150 - ceragon - ip-10g qos intro - presentation v1.6

8/18/2019 150 - Ceragon - IP-10G QoS INTRO - Presentation v1.6

1/13

FibeAir IP-10 G-Series®

Proprietary and Confidential

QoS Concept & Implementation

Agenda

• Introduction

•

• Not all Traffic are the same…

• Traffic Engineering as a solution

• QoS in IP-10

Proprietary and Confidential2


2/13

Introduction (1)

IP-10 is more than a Radio:

–

L2 ETH

SWADM

Up to 500Mbps @ 56MHz

ADM – Add & Drop Multiplexer:It enables a matrix of cross-connections

between TDM E1/T1,SDH VCs andRadio channels


MW

Radio

L2 ETH Switch:• 802.1p/q

• P-Bit remap

• Policers

• Shaping• Scheduler

• IPv4 / IPv6 Classification

3

Introduction (2)

In this presentation we shall focus on the QoS implemented with the

integrated L2 ETH switch

But first, let us understand

what does Quality Of Service

stands for…

L2 ETH

SWADM


MW

Radio


3/13

Understanding QoS

Why do we need QoS? (1)

Without controlling our Backbone /Core infrastructure -

• High cost of non-responsiveness: devices are deployed but not properly

allocated to transport customer traffic

• On the other hand – bad resource design results in congestion which will lead

to network downtime costs due to degradation of performance

• QoS (e.g. - Traffic Engineering) optimizes

network resources



4/13

Why do we need QoS? (2)

Mobile operators focus on reducing costs:

• Mobile Broadband growth requires Backhaul expansions, hence:

• Operators are stretching their cost-saving initiatives

Business center Wireless Carrier Ethernet

Backhaul Network

• Operators will look for new ways to drive further Backhaul savings

• Operators must reduce their cost per Mbit

• QoS (e.g. - Traffic Engineering) optimizes network resources


Hub / Aggregation site

WiMAX / 4G / LTE

Cellular site

WiMAX

Ceragon

2G/3G base station

Ceragon

TDM

E1/T1

STM-1 / OC-3

GE

Fundamental Fact

Static

WWWDynamic

WWW

Multimedia

Not all traffic is the same!Skype

FTPemails


So why treated equally?...

8

Who’s

first?


5/13

Traffic Engineering as a Solution

Static

WWWDynamic

WWW

Multimedia

Your 1st assignment is identifying needs & solutions:

What is the BW requirement per service ?

• Video requires more than voice

Skype

FTPemails

• a a requ res ess an v eo

• FTP requires more than emails…

What is the delay sensitivity of each service?

• Delayed Voice is inacceptable…

• FTP can tolerate delays

Your 2nd assi nment is rou in services into SLAs:


• Video & Multimedia – Low Services (Best Effort)

• FTP – Moderate Service

• Skype – Highest Service

Your 3rd assignment is con figuring QoS in your network

QoS in IP-10


6/13

IP-10G L2 ETH Switch Ports

The IP-10G’s L2 Switch has 8 ports:

• Port #1 GbE (Opt. / Elec.)

• Port #2 GbE (Opt. / Elec.)


• Port #3 to port #7 FE

• Port #8 (Radio port)

11

QoS Process

Q4

Q3Q1

Q4

10 50

25

Ingress Port Egress Port (s)

Rate Limit Queuing Scheduling Shaping



7/13

Ingress VS. Egress

Every Switch port applies Ingress Rules and Egress Rules depending on traffic

characteristics (L2 header and applied policies)

Provider

Network

Customer

Network

Ingress

port

Egress

port


Provider

Network

Customer

Network

Egress

port

Ingress

port

Ingress VS. Egress: IP-10

Radio port (ETH port #8):• Ingress traffic relates to traffic received from remote IDU

• Egress traffic relates to traffic sent to remote IDU

Non-Radio ports (ports 1 to 7*):

• Ingress traffic relates to traffic received from customer • Egress traffic relates to traffic sent to customer

*

Ingress

Egress


Radio

Port 1-7*

Radio

or -

Ingress

Egress

* Ports 7, 6 & 5 can be used as management or data


8/13

Ingress Rate Limiting

Users can configure maximum ingress rate per port

Exceeding traffic will be discarded

Rate limitation can be configured per type of traffic (Policers)

25

FE Max.

Rate

Discard

100Mbps

Max. Allowed


Actual

Customer

Traffic

Time

Pass

Example: Policer assigned to FE interface

Rate

Using Queues

Every port of the L2 switch examines the ingress traffic and then it sorts it in a

buffer according to classification criteria

Users can configure up to 4 queues where Q4 has the max. priority and Q1

has the lowest priority

Q4 High


Q3

Q2

Q1 Low


9/13

Using Queuing


Scheduling (1)

Once the queues are filled with information, we need to empty them

Which queue should we empty first?

Round-Robin:

Emptying cycle is fixed – all queues are treated equally

Q4 High


Q3

Q2

Q1 Low

Q2Q1

Q4Q3Q2Q1Q4Q3Q2Q1

Pro: no “queue starvation”

Con: no prioritization


10/13

Scheduling (2)

Weighted Round-Robin:

Emptying cycle is configurable – every queue can be given specific weight

Q4 High

44


Q3

Q2

Q1 Low

Q3

Q2

Q1 Q4Q4Q3Q2Q1Q4Q4Q3


Scheduling (3)

4th Strict Priority:

The switch will empty Q4 as long as it has something

–

If Q4 receives a frame during the Lower-Queues-RR, it will go back to focus

on Q4

Q4 High


Q3

Q2

Q1 Low

Q3

Q2

Q1Q4Q4Q3Q2Q1Q4Q4Q3

Pro: Optimized Prioritization

Con: “Queue starvation”


11/13

Scheduling (4)

All Strict Priori ty:

The switch will empty a queue as long as the higher queue is empty

Q4 High


Q3

Q2

Q1 Low

Q4Q4Q3Q2Q1Q4Q4Q3


Shaping

Bursts beyond a EIR (Excessive Information Rate) can be buffered and

retransmitted when capacity frees up, and only when shaping buffers are full

will packets be dropped.



12/13

Possible Scenarios

Radio

Port 1-7*

Radio

Port 1-7*

Ingress

QueuingRadio Egress

Scheduler =

No need for

Ingress Queuing

No need

for E ress


Strict Priority Scheduler

Possible Scenarios

Radio

Port 1-7*

Radio

Port 1-7*

Ingress

Queuing

Radio Egress

Scheduler =

Ingress Queuing is

required in port 8

Egress

Scheduler


Round Robin

is required


13/13

Thank You !

25

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150 - ceragon - ip-10g qos intro - presentation v1.6

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