1. IETF draft-jeyatharan-mext-flow-tftemp-reference-01 Mohana Jeyatharan mohana.jeyatharan@sg. panasonic.com Chan-Wah Ng chanwah.ng@sg.panasonic.com 1 IETF

2. Agenda Background on Flow Filtering via Bearers Flow Binding Operation in 3GPP SAE Motivation for using TFT as traffic selector Objective of this work Overview of Flow Binding Operation with TFT Impact of TFT state change on Flow Binding Rules TFT Reference Traffic Selector Sub Option Way Forward 2 IETF

3. Background on Flow Filtering via Bearers Flow filtering via 3GPP Bearers: ◦ For improved QoS, one or more dedicated bearer(s) creation initiated by P-GW ◦ B1->default bearer ◦ B2 ->dedicated bearer ◦ Each dedicated bearer (and in some cases default bearer) assigned a TFT ◦ B1-> packet filter 1, packet filter 2 ◦ B2-> packet filter 3, packet filter 4 ◦ Data flow that can be matched to a packet filter of TFT is attached with appropriate Bearer ID ◦ Data packet matching Packet filter 3 has B2 attached to it ◦ Bearer ID embedded in data packet helps the gateways to identify the needed QoS treatment that has to be performed 3 P-GW S-GW Bearer ID 1(B1)[packet filter 1, packet filter 2]->TFT Bearer ID 2(B2)[packet filter 3, packet filter 4]->TFT Flow Filtering to Bearer Performed B1(Prefix1) B1 B2(Prefix1) B2 eNB MN Bearer filter Table 1 2 1 2 3 3

4. Default access Flow Binding in 3GPP SAE for Simultaneous Access  P-GW supports flow filtering to interface and flow filtering to bearers  Two tier filtering.  Tier one: filtering for interface  Tier two: filtering for bearer  If WiFi access is default access and MN wants packet filters 3 and 4 to enjoy higher QoS, MN will send flow binding BU to ensure flows tied to packet filter 3 and packet filter 4 receive QoS treatment  P-GW filters only data flows tied to Packet filter 3 and packet filter 4 via 3G  During 3G filtering, flows tied to packet filter 3 and packet filter 4 will be filtered to bearer B2 4 P-GW S-GW B1 B2 e-PDG eNB MN HoA, BID1, CoA(HoA), FID1, Packet filter 3 HoA, BID1, CoA(HoA), FID2, Packet filter 4 HoA, BID2, CoA(WiFi CoA), ->Default Access Bearer ID 1(B1),[packet filter 1, packet filter 2]->TFT Bearer ID 2(B2),[packet filter 3, packet filter 4]->TFT 3G(Home Link)/HoA WiFi/CoA IPv6 filtering Bearer filtering 1 1 Flow binding BU : BID1, FID1, FID2, BID2 2 2 3 3 Flows tied to packet filters 3 and 4 are attached with B2

5. Motivation for using TFT as Traffic Selector  All packets filtered to 3G interface at the IPv6 layer will need to match Packet filters of TFT. Otherwise packet loss can occur.  Sending Reference to TFT in flow binding solves this issue  P-GW has packet filters with appropriate descriptions stored. Thus, flow binding BU need not have explicit flow descriptors in the traffic selector sub-option.  Using TFT as traffic descriptor reduces flow binding BU packet size  If new packet filters are added to a TFT by P-GW, only a refresh flow binding BU with a single FID is sufficient rather than sending a new flow binding BU with multiple FIDs for the new packet filters created.  Reduces flow binding signalling and saves battery power of MN  If packet filters are removed from the TFT by the P-GW, again only a refresh flow binding BU with a single FID is necessary rather than performing removal of multiple individual packet filters (ie. multiple FIDs in the flow summary mobility option. )  Reduces flow binding signalling and saves battery power of MN

6. Objective Objective of this Work  To propose a new Traffic Selector format to be used for the Traffic Selector Sub-option proposed in the MEXT flow binding draft  Introduce a new traffic selector sub option format in parallel to the currently available binary traffic selector format, to address flow binding in a 3GPP specific scenario  Introduce a new format value for the TS field of the traffic selector sub option and use a new data field value for the traffic selector field

7. Overview of Flow Binding Operation with TFT  Creating Flow Binding Rules  TFT Reference as a new traffic selector format  BU formed with TFT Reference Traffic selector sub-option attached to FID option  Bulk flow binding BU sent and entries created  Refreshing Flow Binding Rules ◦ Same as in MEXT Flow binding draft.  Deleting Flow Binding Rules ◦ Same Operation as in MEXT Flow binding draft. 7 IPv6 Header BU Mobility Header Mobility Options BID2 option (care of binding for WiFi) BID1 option (care of binding for 3G) FID1 Option [TFT reference traffic selector sub-option ->Bearer ID2] P-GW S-GW e-PDG HoA, BID1, CoA(HoA), FID1, Bearer ID2(packet filters 3 and 4) HoA, BID2, CoA(WiFi), ->Default Access Bearer ID 1(B1),[packet filter 1, packet filter 2]->TFT Bearer ID 2(B2),[packet filter 3, packet filter 4]->TFT 3G WiFi MN Flow binding BU w TFT Ref P-GW flow binding table with TFT Ref Flow Binding BU with TFT Ref 1 2 2 2 1

8. Impact of TFT State Change on Flow Binding Rules with TFT Reference  Creation of TFT by P-GW ◦ MN will send Flow binding BU with TFT ref in traffic selector sub- option if MN wants packet filters tied to new TFT to be sent via 3G and receive appropriate QoS  Changing TFT by P-GW ◦ If new packet filter added to TFT, MN may perform Refresh Flow binding BU as in MEXT flow binding draft to get adequate QOS for new packet filter ◦ If packet filter is removed from a TFT, MN may perform Refresh Flow binding BU as in MEXT flow binding draft and decide to send the flows tied to deleted packet descriptors via the default path (WiFi)  Removal of TFT by P-GW ◦ MN needs to send flow binding deletion BU as in MEXT flow binding draft if MN decides the flows tied to deleted TFT need not traverse via the 3G interface

9. TFT Reference Traffic Selector Sub Option 9 Sub-opt TypeSub-opt LenTS formatReserved TFT Ref Sub-opt Type: assigned to 3 as in MEXT Flow Binding Draft Sub-opt Len: Total length is 3 octets for this sub-option TS Format: Needs to be assigned by IANA to highlight TFT ref Traffic Selector format Reserved: Set to 0 TFT Ref: 8 bit field to carry the Bearer ID

10. Way Forward Are people convinced that the TFT Reference TS format is useful to be applied in 3GPP scenario? Do people think that this TFT Reference format is a needed work and IETF should do it? Any possibility of adopting it as a WG item? 10