1
IP/MPLS QoS over ATM
3Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Agenda
• IP COS over ATMIP COS over ATM
• IP COS over MPLS
• MPLS CoS over ATM
• IP QoS for Tag VPNs
• Conclusion
4Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
IP COS over ATM: Overlay Model
IP Layer: Diff-Serv IP Layer: Diff-Serv MechanismsMechanisms• Connectionless Per packet
precedence (DS-byte) indicating “priority” for each packet
• limited number of COSs
ATM Backbone: ATM Backbone:
ATMF/ITU-T Qos mechanismsATMF/ITU-T Qos mechanisms• Per Connection Qos
• Very strict Qos
• Traffic classes:CBR, VBR, VBR-RT, UBR, ABR
• Traffic Parameters:PCR, MCR, SCR,..
How do I mapHow do I mapthe two worlds ???the two worlds ???
How do I mapHow do I mapthe two worlds ???the two worlds ???
5Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
IOS “IP ATM COS”: Principles
• The ATM service The ATM service contracted must be contracted must be provided! (at least, loss provided! (at least, loss less!)less!)
• Router’s traffic Router’s traffic must be compliant must be compliant with respect to with respect to ATM service ATM service contractedcontracted
6Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
IOS “IP ATM COS”: Principles
• Congestion pushed back at the edgeCongestion pushed back at the edge
• per-VC IP Queue developsper-VC IP Queue develops
• IP-intelligent QoS Mechanisms in the IP-intelligent QoS Mechanisms in the routerrouter
• Because: ATM switch does not Because: ATM switch does not understand IPunderstand IP
7Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
IP ATM COS-Ph1: Per-VC WRED
• Single VC per Pair of Routing Peers • Multiple Service Classes on same VC• WRED runs on each VC queue
VC1
VC2
8Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Distributed VIP2 Architecture
Route Switch Processors
VIP2 VIP2 VIP2xIPxIP
i
SwitchProcessor
PortAdapter
PortAdapter
PortAdapter
PortAdapter
PacketMemory
PPCCII
PPCCII
CCyyBBuuss
Cisco 7500
• Distributed Switching• Distributed Services• Distributed WRED/WFQ
9Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
ATM PA-A3 Architecture
SARSAR
PC
I
High-performance SAR
Per-VC Queues/ Traffic Shaping
ATM Shaping: CBR, VBR, ABR (all 3
modes) and UBR
Single-wide port adapter for Cisco
7200/7500
DS3 E3
OC3c/STM1 MM OC3c/STM1 SM-IR OC3c/STM1 SM-LR
10Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Per-VC WRED : Intelligent IP Packet Discard
VIP2-50 PA-A3-XX
Per-VCPer-VCWRED:WRED:
Intelligent DiscardIntelligent Discard
Threshold Exceeded
VC1
VC2
VC3
No discardNo discardon PAon PA
Traffic Traffic ShapingShaping
Per-VCPer-VCQueuesQueues
11Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Per-VC WRED (cont.)
• ATM router interface “shapes” according to VBR, CBR or ABR* requirements
• Very low loss on ATM network is essential–Easy with CBR, VBR
–Good match to ABR allowing elastic use of all available bandwidth (assuming low loss implementation, e.g. BPX)
–Not effective with UBR VCs
• VCs not backlogged are unaffected!
• VC dimensioned so that all COSs get their appropriate quality
* ABR : Future
12Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Per-VC WRED CLI
WRED profile:random-detect group <group-name>
exponential weighting constant <1.16>
precedence <0..7, rsvp> <min-th> <max-th> <mark-p>
To activate a WRED profile on a PVC:atm pvc <vcd> <vpi> <vci> <aal-encap> [[<mid_low> <mid_high>]
[<peak> <average> <burst>]] [oam <seconds>] [inarp [<minutes>] [random-detect [<group_name>]
13Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Per-VC WRED CLI
WRED parameters bound to a VC:
show queueing red int <atm_subinterface> [vc [[<vpi>/]<vci>]]
Queuing statistics of an ATM PVC:
show queueing int <atm_subintf> [vc [[<vpi>/]<vci>]]
14Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
IPATMCOS-Ph1 CLI
• Cf “IPATMCoS-Ph1” Design Guide
15Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Per-VC WRED CLInf-7505-1# show runinterface ATM1/1/0.47 point-to-point atm pvc 47 0 47 aal5snap 10 10 1 random-detect wredgroup1
nf-7505-1#show queueing redVC 0/47 -random-detect group default:exponential weight 9precedence min-threshold max-threshold mark-probablity---------------------------------------------------------------0: 20 40 1/101: 22 40 1/102: 24 40 1/103: 26 40 1/10
16Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Per-VC WRED CLI
7513-1-31#sh queueing int atm 11/0/0.103 VC 5/103
ATM11/0/0.103 queue size 83 packets output 1345843, drops 1590472 WRED: queue average 82 weight 1/512, max available buffers 1021 Precedence 0: 40 min threshold, 81 max threshold, 1/10 mark weight 1344366 packets output, drops: 134304 random, 1456168 threshold Precedence 1: 45 min threshold, 81 max threshold, 1/10 mark weight (no traffic) Precedence 2: 50 min threshold, 81 max threshold, 1/10 mark weight (no traffic) Precedence 3: 55 min threshold, 81 max threshold, 1/10 mark weight (no traffic)
IP ATM COS-Ph2: Bundle
• A single Bundle routing neighborship!
