference points Due to the fact, our architecture might have some problems – A message is (1) forwarded over more than a Mcc reference point and a Node in the path has (2) multiple-outgoing paths CSE 1 AE CSE 3 CSE 4 CSE 5 IN MN ASN From CSE 1 to CSE 4 : 3 CSE-hops routing case 1 1 2 2 3 3 CSE 2 MN © 2014 oneM2M Partners ARC-2014-0148-Routing_Problem 3

4. CSE 6 CSE 5 CSE 3 IN MN CSE 4 MN MN-CSE 5 has multiple out- going paths toward 1)MN-CSE 3 2)MN-CSE 4 CSE 1 AE ASN 1 CSE 2 AE ASN 2 Case 1 (Proper Next Hop) – A message is sent from IN-CSE 6 to ASN-CSE 1 Problem Statement (2/5) In this case, MN-CSE 5 needs to determine the proper next hop for the successful message routing in this case, the proper next hop is MN-CSE 3. To determine this, MN-CSE 5 must have a sort of routing information, similar to IP routing table © 2014 oneM2M Partners ARC-2014-0148-Routing_Problem 4

5. CSE 1 AE CSE 2 CSE 3 ASN MN CSE 5 MN CSE 6 MN In this case, MN-CSE 2 needs to determine the proper next hop for routing in this case, the proper next hop is MN-CSE 3 for effective routing (if the cost of each hop is the same) MN-CSE 2 has multiple out- going paths toward 1)MN-CSE 3 2)MN-CSE 5 CSE 7 IN Problem Statement (3/5) Case 2 (Effective Routing) –A message is sent from ASN-CSE 1 to IN-CSE 7 © 2014 oneM2M Partners ARC-2014-0148-Routing_Problem 5

6. CSE 1 CSE 2 IN MN CSE 3 MN IN-CSE 1 has multiple out- going paths toward 1)MN-CSE 2 2)MN-CSE 3 CSE 4 AE ASN CSE 5 AE ASN Problem Statement (4/5) Case 3 (Proper Next Hop) –A message is sent from IN-CSE 1 to ASN-CSE 4 In this case, the IN-CSE 1 needs to determine the proper next hop for the successful routing in this case, the proper next hop is MN-CSE 2 and the IN-CSE 1 must have all the registration information of Node behind the MNs © 2014 oneM2M Partners ARC-2014-0148-Routing_Problem 6

7. Summary of the problem statement – In our current architecture – When a message is (1) forwarded over more than a Mcc reference point and an entry/intermediate Node in the path has (2) multiple- outgoing paths – The Node needs to determine the proper next hop (CSE) for successful and effective routing Difficult to support this case described above – Lack of time to fully develop – However, this current TS-0001 needs to be fixed to solve this problem – Better to simplify our current architecture for technical consistency Problem Statement (5/5) © 2014 oneM2M Partners ARC-2014-0148-Routing_Problem 7

8. Proposals (1/2) To simplified our solution No MN to MN connection in release 1 – Only ASN or ADN – MN – IN connection – Complex configurations for subsequent release – Relevant figures and normative texts shall be modified – Please see the relevant contribution © 2014 oneM2M Partners ARC-2014-0148-Routing_Problem 8

9. Proposals (2/2) Limitation on multi-hop routing case – The Local CSE shall ensure the selection of the proper next hop among the registered Intermediate CSEs. The selected next hop shall be registered with the Hosting CSE and shall forward the request to the Hosting CSE. – Please see the relevant contribution CSE 1 CSE 2 IN (Local CSE) MN (Intermediate CSE) CSE 3 MN CSE 4 AE ASN (Hosting CSE) CSE 5 AE ASN Proper Next Hop © 2014 oneM2M Partners ARC-2014-0148-Routing_Problem 9

10. CSE 2 CSE 3 IN (Intermediate CSE) MN (Intermediate CSE) CSE 4 MN CSE 5 AE ASN (Hosting CSE) CSE 6 AE ASN Proper Next Hop CSE 1 AE ASN (Local CSE) Plus, this configuration is also applied for the second proposal – The Intermediate CSE shall ensure the selection of the proper next hop among the registered Intermediate CSEs. The selected next hop shall be registered with the Hosting CSE and shall forward the request to the Hosting CSE. © 2014 oneM2M Partners ARC-2014-0148-Routing_Problem 10