A Profitable Hybrid Desktop as a Service Solution

Manish Dhall and Qing Tan

School of Computing Information Athabasca University

Athabasca, Canada

manishdhall@outlook.com and qingt@athabascau.ca

Abstract — Corporate IT is aggressively seeking their daily

needs of cloud-based services on “Pay-As-You-Go” (PAYG)

basis. Various cloud vendors (Microsoft, AWS, IBM, Google

etc.) have their various structured cloud services offer focusing

on cloud basic services. Building an innovative solution using

one deployment model with the use of various cloud service

models has been challenging. Various service providers (SPs)

including Hosting Service Providers (HSPs), Managed Service

Providers (MSPs), Telecommunication Companies (TelCos),

Independent Software Vendors (ISVs) see these big gaps as a big

monetizing opportunity with Small Medium Business (SMB)

customers. SPs have built competitive business models with

PAYG approach in leading this space of innovatively creating

the customized solution offers using cloud computing hybrid

model. “Desktop as a Service” (DaaS) solution is well received

offer among SMB customers across multiple industry verticals

with compliance requirements. A cost estimation model with

reference architectures is discussed with various economy model

for the solution. In this paper, we will present a profitable

hybrid Desktop as a Service (DaaS) solution.

Keywords—Desktop-as-a-Service (DaaS), Virtual Desktop

Infrastructure (VDI)

I. INTRODUCTION

Desktop as a Service (DaaS) provides a virtual desktop & virtual application environment for the consumers with the compliant regulations. Consumers can access the full DaaS using thin clients with remote desktop protocol, iPad, or mobile phone. DaaS environment is built in hybrid cloud using IaaS & PaaS cloud services. Service Providers innovatively build the solution using cloud strengths with monetizing opportunities in up-sell and cross-sell. This becomes a success scenario for all the stakeholders. An appropriate balance on the use of cloud technologies is essential in building a competitive solution offer. This paper will add value on various aspects of meeting these challenges for the stakeholders; listed below.

• Hybrid cloud solutions model provides strengths from multiple cloud services. At the same time, it opens various aspects of using multiple solution in the right capacity to build solution offer economically and competitive.

• SMB Customer’s biggest challenges are to invest heavily on IT for innovatively creating the customized solution using various cloud services using PAYG model.

This paper’s goal is to explore and develop the guidelines on how cloud service providers can build a customized cloud solution offers virtual remote desktop and virtual remote application to the consumers on pay as you go model. This helps service providers to

run their business more profitable at the same time benefits for consumers is to avoid big investments in IT for their small to mid-sized businesses without compromising on business’s IT needs.

Consumer demands give the birth of new innovations driving cloud vendors (Microsoft, AWS, IBM, Google etc.) service offers focusing on cloud elemental services. Building an innovative solution using one deployment model with the use of various cloud service models has been challenging. SPs have built competitive business models with PAYG approach in leading this space of innovatively creating the customized solution offers using cloud computing hybrid model. “Desktop as a Service” (DaaS) solution is well received offer among SMB customers. This paper will explore the opportunities of building an economical DaaS solution with various cloud service and deployment models.

Positive outcome of this research work will primarily provide benefits to the stakeholders.

• Service Providers will gain additional insights in building a measured profitable DaaS Solution using Microsoft cloud technologies for increasing their revenue from SMB customers.

• SMB customers with expensive and complex compliance requirements need in successfully running their business without compromising the compliance & regulatory requirements breach; will be able to consume the solution in timely scale perspectives on PAYG model.

Potential negative outcome of the research work in primarily focusing on Cloud Computing usage listed below.

• With the release of this research, SPs will be able to build a secure, compliance multi-tenant solution offering. This can be taken as a threat to some Cloud Vendors (AWS) and bigger ISVs (CITRIX, VMWare) in the market with existing offers at expensive price tags. solution

Next, we will provide our review of literature on DaaS and the market. Then we present a profitable hybrid desktop as a service solution in section 3. Furthermore, we will discuss the conclusion will be exploring and comparing with rationale on the various approaches in building the profitable, secure and complaint Hybrid DaaS Solution for Service Providers.

II. REVIEW ON DAAS AND THE MARKET

For this research, we extensively reviewed the literature published recently in 5 to 6 years. These including general paper articles, IT conferences proceedings; primarily from research databases (IEEE), technology blogs, various vendor’s & service provider’s current websites, United States government publishing, US government IT standards institutions & organizations (NIST, PCISecurity, FedRamp, HIPAA, PCI, US federal commission),

Industry business magazines (Forbes), market intelligence research & advisory agencies (IDC, Gartner, 451 Research). We found that there is little academic publication on this topic of building the DaaS solution for MSPs. DaaS has evolved from VDI, a traditional on-premises IT infrastructure serving virtual Desktop and virtual remote applications [1]. Typically, VDI is built to serve the same functionalities for enterprise customers with the on-prem datacenter infrastructure running the VDI servers. There are plenty of vendors offering the VDI services in the market, among those VMware and CITRIX have the stronger position. Microsoft technologies to build the DaaS solution is considered one of the foundational and strongest technologies in the cloud. SPs are extending the DaaS solution with additional features and 3rd party vendors applications and tools to make their business more profitable while meeting the end consumer customized requirements.

A. Overview of Cloud Computing

In 2006, Cloud computing word was first introduced by Google CEO Eric Schmidt in an industry conference [2]. Following this period bigger IT companies like Amazon, Microsoft, IBM started taking advantages of the new Cloud Computing shift by aligning their product line with the cloud computing. For the first time in 2011, a formal guideline of the cloud computing was released by National Institute of Standards & Technology (NIST) [3].

Virtualization is one of the factors help enhancing the cloud computing infrastructure [4]. Virtualization helps making appropriate usage of the Hardware (Servers, Storage, Network), software (Operating System, Hypervisor) in providing the server consolidation, isolation, encapsulation, hardware independence, cost reduction etc. with the required cloud computing essential characteristics but also can support various service models and deployment models.

B. Managed Solution Offers by Service Providers

Microsoft, Amazon, IBM, Google etc. started investing very heavily in building the cloud service. Service providers stepped in to build their cloud offerings based on cloud services. The cloud offerings are consumed by the end customer/organization in form of the cloud subscription in PAYG model supporting subscriber’s day-to-day requirements [5].

C. Service Providers value-add

Using out of the box cloud vendors offering may require additional efforts of installing Line of Business (LOB) Applications with further deeper customization for the business needs. Gathering the requirements and implementing the right solution appropriately to meet the business requirements can be achieved by an individual or team of IT professionals. Managed Services helps SMB sized customer in leveraging the cloud computing with the appropriate scale & agility [6]. Managed Service provider works with Out of Box (OOB) cloud offers from cloud vendors to customize for their customer’s business and technical requirements.

