Microsoft® Lync™ Server 2010Network AssessmentModule 14

Microsoft Corporation

Session Objectives and Takeaways

Session Objectives: • Describe the goals of a Network Assessment• Discuss and Understand key elements of a Network

Assessment• Understand how traffic simulation tools are used• Demonstrate the Microsoft Lync Server 2010 Bandwidth

Planning tool

Takeaways: • Network Assessment reduces overall project risk• Bandwidth Calculator is key for usage modeling

2

Agenda

• Network Assessment Overview

• Network Assessment – Phase 1: Discovery

• Network Assessment – Phase 2: Usage Modeling

• Lync Bandwidth Calculator Overview

• Lync Bandwidth Calculator Demo

• Network Assessment – Phase 3: Traffic Simulation

• Network Assessment – Phase 4: Recommendations

• Sample Network Assessment Site Reports

3

4

Network Assessment Customer benefits

Validates an Enterprise’s

Readiness for Unified

Communications (UC)

Quantitative assessment of

current Infrastructure

metrics that impact UC

Reduces deployment risk

Highlights areas that might impact

UC readiness

5

Network AssessmentWhat is a network assessment?

Discovery Session Understand what network environment exists

Usage ModelingModel proposed bandwidth using user profiles and usage patterns

Traffic SimulationUsing a UC Traffic simulator, apply real traffic to production network and monitor factors that affect the quality of UC traffic, Delay, Jitter, and Packet Loss

RecommendationsAnalyze factors affecting quality and produce a full report with recommendations

6

Discovery

7

Network AssessmentDiscovery phase: information collection

Network Assessment

QoS Policies Network Topology

Network Utilization

Levels

Regional WAN Bottlenecks

Firewall Architecture

• Is QoS in place? • Is there WAN QoS? • Are the WAN SLAs? • Max Percentage of

links you can reserve for UC Traffic?

• How many sites to you have?

• Describe Layer 2 and Layer 3 resiliency.

• Do you log current utilization levels?

• Are there multiple WAN providers? Regional bottlenecks?

• Discuss your firewall architecture e.g. internal firewall and external firewall

Required Network Information

• Existing traffic levels on each remote site• Max peak level over last 3 months• Busy hour average traffic

• QoS Policies• Bandwidth allocations, queuing methods

• Network Topology• Star topology, INTER-SITE links, regional

bottlenecks

8

9

Usage Modeling

10

Why Do You Need To Understand Usage Model?

• The point of the network assessment is to generate “realistic” simulated UC traffic

• You need to collect enough information to know two things: • Where do I place my simulation endpoints?

• How much traffic should I generate?

Typical Questions

• How much bandwidth does a call need? • Does my WAN have enough bandwidth ? • Can I place my conferencing pool

overseas?• Are there standard usage models?

11

Planning Goals• Provide WAN impact for branch sites, and WAN impact on

data center sites of branch users• Provide traffic modeling for use during network engineering

• Understanding of call flows and bandwidth usage• Provide business with information needed for network

capacity planning

12

Required User Information

• Number of user per site• Modalities in use by those users• User usage statistics – if any exist

• Conferencing usage• PSTN usage• We provide a starting point if none exist

13

Bandwidth – PlanningMedia Modality Codec Typical BW Max w/o FEC Max w/FEC

Audio Peer-to-Peer RTA-W 39.8 62 91

Audio Peer-to-Peer RTA-N 29.3 44.8 56.6

Audio PSTN RTA-N 30.9 44.8 56.6

Audio PSTN G.711 64.8 97 161

Audio Conferencing G.722 46.1 100.6 164.6

Audio Conferencing Siren 25.5 52.6 68.6

Video Peer-to-Peer RTV - CIF 220 260

Video Peer-to-Peer RTV - VGA 508 610

Video Peer-to-Peer RTV - HD 1210 1510

Video Peer-to-Peer RTV - Pano 269 360

Video Conferencing RTV - CIF 220 260

Video Conferencing RTV - VGA 508 610

Video Conferencing RTV - Pano 269 360

One-way traffic including media, typical activity, RTCP.

For planning in a well managed, right-sized network, use Max BW w/o FEC

If the network will be constrained and you want to preserve quality, use Max BW with FEC

When understanding how much bandwidth at any given time is being used, use the Typical BW numbers. Not for planning, as usage will be greater at times

14

What About Application Sharing Traffic?• Bandwidth used by application sharing is highly dependent on session

content and screen resolution• Traffic is bursty in nature

• Zero in ‘steady state’, spikes • On slide transitions, etc.

