IETF draft-jeyatharan-mext-flow-tftemp- reference-01 Mohana Jeyatharan mohana.jeyatharan@sg. panasonic.com Chan-Wah Ng [email protected] 1 IETF
Feb 24, 2016
IETF
draft-jeyatharan-mext-flow-tftemp-reference-01
Mohana Jeyatharanmohana.jeyatharan@sg. panasonic.comChan-Wah [email protected]
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IETF
AgendaBackground on Flow Filtering via BearersFlow Binding Operation in 3GPP SAEMotivation for using TFT as traffic selectorObjective of this workOverview of Flow Binding Operation with TFT Impact of TFT state change on Flow Binding
RulesTFT Reference Traffic Selector Sub OptionWay Forward
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IETF
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
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P-GW
S-GW
Bearer ID 1(B1)[packet filter 1, packet filter 2]->TFTBearer ID 2(B2)[packet filter 3, packet filter 4]->TFT
Flow Filtering to
Bearer Performed
B1(Prefix1)
B1
B1
B2(Prefix1)
B2
B2
eNB
MN
Bearer filter Table1
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2
3
3
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
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P-GW
S-GW
B1
B1
B1
B2
B2
B2
e-PDG
eNB
MN
HoA, BID1, CoA(HoA), FID1, Packet filter 3HoA, BID1, CoA(HoA), FID2, Packet filter 4HoA, BID2, CoA(WiFi CoA), ->Default Access
Bearer ID 1(B1),[packet filter 1, packet filter 2]->TFTBearer ID 2(B2),[packet filter 3, packet filter 4]->TFT
3G(Home Link)/HoAWiFi/CoA
IPv6 filtering
Bearer filtering
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1
Flow binding BU : BID1, FID1, FID2,
BID2 2 23
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Flows tied to packet filters 3
and 4 are attached with
B2
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
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
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.
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IPv6 HeaderBU Mobility Header
Mobility OptionsBID2 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]->TFTBearer ID 2(B2),[packet filter 3, packet filter 4]->TFT
3G WiFiMN
Flow binding BU w TFT
Ref
P-GW flow binding table with TFT Ref
Flow Binding BU with TFT Ref
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2
1
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
TFT Reference Traffic Selector Sub Option
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Sub-opt TypeSub-opt LenTS format Reserved
TFT Ref
Sub-opt Type: assigned to 3 as in MEXT Flow Binding DraftSub-opt Len: Total length is 3 octets for this sub-optionTS Format: Needs to be assigned by IANA to highlight TFT refTraffic Selector formatReserved: Set to 0TFT Ref: 8 bit field to carry the Bearer ID
Way ForwardAre 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?
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