Smaller to bigger businesses are looking forward to move away from their inhouse IT to IT-as-a-service model for their organization [7]. Service Providers are filling up the gap of building the right solution by customizing the various cloud services deployment and service models. In some cases, Service providers are using multi cloud approach [8] for using the “best of all world” scenarios to provide the customized solution to the end customer. Managed Service Providers add a great value resolving the issue of added complexity in building the appropriate solution for the customer [9].

D. Desktop-as-a-Service (DaaS) – A Deeper Dive

This shift in the cloud computing paradigm with the addition of Service Providers contribution is exploding the tremendous amount of cloud services to “as-a-service” model approach [10]. In the traditional IT world, it has been known as VDI; with the shift in cloud computing with added cloud characteristics the new name is Desktop-as-a-Service (DaaS) [1]. DaaS has become a very well received recognition among various industry verticals including healthcare, retail, public, commercial, government etc. A

questionnaire-based survey from the users of German Ministry of Justice has expressed the success model of DaaS with the capabilities of a good rich feature sets including accessibility, consistency, flexibility, reliability with elevated compliance security and regulatory governance [11].

Building a productive DaaS solution requires a careful planning, designing and benchmarking for performance of the solution [12]. DaaS is very helpful for the business organization to avoid bigger CAPEX investments with the lower Total Cost of Ownership (TCO). The demand of this solution offering has become very popular among the business owners for their organizations; driving the Return of Investment (ROI) higher [13]. DaaS enable the organizations with the rich functionalities feature sets.

Building the DaaS solution is complicated. The paper [14] guides through the appropriate selection of the hardware configuration to meet the requirements of the different type of workloads hosted in DaaS deployment with the required performance. Article [15] does reflect solution for meeting the performance requirements in multi-tenant environment for DaaS. Another interesting approach of building a multi-tenant solution using Linux distribution with VNC and SSH tunneling reflects the lower TCO and good performance [16] for the education vertical customers. One of the examples discussed in the article is to use open stack dashboard for managing the DaaS deployment with the solution addressing the audio redirection [17]. End-user requirements are not only limited to audio redirection but exceed the functionalities at higher performance.

Gartner published a report as a market guide for DaaS [18]. Key findings from the report does reflect the adoptability pattern of DaaS Solution by the consumers with various sized organizations with the need of available feature services and the support of today’s IT infrastructure platform with access devices and tools used by end consumers.

E. Competitors in the market

Bigger players in the competition are Microsoft, Amazon, CITRIX, VMWare, Google, HPE etc. There are several service providers, Managed Service Providers (MSPs) and Independent Software Vendors (ISVs) customizing their DaaS solution offers with various cloud services. Service providers primarily categorized in MSPs & ISVs category. MSPs including dinCloud [19], ironOrbit [20], Ace Cloud Hosting [21], Dizzion [22], Insynq [23], Cloudnine [24] usually have very similar desktop solution offers with some distinct capabilities.

Epic being a leader in healthcare vertical as an ISV, is providing their software using the program; Community Connect [25]. Right Networks is a leader in US market for providing QuickBooks, an accounting software [26] as an ISV. Sage [27] is another example offering various business applications including accounting, financials, enterprise management, people management, payroll, payment & banking as an ISV. Appdirect [28] is an ISV offering the virtual applications to various verticals and sectors including manufacturing, financial, IT< marketing, retail, sales etc.

Gartner’s market guide [18] projects a good picture of isolating the multiple components play in building a fully functional DaaS solution offering as compared to the traditional VDI infrastructure. DaaS solution providers can primarily be divided in three main categories based on their IP and solution strength.

• First, Traditional VDI vendors Citrix [29] & VMware [30] taking leads in offering the DaaS solution.

• Second type of category is driven by Service Providers (MSPs & ISVs) working with the cloud vendors in building the customized DaaS solution offers for the end customer’s need. Gartner’s market guide [18] listed few bigger SPs Chromotif [31], CloudJumper [32], Liquit [33], Ericom Software [34], itopia [35], LISTEQ [36], Nerdio [37], Parallels [38], TetherView [39], and tocario [40] driving the DaaS solution market space.

• Third category projects on the DaaS solution offers by the cloud vendors and service providers with the proprietary model approach. Amazon [41] and Frame [42] are the two primary exemplary DaaS Solution vendors.

F. Market needs

One of the driving factors is the hybrid cloud solution offers from the MSPs & ISVs using various combinations of service & deployments models using multi cloud approach. As a result, ISVs are trying to get in to the market of MSPs and vice versa [43]. The article reflects the various aspects of solution management tool sets with platform integration aspects. Service Providers are measured against various Service Level Agreements (SLAs) on the service offerings with the raised expectations for downtime, uptime, customer support availability, performance of the offer, access response time with lower latency [44].

Another market need is higher trust expectations from the service providers. Various trust framework work is discussed in the articles [45]. Applicability of these trust models may varies depending upon several factors including relationships of service providers with other cloud computing vendors. An interested approach of using Trusted Third-Party ranking system is discussed in this paper [46]. These ranking processes need to be very independent without under any influential forces and bodies. To keep it comparative for ranking, there can be a few multiple of these ranking systems. As an example, consumer credibility is measured by credit score system in USA [47]. One example of virtual desktop with high end GPU support for 3d CAD applications is a basic requirement for the architects [48] is very common market need. CITRIX is known to be a leader in DaaS space [49]. DaaS solution help BDMs to minimize the CapEx & OpEx with better budgeting projection for their business. Integration of SaaS & LOB applications virtually made available on any device without any limitations. Service provider can easily support a compliance HIPAA [50], PCI [51] & FEDRAMP [52] customers with meeting the security & regulatory requirements. CISCO has teamed up with Citrix and VMWare [53], using best of all to build a rich DaaS solution. Gartner reported [18] a trend of DaaS solution acceptance and adoptability across the industry verticals with three choices preferences by customer volume.

G. Service Provider Opportunities

Service providers are usually lead in launching the new solution offers in the market. This will give them plenty lead runway as compared to the competition in the market. This business practice does come with few challenges. Not all usable technology in building the solution is offered by the same cloud vendor. SPs partners with cloud vendors very tightly for innovatively building a cloud solution. This approach requires deeper customization. Forbes article reflects the voice of the customers as “Building cloud services is harder than it should be.” [54]. Proposed Common Goal Partnering (CGP) model does emphasize on the collaborative practice of solution offers building by SPs with CVs.

