4_22109-fgc101414_en_b_pdfv1r5

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

1/21

TELLABS 8600Quality of Service

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

2/21

Tellabs 8600 Technical Presentation, QoS | Commercial in confidence | 4/22109-FGC101414 Uen, Rev B | 2012-10-24 | Page 2

QoS Mapping Alternatives

Configurable mappings Node internal QoS (packet priority) may

come from MPLS label or IP packet LSR uses outer label LER QoS mapping depends on tunneling

model (pipe, short pipe, uniform) EF AF BE

IPInner (VPN)

LabelOuter Label

IP

Inner (VPN)

Label

Outer

Label

EXP EXP DSCP

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

3/21



8600 node internal QoS can be mappedfrom 802.1p (VLAN PRI) bits or IP DSCPif MPLS labels not present

Freely configurable Can be used e.g. in MPLS network

ingress EF AF BE

IPEthernet

IPEthernet

802.1p DSCP

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

4/21



VLAN mapped to QoS priority byconfiguration

Policers for individual VLANs or wholeport

VLAN shaping in BE traffic class ATM VP/VC mapped to service

category by configuration ATM circuit parameters (PCR, SCR,

CDVT) according to service category

Optional ATM VC shaping

EF AF BE

Ethernet

802.1q(VLAN)

CBR VBR UBR

ATM

VP/VC

UBR+

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

5/21


DiffServ QoS SelectionAlternatives

L2 or L3 packet header DSCP MPLS EXP L-LSP VLAN or PRI

L3/L4 ACL (see figure) ATM VP or VC mapping to

DiffServ QoS Ingress port specific QoS

mapping

Access Control List Options

L3 Source Address

L3 Destination Address

L3 ToS/DSCP

L3 Fragmented packet

L4 ProtocolL4 Source Port

L4 Destination Port

L4 Code bits

IP/MPLS

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

6/21


DiffServ Policer

CIR

Mbps

PIRPBS

CBSCBS

Time

PBS t PIR

PIR bucketPIR tokens

CBS t CIR

CIR bucket

CIR tokens

Packet

Packet

Packet

Packet

Arrivals Configurable action depends on

PHB (EF, AFxy, BE) CIR, CBS, PIR and PBS

2K policers trTCM/srTCM

Packet drop precedence Green/Yellow/Red Colour-blind and colour-aware

modes Rate policing granularity 500 ppm

(0,05%) Mininimum policed rate 15 kbps

Max. burst size 8 Mbytes

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

7/21Tellabs 8600 Technical Presentation, QoS | Commercial in confidence | 4/22109-FGC101414 Uen, Rev B | 2012-10-24 | Page 7

Configurable PolicerActions

Policer marks or dropsdepending on packet marking

Policing options Port VLAN L3 + L4 ACL based flow

Mark Drop Drop

Mark Mark Drop

Mark Mark Mark

CIR

PIR

EFBEAF

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5


DiffServ Queue ManagementRED/WRED

Two alternatives RED (random early detection) Tail drop

RED efficient with TCP end-to-end flow control withoutexcessive packet loss

Tail drop suitable for real timeapplications and flows withoute2e control (UDP)

Individual setting for each queue

Ave Queue length

100%

Drop Probability

min th max th

max p

Ave Queue length

100%

Packet in Queue

Drop Probability

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5


WRED and Tail DropSettings

100 Mbps STM-1 1000 Mbps STM-16Queue length (ms) 1 1 0,25 0,25Queue length (bytes) 12500 18750 31250 77500

Table 1. Queue length for real-time service class.

Priority Data Business Data Best-effortQueue length (Packets) 150 200 200Minth Green (Packets) 30 30 N/AMax th Green (Packets) 90 90 N/AMax p Green 10% 10% N/AMinth Yellow (Packets) N/A 5 N/AMax th Yellow (Packets) N/A 15 N/A

Max p Yellow N/A 10% N/AMinth Red (Packets) N/A 5 5Max th Red (Packets) N/A 10 15Max p Red N/A 20% 10%

Table 1. RED and WRED settings for a 100 Mbps egress link.RED and WRED settings for a 100 Mbps egress link