• Flexible IP CoS mapping to VCs
• RED (WRED) runs on each VC [email protected]’98 17© 1998, Cisco Systems, Inc.
VC2: ABR
VC1: VBR-nrtPrec: 5 - 7
Prec: 0 - 4
1! IGP neighborship
18Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Precedence to VC Mapping
• Mapping of precedence to VCs – 1 Precedence to 1 VC
– Several Precedences to 1 VC
Prec: 5 - 7
Prec: 0 - 4 VC2: ABR
VC1: VBR-nrt
19Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
VC Provisioning
• VCs are dimensioned based on expected load for the precedence(s) level transported on that VC
• More isolation between classes
• At the expense of – less statistical multiplexing,
– more complex provisioning/engineering
VC2: ABR ??? PCR, MCR
VC1: VBR-nrt ??? SCR, PCR, MBS
20Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
VC Bundle Mgnt
• Two Modes:
– Protected VC rule : when a protected VC goes down, the bundle goes down
– Protected group rule : when all members in the protected group fail, the bundle is delared DOWN
–When a bundle is declared down, no traffic is forwarded out of the bundle (EVEN some VCs are still up).
21Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Bumping
• VC bumping: possibility for a traffic mapped to a VC X to be forwarded onto another VC Y, in case of failure of X.
–Implicit bumping rule : Y is the next lower precedence level VC is selected,
–Explicit bumping rule : Y is explicitely specified.
22Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Bumping (Cont.)
• Traffic is restored to the original VC when it comes back.
• « Reject Bumping »: It is possible for a VC to be configured not to accept the bumped traffic
• When no alternate VC for some bumped traffic, the bundle will be declared down.
23Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Bumping (Cont.)
• To prevent from declaring a bundle DOWN due to the failure of the lowest precedence VC, explicit bumping should be configured on the lowest precedence.
• Should be used in conjunction with the protected group rule
• If the VC which carries the bumped traffic fails also, the traffic will follow the bumping rules specified for that VC.
24Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Bundle example
TOS 6-7 <-> VC 1 - ATM VBR-nrtProtected VC
TOS 4-5 <-> VC 2 - ATM VBR-nrtProtected Group- bump explicit 7
TOS 0-1 <-> VC 4 - ATM UBR Protected Group
TOS 2-3 <-> VC 3 - ATM VBR-nrtProtected Group - bump implicit
25Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
VC1 Failure
Protected VC
26Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
VC2 Failure
Explicit bumping
27Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
VC3 Failure
Implicit bumping
28Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
VC2 & 3 & 4 Failures
Protected group
29Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
CLI details
• Cf “atmvcbundle.doc” or Manuals
30Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
IP ATM COS Roadmap
• Phase 1 - Per-VC WRED (single VC)–Cisco 7500 (VIP2-50/PA-A3)
–FCS since 11.1(22)CC
• Phase 2 - Precedence Mapping (multiple VC)– Cisco 7200 (NPE-200/PA-A3)
– Bundle Management
– 12.0(3)T FCS 1Q99 (planned)*
• Phase 3 - Per-VC WFQ– Per-VC WFQ
31Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
IP ATM COS Summary • IP gateway uses/conforms to ATM
service contract (ATM QoS)
• Queues are developed in router where intelligent decisions can be made (IP QoS)
• Does not requires any proprietary features onto ATM switches
Still OVERLAY!
32Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Agenda
• IP COS over ATM
• IP COS over MPLSIP COS over MPLS
• MPLS CoS over ATM
• IP QoS for Tag VPNs
• Conclusion
33Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Agenda
• IP COS over ATMIP COS over ATM
• IP COS over MPLS
• MPLS CoS over ATM
• IP QoS for Tag VPNs
34Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
What is Tag/MPLS COS ?
ConventionalRouter
Tag EdgeRouters
ATM-TSR
Frame-TSR
Tag
Non-Tag
Non-Tag
IP Diff-Serv COSend-to-end
Support of Consistent IP Diff-Serv Classes Support of Consistent IP Diff-Serv Classes of Service end-to-end when part of theof Service end-to-end when part of the
network is running MPLSnetwork is running MPLS
35Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
MPLS CoS: 3 steps
• Step1: NON-MPLS
– CAR/QPPB/CiscoAssure
– WFQ/WRED
MPLSIPv4 IPv4STEP1
STEP2
STEP3
36Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
MPLS CoS: 3 steps
• Step2: Label Imposition
– LER sets MPLS CoS bits = IPv4 Prec; or
– CoS is associated with label via LDP
IPv4 Packet MPLS Hdr
Prec: xyz Prec: xyzMPLS CoS: xyz
Non-MPLS Domain
MPLS Domain
0 1 2 30 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| Label | CoS |S| TTL |
37Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
MPLS CoS: 3 steps
• Step2: Label Imposition
– LER sets MPLS CoS bits = IPv4 Prec; or
– CoS is associated with label via LDP
IPv4 Packet
Prec: xyz
P/p CoS1 17
P/p CoS2 22
P/p CoS3 25
P/p CoS4 12
Dest-CoS Label
0 1 2 30 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| Label | UUU |S| TTL |
38Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
MPLS CoS: 3 steps
• Step 3: DiffServ inside MPLS domain based on MPLS-CoS field or CoS associated with Label
– 3a: Frame MPLS CoS
– 3b: ATM MPLS CoS
39Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Frame MPLS CoS
• Straightforward!!!
• Same Mechanisms as IP CoS
• Class Marker
– MPLS CoS instead of Precedence; or
– MPLS Label instead of Precedence
• Undistinguishable from IPv4 DiffServ
40Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
ATM MPLS CoS
• Great Opportunity!
• Peer Model instead of Overlay
– IP intelligence at every hop
– IP-friendly mech. on ATM switches!
• Diffserv instead of per-VC ATM QoS
– Superior Resource Utilisation
– Simpler Resource Allocation
41Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Peer vs Overlay
Overlay Model:IP Intelligence
Around
Peer Model:IP Intelligence
at every hop
42Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Agenda
• IP COS over ATM
• IP COS over MPLS
• MPLS CoS over ATMMPLS CoS over ATM
• IP QoS for Tag VPNs
• Conclusion
43Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Challenges
• No CoS field in ATM cells
• No WRED in switches
– WFQ is often available in atm switches under the form of a WRR implementation
44Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Two Modes
• Single LSP in ABR mode
• Multi-LSP in TBR mode
– Each has advantage and drawbacks
TBR: Tag Bit Rate: ATM service category designed for Differv/MPLSTBR: Tag Bit Rate: ATM service category designed for Differv/MPLS
45Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Single `VC’ ABR mode
• Extention of “IPATMCoS” feature
• ABR control algorithms are enabled on LSPs
• ATM-LSRs push congestion towards edge LSRs
• Edge-LSRs: WRED/WFQ per-LSP queues
ABR TSP
ATM TSR
46Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Single VC ABR mode
• ATM-LSR Scheduling = per-VC ABR
• ABR parameters:
– MCR is effectively zero (to avoid loss/blocking)
– “Relative bandwidthRelative bandwidth” parameter carried by TDP and used by ABR algorithm
47Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Single VC ABR: Example
A
B
London Paris
KleinStadt
Tarifa
• Equal sharing of link A-B is not always desirable:– Configure relative bandwidth on router-pair basis,
e.g. Tarifa-KleinStadt = 1; London-Paris = 100
• Resource Allocation :– Sharing of Bandwidth across Edge Pairs via “Relative BW” on a per
TSP basis
– Sharing of Bandwidth across COS performed through WRED on Edge
Per VCABR
48Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Multi-VC TBR mode
• Up to 4 parallel TSPs for the same prefix
• CoS <--> TSPs mapping
• Optional setting of CLP for some CoS
Parallel TBR TSPs
ATM TSR
Control Plane
49Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Multi-VC TBR mode
• Edge ATM-LSR: per CoS WFQ + per CoS WRED
• ATM-LSR: per CoS WFQ + per CoS WEPD
Parallel TBR TSPs
ATM TSR
CoS Mechanism in cell Data path
50Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Multi-VC TBR mode: Example
• Queuing on all links is per-class WFQ (not per TSP)
• Resource allocation – Assign weight to each class on per-link basis
(e.g. Premium gets 80% of link, Standard gets 20%)– Choice of weights based on expected load & desired
performance PER CLASS– No per-router-pair configuration (config independent of
topology & geography)
Per COSWFQ
51Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Multi-VC TBR Mode: Example
• EPD is not RED, but...