Microsoft has partnered with IDC [55] and released series of 5 e-books [56]. The first book in the series [57] discusses various cloud industry data based on past and current trends around the current cloud industry. More than 750 SPs partner (across the world), survey was conducted reflecting very interesting qualitative and quotative data points on the cloud spending, adoption and future planning.

IDC report on public cloud growth [57] is clearly showing six times the of IT spending across worldwide. Gartner released the supporting facts stating cloud market will hit $500B by 2020. IDC predicted the cloud spending to go over $500B by 2020. Combined cloud services (IaaS, PaaS & SaaS) market will reach $141.28B USD shown in table 1.

Table 1: Public cloud spending growth

Tremendous growth of SaaS offering over combined additions of IaaS & PaaS by 2019 is projected in the IDC forecast shows very interesting facts of the cloud maturity models in these areas shown in table 2. This interesting variation also directly influenced by cloud eco system maturity level. IDC also reports the significance swing towards optimized cloud going forward, in very short time.

Table 2: Cloud Services Forecast

IDC reported the trend of majority of businesses are focusing more on LOB applications, as compared to traditional IT approach of in-house IT. Organizations adopting the LOB application onboarding to cloud will need help from the service provider, who understands the cloud services deeply, and can customize the cloud offering deeply with their LOB Application shown in figure 1.

Figure 1: LOB Application Funding Trends

Managed Service Providers have been continually adding very healthy growth in the cloud solution offering year-over-year. Per 451 Research “Managed services revenue, for both multi-tenant and single-tenant cloud offerings, is growing 60% faster than revenue from infrastructure-only services” [58]. Managed Service growth is significant from $17B USD in 2014 to $130B USD in 2018 with a tremendous amount of opportunities in providing the managed services shown in figure 2.

Figure 2: 451 Research, Market Monitor: Cloud Computing-

Worldwide Managed Services 2014-2018

H. End Customer prospective

As the cloud opportunity is growing bigger, end customers have started realizing the importance and with the maturity in cloud services; it is not anymore, the unknown territory for the end consumers. Application ecosystem is all around the customers. IDC released the snapshot of the landscape for the customers perspective of adopting the cloud [57]. This opens a huge amount of opportunities

for the Service Providers, and consumers gets their confidence build more in cloud adoption with the guided approach of service providers shown in table 3.

Table 3: Cloudview & Average IT Budget

I. Service Provider’s Profitability

IDC report [57] has been projecting over several years with the better growing revenue and profit margins for the service providers, where the SPs have clear focus on cloud offerings shown in table 4.

Table 4: Cloud Revenue & Distribution of Partners

Service providers aligning their business model with the cloud solutions tends to have 2x growth and 1.5x growth margins as compared to the service providers who have no or less focused on the cloud solution offerings. Focusing the solution offerings around the cloud computing will help build more SKUs with the solutions as compared to building the solutions with non-cloud infrastructures. IDC studies reflect service providers with 3 years and more experience in cloud offerings are performing better than those with less than 3 years with the cloud adoption shown in table 5.

Table 5: Gross Profit & Revenue Growth

Scale & repeatability of the solution is one of the biggest strength of the service providers business model. Cloud solution offering help SPs build this model at very fast pace, with better customer service and uptime for the customers. IDC research reflects that more than 50% of the cloud revenue is due to the capabilities of these strengths. As a result, IDC published the cloud solutions growth % with the inclining recurring revenue by cloud adoption shown in figure 3.

Figure 3: Recurring Cloud Revenue

Consumers are getting more mobile with the capabilities of the fast internet access on their mobile devices. Technology is empowering the smaller devices with the innovative solutions to achieve bigger tasks. IDC research [57] shows that “Spending on Smartphones and Tablets was approximately $520B USD in 2015, over 2X the Enterprise Hardware market, and almost 1.2X the Enterprise Software market”. One answer to all of requirements is Desktop as a Service. DaaS solution can be built using various vendors’ products and services. At the same time the cost of building

the solution could go higher and making this economically affordable to the end consumer will be more challenging. Service provider’s profitability will align with the complexity and costing of building the solution.

III. TRENDS, OPPORTUNITIES & CHALLENGES

SMB organizations have launched their production environments on the DaaS solution where as large enterprise organizations have been evaluating this solution in dev/test and semi-production environments [18]. Primarily DaaS solution is built and sold by Managed Service Providers. Building and launching this solution in productions does require quite a bit of work on cloud services with 3rd party vendor solution integration. With this added complexity in building the DaaS solution, end consumer is seeking the complete solution in the virtual desktop availability.

A. Trends

Gartner has published the market research [18], reporting the required attributes with the essential enhancements. SPs are expected to host the DaaS solution in the cloud as a solution offering with additional add on cloud services on PAYG model. Additional

foundational services as (Stock Keeping Unit ) SKUs are listed as business continuity, data management, access control, personalizing, workspace provision automation, compliance security, performance, application lifecycle management etc. within economical cost. OPEX (?) is winning over CAPEX (?) model approaches. Provisioning and management toolsets need to support multiple customer at one time without compromising the privacy by keeping the environment’s management in isolation with least cost confusion for consumers. Solution must have the capabilities of reporting daily or hourly usage cost for consumer to pick the right tier solution with added feature SKUs for their customized needs. SPs are also offering the discounted price for the long term contracts also. Typical contract age is 2-3 years, with the flexibility of revisiting the terms annually after analyzing the average usage pattern of the past year.

B. Multitenancy

Multitenancy severely impact the costing and compliance of the solution. As of today, DaaS solution infrastructure needs to be deployed separately for each organization also known as one tenant with the cost for the static DaaS infrastructure servers. These additional servers supporting the DaaS environment for each tenant adds up big cost to the tenant. This cost cannot be avoided for the tenant’s subscription irrespective of number of end user devices accessing the environment. Multitenant support can solve this issue by sharing the DaaS infrastructure servers among multiple tenants, without compromising the privacy and security. Multitenancy also help completing the regulatory compliance requirements. Solution needs to support the variety of internet bandwidth requirements w/o affecting the performance and latency on the LOB applications. It also depends upon the tolerance of LOB application on the latency throughput. Well written LOB applications allows to be run over the higher latency links without getting broken.

