Explanation/Reference:
Testlet 1
Case Study
This is a case study. Case studies are not timed separately. You can use as much exam time as you would
like to complete each case. However, there may be additional case studies and sections on this exam. You
must manage your time to ensure that you are able to complete all questions included on this exam in the
time provided.
To answer the questions included in a case study, you will need to reference information that is provided in
the case study. Case studies might contain exhibits and other resources that provide more information
about the scenario that is described in the case study. Each question is independent of the other question
on this case study.
At the end of this case study, a review screen will appear. This screen allows you to review your answers
and to make changes before you move to the next sections of the exam. After you begin a new section,
you cannot return to this section.
To start the case study
To display the first question on this case study, click the Next button. Use the buttons in the left pane to
explore the content of the case study before you answer the questions. Clicking these buttons displays
information such as business requirements, existing environment, and problem statements. If the case
study has an All Information tab, note that the information displayed is identical to the information
displayed on the subsequent tabs. When you are ready to answer a question, click the Question button to
return to the question.
Overview
Tailspin Toys is a toy manufacturer. The company headquarters is located in Melbourne. The company
has a design and development office located in Singapore. The company also has branch offices in Hong
Kong, Jakarta, Tokyo, Sydney, and Auckland. Tailspin Toys has implemented Skype for Business Server
2015 and is actively using instant messaging (IM), presence, peer-to-peer audio and video, conferencing,
remote access, and federation. The company uses Exchange Online. The number of users in each office
is shown in the following table:

Existing Environment
Networks

The network latency between each branch site and the central site is more than 25ms. Based on the
network latency, you use the RTAudio codec for all public switched telephone network (PSTN) calls from
the branch sites.
All Windows desktop client computers run Windows 7, Windows 8.1 or Windows 10 and are domain
joined.
Skype for Business
Singapore and Melbourne each have the following Skype for Business Server 2015 components:
A front-end pool with three front-end servers

A back-end pool that is configured as a two server SQL AlwaysOn availability group

A single Edge server

A single Reverse Proxy server

A single Office Web App server

Tailspin Toys currently uses a third-party dial-in conferencing provider. Moving dial-in conferencing from
the third-party dial-in conferencing provider to the new Skype for Business solution will add a maximum
concurrency of 50 PSTN calls to the Melbourne and Singapore sites, respectively.

PBX and Dial plans
The following table shows the call load for the existing IP PBX solution:

The following table details the Dial Plan for the Sydney office:

User issues
Users report the following issued:
Users in Hong Kong report issues with a media quality when using Skype for Business conferencing

features.
Users who need to use Call Via Work report that this option is not visible in their desktop client.

Users in the Auckland office report issues regarding call quality. You identify that the issue relates to

use of non-qualified devices. You purchase new qualified devices and have delivered the devices to the
Auckland office.
After the migration from the existing IP-PBX, users in Sydney report that they cannot make calls to

mobile numbers.
User1 is located in the Auckland office. User1 reports persistent call quality issues.
You generate the following diagnostic report for User1:
Caller Device and Signal Metrics:


Audio Stream (Caller -> Callee)


Audio Stream (Callee -> Caller)

Requirements
Business requirements
You have the following business requirements:
You must centralize voice services and reduce the costs associated with long distance and

international calls.
You must implement a single voice solution across the enterprise.

Any planned changes to the solution must minimize administrative and financial costs.

Executives must be allowed to use third party tablets and mobile devices.

Executives must be able to receive inbound calls even under bandwidth constrained situations.

Technical requirements
You have the following technical requirements. The new Skype for Business solution needs to replace the
existing third-party dial-in conferencing provider.
Network requirements:
Prioritize Skype for Business traffic on the network where possible.

Avoid over-subscription on bandwidth-constrained network sites.

Unified Messaging requirements:
Tailspin Toys prefers to use voice mail as part of Exchange Online.
Enterprise Voice requirements:
Provide enterprise voice to all users in all location.

Ensure that the solution is highly available.

PSTN connections must be centralized to Melbourne and Singapore.

You must implement Call Via Work functionality for specific users.