• EPD thresholds can be set to different levels for different classes ---> WEPD
• Threshold scaling ensures that buffers are not wasted
–allocation to each class decreases as total free buffer space decreases
52Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Single-ABR vs Multi-TBR
• Multi-VC TBR Mode:– Congestion managed directly at every hop (IP and ATM hops)
– Possible Discard at every hop
– Resource Allocation per COS per link; does not have to concern itself with topology and geography
• Single-VC ABR:– No Loss in the ATM fabric
– Discard possible only on the Edge performed by Routers
– Resource Allocation optionally per Pair of Edge Routers. Sharing of bandwidth across COS indirect via WRED profiles
53Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
ATM MPLS CoS: other cases
• MPLS CoS over ATM-Forum PVC’s
• MPLS CoS over MPLS VP
54Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Tag over ATMF/ITU-T ATM PVC
• Generic Frame MPLS CoS Case!– A Frame TSR use “normal” ATM PVC with chosen ATM QoS– Perform all Service Differentiation on Frame TSRs at edge of ATM
ATMATM PVCPVC
Tag ATMTag ATM
TDPTDP
ATM Forum ATMATM Forum ATM
TDPTDPTDPTDP
TDPTDP
TSPs
55Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Tag COS over Tag VP Tunnels
• ATM-LSR runs MPLS CoS inside an ATM VPs
• ATM VP is a virtual trunk between L1 and L2
TDPTDP
ATM Forum ATMATM Forum ATM
TDPTDP
ATM VP
Tag Switching
TDPTDP
L1L1 L2L2
56Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Agenda
• IP COS over ATM
• IP COS over MPLS
• MPLS CoS over ATM
• IP QoS for Tag VPNsIP QoS for Tag VPNs
• Conclusion
57Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Tag VPN QoS
• 2 very distinct point of views:
– How the SP will market the service (SLA)
– What are the mechanisms for SP to meet the commitments/SLA
• FR analogy:
– sell 64 kb/s CIR for 99.5% of the time
– reserve 64/overbooking kb/s + admission control + selective discard + …
58Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
How to market MPLS VPN CoS?
VPN SP
ECR 128kVPN_A
site 2 ICR 256k
VPN_A site 3
ECR 128k
ICR 256k
ICR 256k
ECR 128k
VPN_A site 4
59Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Proposed SLA for CoS C1
• As long as for each site S of VPN X:
– S sends less than ICR
– S receives less than ECR
• Then:
– loss property is 10^(-n1)
– RTT is < m1 ms
60Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Should offer different CoS!
CoS X: [nx, mx], price Px
Gold: [-10, 100ms], $$$
Silver: [-8, 200ms], $$
BE: [be, be], $
61Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
• Should not be marketed as Frame Relay QoS:
– N1 kb/s guaranteed from Site 1 to Site 2
– N2 kb/s guaranteed from Site 1 to Site 3
– N3 kb/s guaranteed from Site 2 to Site 3
– …
• Layer 2 based VPNs (ie FR or ATM) address that need
How it should not be marketed
62Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
How to meet SLA
• Enforcement of ICR:– CAR: policing in/out of profile
• MPLS CoS in the SP’s backbone– single-ABR, multi-TBR mode
– DiffServ engineering
– Per-Class LSP Traffic Engineering in the backbone
• Enforcement of ECR
63Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
DiffServ Engineering
• Scalability: no per-VPN QoS in BB
• Per-Class Scheduling/Discarding at every hop
• Resource Allocation based on ICR/ECR sold– share each trunk between different Classes – start conservative– then monitor traffic per class and fine tune– Optimise with per-class Traffic Engineering– Cisco Service Management tool for Tag VPN QoS provisioning
64Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Per-VPN WFQ
• For ATM-ABR model or ATMF PVC
• Scalability: only at edge!