C. Dynamic Scaling

Users usage pattern varies in 24 hours day. Normally it is observed that load on the it infrastructure is very high during the start of the day, slowing down during lunch hours and with one additional spike of load before end the work day. Over the evening infrastructure usage is very light, and during the night it is almost with no load. DaaS solution offer in the cloud should be intelligent enough to automatically scale down or scale up by shutting down and starting the application and infrastructure virtual machines; aligning the usage patterns. End-user cost pricing will be tweaked and aligned for its actual usage not for keeping the lights during the time, no one is using the environment.

Elasticity in the DaaS solution environment plays an important role in automated provisioning and de-provisioning the virtual machine to meet the workload demands. The scenario is one of the perfect examples of making use of 3rd party vendor toolsets [59] for faster provisioning.

D. Compliance

Last but not least is the solution to meet the various regulatory Compliance. Basic requirements of most of the compliance are very similar with the added specialized requirements of specific compliance including FedRAMP, FISMA, ITAR, HIPAA, HITECH, ISO, PCI DSS, SOX, SOC and recently introduced GDPR [18]. Based on the geographical distribution and coverage, these requirements can be complex with the newer opportunities for SPs.

E. Understanding TCO and ROI

Total Cost of Ownership（TCO） can vary depending upon

various factors including number of users in the DaaS deployment. Gartner published report [18] variance of the price of the solution primarily depends upon the features available in the DaaS solution offers. Various contributing factors in the costing of the DaaS solution on per user per month is based on the shared or dedicated virtual machine with the additional capabilities of BYOL for end user devices. There is an interesting swing noticed in last two years in the DaaS offering prices based on features availability. The average pricing per user per month with available feature sets may range from $20-$23 USD per user per month.

Table 6: Change in DaaS Pricing (lowest) in last 2 years

The price swing has severely affected the variation for the specialized high performing DaaS offers. Users demanding higher performance in GPU, requiring dedicated virtual GPU for the user’s specialized ap with graphics rendering, will jump the price up to $600 per ser per month; hiked the price on the higher side, almost double as compare to the price two years ago.

Figure 4: Change in DaaS pricing (highest) in last 2 years

Calculating the TCO for DaaS Solution also require to add more cost around data migration required for DaaS solution onboarding, administrative labor etc. Cost saving should not be the reasons and criteria for selecting the DaaS Solution offer as compared to VDI or traditional Desktop approach.

F. Microsoft DaaS vs Vendors in the market

Per Gartner’s market research [18] on the DaaS vendors and service providers it is clearly projected that Microsoft RDS is one of the best among other competitor vendors for building DaaS solution offer; meeting the most discussed facts with economic cost for per user per month basis.

Figure 5:Comparison of DaaS Providers

DaaS vendors listed by Gartner have very interesting combinations of feature sets and strengths. Per Gartner report, AWS (www.amazon.com) [60] offers persistent and non-persistent state of desktop virtualization. Customers have capabilities to bring their own licenses with extending their existing directory providing multi-factor authentication. Customer can use AWS’s proprietary encrypting mechanism for data at rest, supporting various compliance requirements. This definitely adds the capabilities of basic virtual desktop offer, as compared to the customer requirements of using the productivity suite including word editor, spreadsheets etc. from Office 365 suite of products (www.microsoft.com). CITRIX (www.citrix.com) is capable of providing management and provisioning toolsets for the Microsoft RDS deployments and VMWare VDI solutions. Image creation is one of the most popular toolset CITRIX brings to the DaaS eco system. At the same time, CITRIX relies on Microsoft & VMWare to provide the required functionality, discussed earlier; for completing the DaaS solution. Cloudalize’s (www.cloudalize.com) specialize in providing high performing GPU supported virtual Desktop w/o minimum user requirements with one monthly price. Cloudalize definitely adds a huge additions in the DaaS solution eco system using Microsoft & Citrix based infrastructure. dinCloud (www.dincloud.com) is another service provider using Microsoft and Citirix based DaaS solution with compliance requirements. dinCloud does extend the virtual desktops with productivity suite of software (Office 365 & G Suite (www.google.com) ) from Microsoft and Google with an additional add on of Sap in the virtual desktop for end consumers. Dizzion’s (www.dizzion.com) DaaS solution is based on Citrix and VMware. Customers with the compliance requirement can also use Office 365 and GSuite with the solution to complete the virtual desktop offer. Evolve IP (www.evolveip.net) has its DaaS solution offer built with VMWare and using Citrix for the management and provisioning purposes. Solution is also ready for compliance customers. MTM Technologies (www.mtm.com) & OVH (www.ovh.com) have built the DaaS solution using VMWare and Citrix technologies. They also rely on public cloud integration including Azure, AWS, Oracle etc. their offers primarily focuses on compliance and high performance desktop requirements. Paperspace (www.paperspace.com) has built their DaaS solution using AWS workspace platform. Where they can support BYOL, Linux, & Container technologies for image creation and data migration. Finally VMware being one of the oldest in VDI technologies have built their DaaS solution offer using their Horizon Cloud (https://www.vmware.com/products/horizon-cloud-virtual-desktops.html) offering. Strength in this platform is that users can access the virtual desktop and virtual applications using multiple protocols including PCoIP & HTML5.

IV. PROFITABLE HYBRID DESKTOP AS A SERVICE

SOLUTION

A. Building DaaS Solution using Microsoft Cloud Technologies

Comparing the vendors details discussed earlier, the fact comes out of the discussions is only 2 major platform for DaaS is available this includes Microsoft and AWS. Citrix adds very important aspect of the management and provisioning capabilities for DaaS deployments. Building a profitable hybrid DaaS solution using Microsoft cloud technologies with all three service models IaaS, PaaS & SaaS with in Public Cloud and Hybrid Cloud deployment models is the focus here.

Microsoft platform with its cloud services are rich and matured enough to build the complete DaaS platform using various cloud services including IaaS, PaaS & SaaS with Azure [61], Azure Stack [62], Office 365 [63], Microsoft 365 [64], Dynamics 365 [65] and Azure Apps [66] with customer’s LOB Applications. Use of Azure Stack with Azure provides the capabilities of building a true hybrid cloud.

Figure 6: Hybrid DaaS Solution Offer

Hybrid reference architectures are listed below does project various added functionalities on the DaaS platform. Various Microsoft cloud services used in 8 different reference architectures can be combined or can be offered as add on services on the basic DaaS Solution offers by service providers.