Queue length for real-time service class

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5


DiffServ SchedulingStrict Priority and WFQ

SP queues always served first Scheduler takes packets from

each WFQ based relativeweights

If no EF packets to transmit,capacity available for WFQs

1000 queues for per VLANqueuing

Q#0

Q#1

Q#1022

Egressport

#N

Pool of queues

CS7

WF Q

EF

AF1

AF2

AF3

AF4BE

S P

Q#2

Q#3

Q#4

Network ControlReal Time

PremiumData

Services

Best Effort

BE

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

11/21


WFQ Settings

Service Class Queue Rate Scheduling weight r n settingReal-time SP2 B (2) Control SP1 B (3)

WFQ6 (r 6/R)BBest-effort WFQ5 (r 5/R)*B

Priority Data WFQ4 (r 4/R)*B r 4=8000(4)

to ensure low delay.Business Data WFQ3 (r 3/R)*B Reservation of guaranteed bandwidth.WFQ2 (r 2/R)*BWFQ1 (r 1/R)*B

B = port bandwidth, R = r 1 + r 2 + r 3 + r 4 + r 5 + r 6 (1) Minimum rate if the queue is constantly backlogged.(2) Leakage parameter gives transmit opportunities to WFQ.(3) The amount of control traffic is low, so it will not consume all the bandwidth.(4) The value range of weight r = 18000.

Table 1. Weight settings for WFQ. Weight settings for WFQ

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

12/21


Shaping

0

50

100

150

200

250

0

50

100

150

200

250

timetime

B a n

d w i d t h

B a n

d w i d t h

W F Q Egress

Port W F Q Egress

Port

Shaping

Packets sent out immediately accordingto SP/WFQ scheduling if shaping notused

Shaper associated to each queueindependently

Shaping limits packet transmit rates toCIR and PIR

Shaping is optional

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

13/21


DiffServ and ATMTraffic Management

Forwarding decision on ingress line card

Queuing on egress line card Queing for packet and cell traffic DiffServ and ATM scheduling systems

Egress Line Card

IFM

IFM

ForwardingDiffServ

Scheduling

IFM

IFM

5 Gbps

5 Gbps

5 Gbps

14 x 14 x

DiffServQueuesBackplane

Ingress Line Card

ATMScheduling

ATM VCQueues

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

14/21


Tellabs 8600DiffServ QoS Flow

Packet in Packet out

Ingress Egress

Classify Police Queue Shape ScheduleForward

Function Features Benefits

L3/L4 Classification (ACL) Accept/DenyPolicer and QoS

Identify customers and applications.Set bandwidth limits and priority perflow.

Forwarding Decision Based on IP, MPLS, VLAN, Port(routing/switching/tunneling)Support IP, MPLS and L2 (ATM,Ethernet, FR and TDM) applications.

Policing and Marking CIR, PIR, CBS, PBS per servicePacket marking or dropping

Flexible bandwidth options for eachservice.

Queuing RED, WRED or tail dropPacket buffering (queuing)Effective congestion controltechniques.

Shaping CIR and PIR limits Smoothes out traffic bursts.

Scheduling Strict priority and WFQ scheduling Real time, premium data and best effortservices in parallel.

Backplane

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

15/21


Ethernet

Ethernet (DiffServ)Traffic Management

POLICER 1

POLICER 2

POLICER 3

POLICER n

SHAPER

SHAPER

SHAPER

SHAPER

SHAPER

SHAPEREF EF

AF1 AF1

AF2 AF2

AF3 AF3

AF4 AF4

BE BE

Ethernet

Ethernet

PHY ports

Port or VLANgranularity

CIR, PIR, CBS, PBSper PHY port or VLAN

Queue selectionbased on PHY, VLAN

or PRI (802.1p)

Shaping perqueue

Strict priorityscheduling for EF

WFQ schedulingfor AF and BE

PHY port

VLAN

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

16/21


IP (DiffServ)Traffic Management

POLICER 1

POLICER 2

POLICER 3

POLICER n

SHAPER

SHAPER

SHAPER

SHAPER

SHAPER

SHAPER

PHY ports

L3/L4 ACL identifiescustomer and application

CIR, PIR, CBS, PBSper PHY port or ACL

Queue selectionbased on DSCP or ACL

Shaping perqueue

Strict priorityscheduling for EF

WFQ schedulingfor AF and BE

PHY port

ACL 1IP

IP

IP

ACL 2

ACL 3

ACL 4

POLICER 4

EF EF

AF1 AF1

AF2 AF2

AF3 AF3

AF4 AF4

BE BE

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

17/21


Tellabs 8600ATM Traffic Management

Cell inCell out

Ingress Egress

Queue Shape ScheduleForward

Function Features Benefits

Policing PCR, SCR, MBS, CDVT based policingusing GCRA algorithm. Limit bandwidth or mark cells (CLP=1).