VPN_1VPN_1 Per VC Q on Tag ABR-VC to Remote PE Per VC Q on Tag ABR-VC to Remote PE
Per VPN WFQ
Per COSWRED
PEPEATM Tag BackboneSingle-VC ABR Mode
VPN_2VPN_2
VPN_3VPN_3
65Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
MPLS VPN CoS: Sum up
• Frame, single LSP
• ATM, single-ABR mode
• ATM, multi-TBR mode
• ATM, ATM-Forum/ITU pvc
66Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Frame, single LSP
VPN_A VPN_A
VPN_A
VPN_BVPN_B
10.2
10.1
11.5
11.6PE
PE
P P
PPPE 3
PE 4
CE
CE
CE
CE
-2 PE: Single TSPper COS Scheduling& Discard
-4- non Tag COSon output:WRED, TS
-3-P: Single TSPper COS
Scheduling/Discard
COS_0
COS_1
COS_7
Per COS WFQ
Per COSWRED
-1-CAR:Mark in-profile (eg
Silver VPN)Mark out-profile
(Optionally Mark per application, per user…)
Per COS WFQ
Per COSWRED
67Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
ATM, single-ABR mode
VPN_A VPN_A
VPN_A
VPN_BVPN_B10.210.2
10.1
11.5
11.6
PE
PE
P P
PPPE 3
PE 4
CE
CE
CE
CE
-1-CAR:Mark in-profile (eg
Silver VPN)Mark out-profile
(Optionally Mark per application, per user…)
-2- PE Scheduling& Discard
-4- non Tag COSon output:WRED, TS
VPN_1
VPN_2
VPN_N
Per VC Q(to PE 3)
Per VPN WFQ
Per COSWRED
VPN_1
VPN_2
VPN_N
Per VC Q(to PE 4)
Per VPN WFQ
Per COSWRED
-3- ABR TSP
Per VC Queuing,“Relative Relative BandwidthBandwidth” usedto apportion bandwidthacross competing ABR VCs
68Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
ATM, multi-TBR
VPN_A VPN_A
VPN_A
VPN_BVPN_B10.210.2
10.1
11.5
11.6PE
PE
P P
PP PE 3
PE 4
CE
CE
CE
CE
-2 PE Scheduling& Discard
-4- non Tag COSon output:WRED, TS
-3- TBR Multi-VC
Per Class WFQ
COS_0
COS_1
COS_7
Per COS WFQ
Per COSWRED
-1-CAR:Mark in-profile (eg
Silver VPN)Mark out-profile
(Optionally Mark per application, per user…)
Per COSDynamicWEPD
69Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
ATM, ATM-forum/ITU PVC
VPN_A VPN_A
VPN_A
VPN_BVPN_B10.210.2
10.1
11.5
11.6PE
PE PE 3
PE 4
CE
CE
CE
CE
-1-CAR:Mark in-profile (eg
Silver VPN)Mark out-profile
(Optionally Mark per application, per user…)
-2- PE Scheduling& Discard
-4- non Tag COSon output:WRED, TS
VPN_1
VPN_2
VPN_N
Per VC Q(to PE 3)
Per VPN WFQ
Per COSWRED
VPN_1
VPN_2
VPN_N
Per VC Q(to PE 4)
Per VPN WFQ
Per COSWRED
-3- ATM Forum/ITU-T ATM PVC (CBR, VBR,
ABR)
“Normal”ATM Forum/ITU-T scheduling/discarding (CBR, VBR, ABR)
Non-Tag CapableATM Switches
70Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
Agenda
• IP COS over ATM
• IP COS over MPLS
• MPLS CoS over ATM
• IP QoS for Tag VPNs
• ConclusionConclusion
71Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
IP COS over ATM: Conclusions
• IP is the end2end QoS enabler
–Applications are running on IP, and Networks are constituted of diverse media's. Therefore QoS end-to-end has to be provided by IP
• DiffServ model for IP CoS
–IETF’s Differentiated Services is an extremely scalablescalable COS model and is likely to become widespread
72Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
IP COS over ATM: Conclusions
• IP Diff-Serv’s CoS over ATM:
– Overlay: IOS “IP ATM COS “
– Peer: MPLS COS ATM-LSR’s: IP controlled and IP QoS aware
tighter IP/ATM integration
73Cisco Systems ConfidentialClarence Filsfils - atm-mpls-cos
IP COS over ATM: Conclusions
• Perfect illustration: MPLS VPN’s
– Scalability of Diff-Serv COS
– Several SLA’s (Gold, Silver, BE)
– integration IP & ATM