B. Reference Architectures of Microsoft Hybrid DaaS Solutions

Azure Stack

Subscription #1

Resource group - Local

+Highly Available

Connection Brokers

RD Licensing

Highly Available Gateways

RD Web Access

AD DC

Virtual Network Gateway

LocalNetworkGateway

Azure

Subscription #1

Resource group #1

ER Gateway

Hybrid Environment

SiteInter

connectionResource group Subscription

Azure AD

Session Collection

VM Roles

+

Azure AD Connect

VNET

Hub VNET Spoke VNET

Express Route Circuit

Subnet

Subnet

Secondary DC

High Available RDS Deployment Configuration - High Availability of the RDS deployment is set up by deploying multiple instances of each role (Gateway, Connection Broker, Domain Controller, Fileserver) and configuring them in a farm environment.

Geo-distributed Solution with Azure Traffic Manager - RDS traffic is geo-distributed to datacenters using the Azure Traffic Manager Service. A profile uses routing methods, prioritized list of endpoints to control the distribution of traffic to the cloud services or website endpoints.

Azure Stack

Subscription #1

Resource group - Local

+Connection

Broker

RD Licensing

RD Gateway

RD Web Access

AD DC

Virtual Network Gateway

LocalNetworkGateway

Azure

Subscription #1

Resource group #1

ER Gateway

Hybrid Environment

SiteInter

connectionResource group Subscription

Azure AD

Session Collection

VM Roles

+

Azure AD Connect

VNET

Hub VNET Spoke VNET

Express Route Circuit

Subnet

Subnet

Dynamic Scaling with non-HA RDS Deployment Configuration - with a non-High Availability configuration of DaaS

Azure Stack Integrated System

Subscription #1

Resource group - Local

Virtual Network Gateway

Azure

Subscription #1

Resource group #1

ER Gateway

Hybrid Environment

Site Session Collection

Inter connection

Resource group

Subscription

Azure Backup Vault

Azure Backup Service

Hub VNET

VNET

Subnet

RD Web Access RD Gateway

+

RD Licensing

Connection Broker

+

AD DCAzure AD Connect Azure AD

Spoke VNET

Express Route Circuit

Local Network Gateway

Subnet VM Roles

Hybrid DaaS - Business Continuity with Azure Backup - User Profile disks on the File Server are backed up to Azure using Azure Backup service.

Hybrid Environment

Azure

Subscription #2 Subscription #2

Resource group - Local

Virtual Network Gateway

LocalNetworkGateway

VNET

Resource group #1

Express Route Circuit

Hub VNET

ER Gateway

Subnet

+RD Web Access RD Gateway

AD DC

+

Azure AD Connect

Configuration Server

Azure AD

AD DC

Replication

Site Subscription Resource group Inter connection

SubnetSession

CollectionVM Roles

Connection Broker

RD Licensing

Azure Site Recovery

Subnet

+RD Web Access RD Gateway

+RD Licensing Connection

Broker

Spoke VNET

Business Continuity with Azure Site Recovery (ASR) - Azure Stack Remote Desktop Services (RDS) Virtual Machines (VMs) are replicated to Azure. In the event of a disaster causing the Azure Stack functionality to be unavailable, the RDS VM services replicated in Azure can be used by taking advantage of Azure Site Recovery services.

Azure Stack

Subscription #1

Resource group - Local

+Connection

BrokerRD Licensing

RD GatewayRD Web Access

AD DC

Virtual Network Gateway

LocalNetworkGateway

Azure

Subscription #1

Resource group #1

ER Gateway

Hybrid Environment

SiteInter

connectionResource group Subscription

Azure AD

Session Collection

VM Roles

+

Azure AD Connect

VNET

Hub VNETSpoke VNET

Express Route Circuit

Subnet

Subnet

O365 Apps O365 Apps

Modern Workplace with Office 365 – This provides the availability of productive suite of applications for the consumers.

Azure Stack

Subscription #1

Resource group - Local

+Connection

BrokerRD Licensing

RD GatewayRD Web Access

AD DC

Virtual Network Gateway

LocalNetworkGateway

Azure

Subscription #1

Resource group #1

ER Gateway

SiteInter

connectionResource group Subscription

Azure AD with MFA

Session Collection

VM Roles

+

Azure AD Connect

VNET

Hub VNETSpoke VNET

Express Route Circuit

Subnet

Subnet

Hybrid Environment

AD DC

Secure Identity + Access Control - Using the Network Policy Server (NPS) extension for Microsoft Azure, organizations can enhance security and provide a high level of compliance.

Solution Monitoring with Operations Management Suite (OMS) - Enabling solution monitoring. OMS will be enabled on both Azure and Azure Stack virtual machines with a single OMS Repository/Workspace.

Table 7: Reference Architectures

C. Costing the Microsoft Hybrid DaaS Solution

Service Providers can build a rich cloud based DaaS solution offers using MS Cloud services. I have built a very simple TCO calculator for DaaS Solution in Excel sheet. This DaaS TCO calculator provides the SPs the capabilities not only building and

costing one deployment but, SPs can build and cost their business model for the entire year using DaaS solution offer. TCO Calculator has 8 sections, as shown the screen shot below in Figure 7. Each section provides the ability to calculate the added cloud services in the MS-DaaS Solution.

Figure 7: Microsoft DaaS TCO Calculator

MS-DaaS TCO Calculator is designed to add required cloud services as needed basis, calculating service level costing for the customer with the users in the deployment. Following Table 8 describes the breakdown of the costing calculation. In the following example we will be assuming to build a MS-DaaS solution for an organization with 100 users. 80 users will be using the mobile devices to access the virtual desktop and virtual applications. other 20 will be office workforce using the desktop in the office.

In this example we are calculating for one customer with 100 users. SPs need to pay a special discounted price for Remote Desktop Services (RDS) license under sa special program for SPs. Aka. Service Providers Licensing Agreement (SPLA) [67]. Cost of each license as of today is $6.00, as shown in the calculator.

Section 3 provides the opportunity to design the solution in HA configuration. Business Continuity using ASR & Azure Backup is also configured for this customer. TCO Calculator automatically calculates the monthly price for the customer environment based on the cloud services selected.

SP will have to provide customer the solution with a compliant Identity and security cloud services. SP added Azure Active Directory service with Azure Multi Factor Authentication services on the MS-DaaS Solution.

SP needs to provide the solution to meet the on-prem (20) and mobile users (80) compliance policies. Office 365 (O365) cloud services is provided to the on-prem desktop users, and Microsoft 365 (M365) cloud services is provided the mobile workforce users. M365 cloud services components provides device management services, enabling to manage the remote mobile devices with the capabilities of BYOD scenarios.

Customer doesn’t require the business applications (ERP & CRM) in this environment, I will be not using the Dynamics 365 (D365) costing section.

Table 8: TCO Calculations

MS-DaaS TCO calculator helps SPs in calculating the monthly cost, annual run rate of the customer or the entire managed services business. SPs have the visibility of the Total azure consumption under the Microsoft CSP licensing [68] and SPLA licensing shown in Figure 8.