Forwarding Decision Based on ATM VPI or VCI. ATM VP/VC switching.

Queuing Per VC or VP queuing. In congestionCLP=1 cells dropped (future).Effective congestion controltechniques.

Shaping PCR, SCR, MBS, CDVT based shaping.

Scheduling

CBR, VBR, UBR+ and UBR outputqueues. Queues are served in priorityorder CBR->VBR->UBR+->UBR. CACper VP.

Guaranteed real time and best effortservices in parallel.

Backplane

Police

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

18/21


VP

VP

VP

ATM Traffic Management

CBR

UBR

VBR

UBR+

VCVCVC

VC

VC

VCVC

PHY

PHY

IngressLine Card

EgressLine Card

Per VC or VPqueuing

Per service categoryoutput queues

ATM IF CAC(Sum of VPs)

ATM VP/VCforwarding

to egress queues

Per VC andVP

scheduling

VP

VP

VP

Backplane

ATM IF110x

Overbooking

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

19/21


DiffServ QoS ParametersSummary

Parameter Function

Minimum policed packet size. Default 128 bytes. If a packet is smaller, the policed bandwidth is calculated with this packet size.

Minimum shaped packet size. Default 128 bytes. If a packet is smaller, the shaped bandwidth is calculated with this packet size.

Policer bandwidth (CIR, PIR, CBS, PBS) Policers defined for EF, AF and BE traffic. Policer can be associated to a port, VLAN orL3/L4 flow.

Policer marker action (mark or drop) for CIR and PIR. Policer can be associated to a port, L2 flow (VLAN, VP/VC, DLCI) or L3/L4 flow.

Define ingress and egress QoS mapping for traffic. IP DSCP/MPLS label/802.1p mapping to EF/AF/BE.

Map packet QoS classes to queues. Enables mapping of one or several QoS classes into single queue.

Strict priority queue leak rate. Optional feature. Scheduling system may give transmit opportunities from strict priority toWFQ scheduling. 1/1 1/250 range.

Queue length. Specify queue length in packets for every queue.

Queue weight. Scheduling weight for WFQ scheduling classes (AF1, AF2, AF3, AF4, BE). Value range08000.

RED/WRED drop criteria. Set minimum and maximum thresholds and drop probability and maximum thresholds.These three values define the drop probability curve that RED/WRED uses for a queue.

RED/WRED exponential weighting factor Defines how quickly RED responds to changes in queue lenght.

Shaper bandwidth (CIR, PIR, CBS) EF, AF and BE shapers associated to physical egress ports. BE shaper can beassociated to VLAN.

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

20/21


ATM QoS ParametersSummary

Parameter Function

ATM IF overbooking Enables up to 10x overbooking of interface capacity. Applies to CBR, VBR and UBR+ service categories.UBR does not reserve bandwidth.

VP service categories Supported service categies (CBR, rt-VBR, nrt-VBR, UBR+, UBR) in a VP.

VP or VC traffic parameters Define service category (CBR, rt-VBR, nrt-VBR, UBR+, UBR), conformance definition (CBR.1, VBR.1,UBR.1), PCR, SCR, MCR, MBS and CDVT for a VP or VC.

atm cell-concatenation Number of ATM cells to be concatenated (132)

VP shaping Enable VP shaping according to PCR, SCR, MCR and CDVT for a VP.

VC shaping Enable VC shaping according to PCR, SCR and CDVT for a VC.

8/10/2019 4_22109-FGC101414_EN_B_PDFV1R5

21/21

4_22109-fgc101414_en_b_pdfv1r5

Documents