• Transmission Control Protocol (TCP) based sessions• In-built congestion control

• End user policy limits available to cap spikes19:21.100:36.141:51.111:36.144:21.125:36.106:51.10

500100015002000250030003500400045005000 Kilobits/sec sent by

Sharer

Screen size Acceptable Optimal

1280x800 384 Kbps 1.5 Mbps

1440x900 512 Kbps 2 Mbps

1680x1050 768 Kbps 2.75 Mbps

1920x1200 1 Mbps 3.5 Mbps

15

Calling Scenarios – Usage Modelling

• Core call flow scenarios to consider for network planning calculations• Conferencing usage

• Which modalities? • Client MCU

• PSTN calling • Client Mediation Server

• Inter-site peer-to-peer• Which modalities?

16

17

Bandwidth Calculator

Output Overview

 

18

Calculator – Input Flow Chart

19

Modalities Handled by Bandwidth Calculator• SIP signaling: instant messaging, presence

subscription and signaling traffic• Inter-site peer audio• Inter-site peer video• Inter-site peer application sharing • Conference audio• Conference video• PSTN audio

20

21

Example Customer for Calculator Demo

WAN

Phoenix Central Site• WAN link: 32 Mbps• Users: 26,000• Users with PSTN:

50%

London Central Site• WAN link: 10 Mbps• Users: 16,200• Users with PSTN: 50%

Tucson - Branch• WAN link: 10 Mbps• Users: 8,000• Users with PSTN: 100%• Remote users: 30%

Leeds - Branch• WAN link: 10 Mbps• Users: 8,000• Users with PSTN: 100%• Remote users: 30%

Small Branch Sites• WAN link: 2 Mbps• Users: 20• Users with PSTN: 100%• Remote users: 0%

Demo: Bandwidth Calculator

22

23

Traffic Simulation

24

Mapping Lync Media Flows

PROBLEM STATEMENT: • NetIQ Vivinet Assessor only supports G711, G729

• No support for RTAudio / RTVideo Codec simulation

SOLUTION: • We take the “Total BW” for each Call Flow in the

previous step. • Calculate how many G711 calls are needed to

simulate that value

25

Mapping Example

• We know that G711 (without VAD) is 92Kbps on the Wire. • 1800 / 92 = 19 Calls (G711) for Peer Traffic• 10,000 / 92 = 108 Calls (G711) for Conferencing Traffic • 5,000 / 92 = 54 Calls (G711) for PSTN traffic

Peer to Peer (WAN)

Conferencing PSTN

1800 Kbps 10,000 Kbps 5,000 Kbps

Endpoint Datacent

er

Endpoint Site A

EndpointSite B

54 Calls

108

Calls

108 Calls

54 Calls

19 Calls

26

Configuring Tool

Endpoint Datacent

er

Endpoint Site A

EndpointSite B

54 Calls

108

Calls

108 Calls

54 Calls

19 Calls

Scenario Endpoint 1 Endpoint 2 Number of Calls

Conference - Site A

SiteA Datacenter 108

Conf/PSTN - Site B

SIteB Datacenter 108

PSTN Calls - Site A

SiteA Datacenter 54

PSTN Calls - Site B

SIteB Datacenter 54

Peer - Site A- Site B

SiteA SiteB 19

Screen Shot from Tool

27

Network AssessmentTraffic Simulation Goals

• Run real UC traffic across your network• Ideally for 7 days, 24hrs/day.

• Collect accurate metrics for factors that affect UC Readiness• Delay• Packet Loss• Jitter

• Report on metrics on a Per Site, Per Call basis to understand where, and when UC calls were affected by adverse conditions

28

Recommendations

29

Network AssessmentRecommendations• Pull together all elements to form a “UC Ready”

decision against your current Network Infrastructure• Present a full list of areas within your existing

infrastructure that might impact UC• Examples:• No QoS Implemented• WAN links under-provisioned for predicted traffic levels• Location of proposed Data Center for Lync server 2010

introduces too high a Delay for users in another region (European DC, servicing APAC users)

30

Highlights per Site• Houston to Runsor

• Four calls between Houston and Runsor• Virtually no variation in delay or call quality

31

Highlights per Site• Houston to Guatemala

• Two calls between Houston and Guatemala• Huge variable delay during local working hours • Unloaded link it suitable for UC Traffic, but requires some type of WAN QoS

implemented to deal with traffic prioritization.

32

Highlights per Site

• Shanghai to Toyama• Two concurrent calls simulated• Huge variable delay during local working hours

33

Q&A

© 2011 Microsoft Corporation.  All rights reserved.  Microsoft, Windows, and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries. The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation.  Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation.  This document may contain information related to pre-release software, which may be substantially modified before its first commercial release. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED  OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION. Unless otherwise noted, the example companies, organizations, products, domain names, e-mail addresses, logos, people, places and events depicted herein are fictitious, and no association with any real company, organization, product, domain name, email address, logo, person, place or event is intended or should be inferred.