Figure 8: TCO Calculations with DaaS ROI for SP

V. DISCUSSION ON DAAS

This paper focuses on three aspects of building the cloud based DaaS Solution.

1). Adopting the cutting edge cloud based technologies for sellers

and consumers

Cloud vendor brings a successful complete solution for the end consumer. There is always some gaps left in building a complete solution for the end consumer, if the solution is build using only one cloud vendor based technologies & services. A rich ecosystem of the cloud technologies with presence of cloud vendors, service providers, 3rd party products vendor, makes the cloud solution building a successful venture for all. Releasing new cloud services cannot be more successful unless these services are consumed with other existing services in a customized manner to build a productive innovative solution by the service providers. Building the solutions using multiple service and deployment models is the need of today’s successful solution offering. Business organizations interested in adopting the cloud for various reasons including being more productive with least CAPEX & OPEX, adopting the new solution by making their IT infrastructure future proof, transforming their business to complete digitalization, running their business with meeting al the required regulatory compliance requirements, growing their business without the geographical restrictions, expecting 99.9+% uptime for without facing longer downtime, ease of using the services on the PAYG model, accessing the line of business applications in difficult remote locations over slow internet links, accessing higher resource demanding heavy applications using very low profiles hand held mobile devices etc. With the discussions in this paper it has clearly demonstrated that meeting all these business and technical requirements of the seller as a Service Providers, and the consumer as the SMB organizations; is only possible by adopting the approach of building the managed solutions using various cloud services from one or multi cloud vendors.

2). As a seller SPs building a strong profitable business model using

cloud based DaaS solutions

Building the solution within a competitive price tier including the required functionalities as the base offerings, and leaving the options for add-on features; is a race in the market. Service Providers have mastered this model as a best practice for not only surviving but also accelerating in their space. Paper has demonstrated how SPs need to be creative continually in innovating the new IPs to offer along with their DaaS solution. SPs will need to use the right type of cloud services in a right combination for serving the appropriate requirements of the consumer organization. Various studies and reports also clearly projected that DaaS solution shall not be considered as an economical cheaper option for the replacement of the traditional VDI solution. SPs can leverage the business opportunities in a broader range using DaaS solution as compared to the VDI offer. SPs do not have to invest very heavily and undergo a cumbersome process of meeting the regulatory compliance requirements for hosting the managed DaaS solution for a compliant customer. SPs has to pay very careful attentions in drafting their SLAs for their solution offerings, to make their solution most profitable and more consumable by the end customer organization. It

is an art of playing the balance approach of making profit and staying in the higher demand of the consumers. In order to make a successful profitable solution offer, SP needs to learn a balanced approach of using the strength of existing various DaaS and cloud vendors in the market. Interesting reports have discussed in the paper to show the exploding growth opportunities in cloud business for MSPs. SPs can use the technology improvements like dynamic scaling, multitenancy and compliance to not only boost their profitability but winning more customer confidence by sharing some of their additional profit part with the customers. The fact is that Microsoft cloud technologies are matured enough to build the cloud based DaaS solution using several cloud services, to serve the complete customer organization needs. Adding more SKUs of additional cloud services on the DaaS solution will increase the demand of the solution among the consumers and profitability of the SPs. Proposed TCO & ROI calculator in the paper have demonstrated the capabilities of calculating the solution cost with various technologies; not only limited to one customer, but can be used to calculate the entire SP’s DaaS business ROI.

3). Getting the complete business and technical requirements met by

using the cloud based technologies

DaaS solution consumer seeks the complete functionality of the traditional desktop in the virtual desktop extended with on-prem and mobile access from the remote places using mobile devices. The expectations are to get the same functionalities of desktop using either methods. Business organizations running their business around the clock, seek the virtual desktops and virtual application accessibility in various time zones, across the geographical areas. As an IT work force of the business organizations, does not feel comfortable adopting the 100% cloud model, as they tend to see LEDs on the hardware blinking on-premises. At the same time in order to get the full functionalities, where all the newer applications are aligned to the cloud model form their vendors; hey have no choice left other than stepping into the cloud technologies. Adoptability to the cloud sometime is by choice or some time without any choice. Earlier discussions in this paper brings the interesting facts on consumer adoption for DaaS solutions. Several required attributes with common enhancements are discussed in a depth from the consumer perspectives. The interesting adoptability to the cloud for consumers also clearly aligns with the DaaS solution offers with additional SKUs. Primarily SMB is the type of business organization well suited for DaaS solution. Now with the enhancements in the cloud technologies and with the SPs credibility to bolt these enhancements in the DaaS solution with choice and flexibility of PAYG model approach, making the end consumer more attractive for usage. SMB consumers want to focus on their business nitch. DaaS solution availability with the functionalities to meet their customized requirements helping them focus more on their nitch products and not worrying about running another IT shop with in their business. The enhanced DaaS solution with all the discussed additional features does help the end consumer in consuming more customized cloud solutions provided by SPs.

VI. CONCLUSION AND FUTURE WORKS

Conclusion of this paper is focused around three different aspects of building the cloud based DaaS solution. Aligning the future work around these aspects does emphasize the need of a true multitenant model for the DaaS solution. As of now, no cloud service vendor or service provider has the capabilities of building a true multitenant DaaS solution. This is the limitation of the underlying technology used in building the DaaS solution. In the example of VMWare, CITRIX, Microsoft primarily two protocols are used: Remote Desktop Protocol (RDP) for Microsoft [69] based solution and VMWare has their own proprietary protocol, Horizon [70]. There are lot of investment on these protocols with improved functionalities and new capabilities. At the same time it is lacking the true multitenancy integration with the directory approach for authentication & authorization on the infrastructure. Several SPs have been running the DaaS practices with workaround of assigning a specific organization unit (OU) of the directory to one customer. Implementing a security policies for the customer to be specifically

for this OU, is the common practice of supporting multi tenancy on the shared DaaS environment, offered by the MSPs. This is not a true isolated DaaS environment for the customer. All customers on this environment do share the same directory for the authorization and authentication. This elevates the risk of losing the privacy and security between the customers objects. It is highly required to have the true multi-tenant model for building the DaaS solution.

Cloud services are available on monthly subscription basis. Model of chargeback at the minimum is monthly subscription, no hourly or daily billing capabilities exist directly from the Cloud Vendors on some cloud services. SPs building the DaaS solution using these services limits the price modeling of the solution on per user per month basis. It has definitely is looked at as more of the limitations and considered more in future work.

This paper considered these two burning needs of multitenancy and

minimum hourly billing capabilities as future work. As soon as Cloud

vendors release the new improved capabilities around these two asks,

I will recommend of revising this paper as a future work.

REFERENCES

[1] D. Adams, "Desktop as a Service vs. VDI – What’s the Difference?," 2014. [Online]. Available: https://patriot-

tech.com/blog/2015/01/28/desktop-service-vs-vdi-whats-difference/.

[2] A. Regalado, "Who Coined 'Cloud Computing'?," 31 October 2011. [Online]. Available:

https://www.technologyreview.com/s/425970/who-coined-cloud-computing/.

[3] P. Mell and T. Grance, "The NIST Definition of Cloud Computing," September 2011. [Online]. Available:

https://csrc.nist.gov/publications/detail/sp/800-145/final.

[4] N. Jain and S. Choudhary, "Overview of virtualization in cloud computing," in Symposium on Colossal Data

Analysis and Networking (CDAN), 2016.

[5] B. Arinze and M. Anandarajan, "Adapting cloud computing service models to subscriber requirements," in 16th

International Symposium on Wireless Personal Multimedia Communications (WPMC), 2013.

[6] R. Shattuck, "Seven Reasons Mid-Size Service Firms Should Adopt Managed Services," Forbes, 2018. [Online].

Available: https://www.forbes.com/sites/forbesagencycouncil/2018/01/30/seven-reasons-mid-size-service-firms-

should-adopt-managed-services/#1091869c6a83.

[7] A. M. Talib and R. Abdullah, "A Model of Information Technology as a Service (ITaaS) in Cloud Computing: A Case of Collaborative Knowledge Management System," in International Conference on Advanced Computer

Science Applications and Technologies (ACSAT), 2012.

[8] J. Yao, "On-Demand Optimal Cloud Service Provisioning Composition across Multi-cloud," in International

Conference on Computational and Information Sciences, 2013.

[9] K. Mike, "Complexity Will Drive Demand For Managed Services Providers," [Online]. Available:

https://www.forbes.com/sites/mikekavis/2014/07/17/complexity-will-drive-demand-for-managed-services-

providers/#4612b3934efa. [Accessed 2014].

[10] Y. Duan, Y. Cao and X. Sun, "Various “aaS” of everything as a service," in IEEE/ACIS 16th International

Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing

(SNPD), 2015.

[11] S. Dernbecher, "Having the Mind in the Cloud: Organizational Mindfulness and the Successful Use of Desktop as a Service," in 47th Hawaii International Conference on System Sciences , 2014.

[12] E. Casalicchio, S. Iannucci and L. Silvestri, "Cloud Desktop Workload: A Characterization Study," in IEEE

International Conference on Cloud Engineering, 2015.

[13] A. Srivastava, "vDaaS: Reference architecture," in Annual IEEE India Conference, 2012.

[14] P. H. Nakhai and N. B. Anuar, "Performance evaluation of virtual desktop operating systems in virtual desktop

infrastructure," in IEEE Conference on Application, Information and Network Security (AINS), 2017.

[15] T. Song, J. Wang, J. Wu, R. Ma, A. Liang, T. Gu and Z. Qi, "FastDesk: A remote desktop virtualization system

for multi-tenant," Future Generation Computer Systems, vol. 81, pp. 478-491, 2018.

[16] S. Kibe, T. Koyama and M. Uehara, "The Evaluations of Desktop as a Service in an Educational Cloud," in 15th

International Conference on Network-Based Information Systems, 2015.

[17] A. Celesti, D. Mulfari, M. Fazio, M. Villari and A. Puliafito, "Improving desktop as a Service in OpenStack," in

IEEE Symposium on Computers and Communication (ISCC), 2016.

[18] N. Hill, M. Silver, F. Troni and D. Groombridge, "Market Guide for Desktop as a Service," Gartner, 2018.

[19] dinCloud, "Hosted Workspaces," [Online]. Available: https://www.dincloud.com/hosted-workspaces.

[20] IronOrbit, "Desktop-as-a-Service," [Online]. Available: https://www.ironorbit.com/desktop_as_a_service-

daas.html.

[21] A. C. Hosting, "Hosted Virtual Desktop," [Online]. Available: https://www.acecloudhosting.com/hosted-virtual-

desktop/.

[22] Dizzion, "DIZZION DESKTOP AS A SERVICE (DAAS)," [Online]. Available:

https://www.dizzion.com/dizzion-desktop-as-a-service-

daas/?gclid=CjwKCAjw2MTbBRASEiwAdYIpsSjhH4zwJpXKdGRdkKu7kcDJH-

cMf9ZjIYeBjMNrH6CDZCEx7ranVhoCrloQAvD_BwE.

[23] iNSYNQ, "HOSTING FOR YOUR BUSINESS," [Online]. Available: https://www.insynq.com/.

[24] C. Realtime, "THE BENEFITS OF DAAS," [Online]. Available: https://www.cloudninerealtime.com/benefits-

daas/.

[25] Epic, "Commuity Connect," [Online]. Available: https://www.epic.com/software#CommunityConnect.

[26] R. Networks, "The freedom and flexibility to work from anywhere," [Online]. Available:

https://www.rightnetworks.com/.

[27] sage, "Sage Business Cloud," [Online]. Available: https://www.sage.com/en-us/.

[28] AppDirect, "Solutions for Independent Software Vendors," [Online]. Available:

https://www.appdirect.com/solutions/isv.

[29] CItrix, "Citrix," 2019. [Online]. Available: https://www.citrix.com/.

[30] VMware, "VMware Virtualization," 2019. [Online]. Available: https://www.vmware.com/products/desktop-

virtualization.html.

[31] Chromotif, "Chromotif," 2019. [Online]. Available: https://www.chromotif.com/.

[32] CloudJumper, "CloudJumper," 2019. [Online]. Available: https://cloudjumper.com/.

[33] Liquit, "Liquit," 2019. [Online]. Available: https://www.liquit.com/), .

[34] E. Software, "Ericom," 2019. [Online]. Available: https://www.ericom.com/.

[35] Itopia, "Itopia," 2019. [Online]. Available: https://www.itopia.com/.

[36] Listeq, "Listeq," 2019. [Online]. Available: https://www.listeq.com/.

[37] Nerdio, "Nerdio," 2019. [Online]. Available: https://getnerdio.com/.

[38] Parallels, "Parallels," 2019. [Online]. Available: https://www.parallels.com/.

[39] TetherView, "TetherView," 2019. [Online]. Available: https://www.tetherview.com/.

[40] Tocario, "Tocario," 2019. [Online]. Available: https://www.tocario.com/.

[41] Amazon, "Workspaces," 2019. [Online]. Available: https://aws.amazon.com/workspaces/.

[42] Fr.Me, "Fr.me," 2019. [Online]. Available: https://fra.me/.

[43] A. Srivastava and A. Deshmukh, "Integrate ISV Applications with SaaS Offerings on Cloud," in IEEE

International Conference on Cloud Computing in Emerging Markets (CCEM), 2012.

[44] M. K. Naseer, S. Jabbar and I. Zafar, "A novel trust model for selection of Cloud Service Provider," in World

Symposium on Computer Applications & Research (WSCAR), 2014.

[45] J. Mitchell, S. Rizvi and J. Ryoo, "A Fuzzy-Logic Approach for Evaluating a Cloud Service Provider," in 1st

International Conference on Software Security and Assurance (ICSSA), 2015.

[46] M. Whaiduzzaman and A. Gani, "Measuring security for cloud service provider: A Third Party approach," in International Conference on Electrical Information and Communication Technology (EICT), 2014.

[47] F. C. -. USA, "Credit Scores," [Online]. Available: https://www.consumer.ftc.gov/articles/0152-credit-scores.

[48] A. Pandey, L. Vu, V. Puthiyaveettil, H. Sivaraman, U. Kurkure and A. Bappanadu, "An Automation Framework

for Benchmarking and Optimizing Performance of Remote Desktops in the Cloud," in International Conference

on High Performance Computing & Simulation (HPCS), 2017.

[49] CITRIX, "Desktops-as-a-Service (DaaS) and Hosted Desktop solutions," 2018. [Online]. Available:

https://www.citrix.com/products/xenapp-xendesktop/desktops-as-a-service.html.

[50] U. D. o. H. &. H. Services, "Summary of the HIPAA Security Rule," 2018. [Online]. Available:

https://www.hhs.gov/hipaa/for-professionals/security/laws-regulations/index.html.

[51] P. S. S. Council, "Securing the Future of Payments Together," 2018. [Online]. Available:

https://www.pcisecuritystandards.org/.

[52] FedRAMP, "FedRAMP," [Online]. Available: https://www.fedramp.gov/.

[53] CISCO, "Desktop as a Service (Cloud-Based)," 2018. [Online]. Available:

https://www.cisco.com/c/en/us/solutions/data-center-virtualization/desktop-as-a-service-

solution/index.html#~tab-citrix.

[54] G. Hocking, "Common Goal Partnering: An Exciting New Model For Cloud Service Providers," 2014. [Online].

Available: https://www.forbes.com/sites/netapp/2014/02/11/cgp-cloud/#49620362fe39.

[55] IDC, "IDC Corporate," 2018. [Online]. Available: https://www.idc.com/.

[56] Microsoft and IDC, "Modern Microsoft Partner eBook Series – Download All 5 Parts Now!," 2017. [Online].

Available: https://blogs.technet.microsoft.com/uspartner_ts2team/2016/09/28/modern-microsoft-partner-ebook-

series-download-all-5-parts-now/.

[57] IDC and Microsoft, "The Booming Cloud Opportunity," 2016. [Online]. Available:

https://partner.microsoft.com/en-us/solutions/cloud-partner-profitability.

[58] 4. Research, "Market Monitor: Cloud Computing - Worldwide managed services, 2014-2018," 2015.

[59] N. Kroeger, "Faster, Streamlined Azure and OpenStack Provisioning," 2018. [Online]. Available:

https://dzone.com/articles/faster-streamlined-azure-and-openstack-provisionin.

[60] Amazon, "Amazon Workspaces," 2018. [Online]. Available: https://aws.amazon.com/workspaces/.

[61] Microsoft, "Microsoft Azure," 2018. [Online]. Available: https://azure.microsoft.com/en-us/.

[62] Microsoft, "Microsoft Aure Stack," 2018. [Online]. Available: https://azure.microsoft.com/en-us/overview/azure-

stack/.

[63] Microsoft, "Office 365," 2018. [Online]. Available: https://products.office.com/en-us/home.

[64] Microsoft, "Microsoft 365," 2018. [Online]. Available: https://www.microsoft.com/en-us/microsoft-

365/default.aspx.

[65] Microsoft, "Dynamics 365," 2018. [Online]. Available: https://dynamics.microsoft.com/en-

us/?&OCID=AID720979_SEM_fZygBLkj&lnkd=Bing_D365_Brand.

[66] Microsoft, "Azure App Service," 2018. [Online]. Available: https://azure.microsoft.com/en-us/services/app-

service/.

[67] Microsoft, "SPLA - Licensing Option for Service Providers," 2018. [Online]. Available:

https://www.microsoft.com/en-us/Licensing/licensing-programs/spla-program.aspx.

[68] Microsoft, "Cloud Solution Provider," 2018. [Online]. Available: https://partner.microsoft.com/en-us/cloud-

solution-provider.

[69] Microsoft, "Reote Desktop Protocol," 2018. [Online]. Available: https://docs.microsoft.com/en-

us/windows/desktop/TermServ/remote-desktop-protocol.

[70] VMware, "Horizon 7," 2018. [Online]. Available: https://www.vmware.com/products/horizon.html.

[71] B. D. A. A. S. (. Providers, "Business.com," 2018. [Online]. Available:

https://www.business.com/categories/best-desktop-as-a-service/.

[72] B. Vigliarolo, "VDI vs. DaaS: What is the difference, and which is best for your business' virtualization needs?,"

2016. [Online]. Available: https://www.techrepublic.com/article/vdi-vs-daas-what-is-the-difference-and-which-

is-best-for-your-business-virtualization-needs/.

[73] HPE, "HPE Moonshot for Digital Workspace," 2018. [Online]. Available:

https://www.hpe.com/us/en/servers/moonshot-mobile-workspace.html#.

[74] CITRIX, "Introducing Citrix Workspace app," 2018. [Online]. Available: https://www.citrix.com/.

[75] Microsoft, "Simplify desktop and application virtualization," 2018. [Online]. Available:

https://www.microsoft.com/en-us/cloud-platform/desktop-virtualization.

[76] VMWare, "Horizon Desktop-as-a-Service Platform for Service Providers," 2018. [Online]. Available:

https://www.vmware.com/products/daas-vspp.html.

[77] Microsoft, "Remote Desktop Services (RDS)," 2018. [Online]. Available: https://www.microsoft.com/en-

us/cloud-platform/desktop-virtualization.