Tag Archives: hosted desktops

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meshIP Launches Two New Services!

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meshIP, LLC is please to announce the launch of two new services! meshIP was formed five years ago and has specialized in company formation, business plan development, funding and growth strategies. We are adding to our capabilities to assist small and mid-sized firms in their growth by offering hosted computing and telecommunications services. These offerings allow our clients to get out of the IT business and focus on their business.

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Securing The Virtual Desktop

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Securing the endpoint has always been a headache for IT administrators. The less managed those endpoints are, the worse the headache is. In a virtualised desktop environment, where those operating systems and applications are more managed, does the problem go away?

Ostensibly, security is less of a problem in a virtual desktop environment. In a VDI or Remote Desktop Services implementation, the entire operating system and applications run centrally, and the user’s data remains in the data centre. Nevertheless, there are risks.

One quick-witted Reg reader pointed out that it would be relatively easy for an attack to spoof a thin client using a terminal emulator, for example, and then copy the streaming data to a local drive.

“There will always be risks,” argues David Cowan, of IT services firm Plan-Net. But he adds that there are things you can do to mitigate those risks. “That would be two factor authentication, or a remote access procedure where they have to go to a main portal be part of the network.”

Running all sessions through an encrypted connection broker can also help to secure user sessions from prying eyes. The connection broker can operate in a DMZ, shunting user sessions into a trusted part of the infrastructure as encrypted streams.

Various other attacks are possible on a virtualised desktop infrastructure. A hacker could gain access to an administrative account on a virtual machine, and use that platform to mount an attack on the hypervisor. It may also be possible to mount an attack using vulnerabilities in the virtualisation management software itself.

On the upside, the centralisation of the desktop makes it more manageable, which means that the well-prepared IT administrator will be able to lock down security more effectively. One of the first things that an administrator should do is to create a minimum security baseline.

Gold standard

This baseline should mandate a non-administrative access account for users, limiting the operating system’s exposure to attack. This minimum security baseline will generally form part of a ‘gold image’, that is then cloned for many users.

Other things to consider when creating this gold image include network access control agents for persistent desktops that maintain their state even when the user is logged off. This enables each virtual desktop to check in with a policy server on login, and ensures that it is updated with the latest patches.

It is also possible to rationalise anti-malware packages when using a gold image. Instead of installing all the available features and components of an anti-malware package, including a personal firewall and content scanner, virtual desktop administrators may choose to simplify the installation (and reduce the computational load) by running a single content scanner and firewall at the gateway.

This relies on the fact that all the desktops are contained in the data centre, with a perimeter which should be easier to manage. But each virtual machine will still need an anti-malware scanner. On a conventional stand-alone desktop, a virus scan uses only local resources, which eliminates the load on the server. But when that desktop is hosted on the server, a virus scan can significantly tax resources.

How can systems administrators mitigate this problem? Randomised on-demand scanning is one approach. On-demand scanning sweeps the whole virtual machine for malware in one shot, and can take a significant amount of time, but it can be carried out more easily in a server environment.

Non-persistent desktop image

Standalone machines on the network might be turned off at night, calling for Wake-On Lan functionality to start them up again for scanning purposes. In a server implementation, scans can be staggered throughout the night, and perhaps during the day if a desktop is not being used, to smooth out demand on server resources. Some products also offer offline scanning capabilities, where images can be scanned even when they’re not running.

The alternative is to dispense with on-demand scanning altogether by using a non-persistent desktop image. This type of virtualised desktop is destroyed when the user logs off and reborn, Phoenix-like, when the user logs on again, giving them a fresh image each time. It is then populated with user data and applications. On-access malware scanning can then run in the background, checking user files and emails for incoming viruses.

One of the upsides to this approach is that administrators can personalise a user’s desktop with custom sets of applications while keeping the underying operating system secure. This mix of personalisation and security has been difficult to achieve with conventional stand-alone thick clients in the past.

Security isn’t a foregone conclusion in a virtual desktop system, but it can be far easier to secure user sessions in these environments with correct planning. As with all desktop virtualisation projects, a little forethought goes a long way

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How VDI Can Change The Desktop Management Game

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VDI can simplify the tasks that make desktop administrators hate their lives — the one-by-one operating system upgrades, Windows patch management, client hardware failures and end-user mishaps. But virtual desktops won’t solve any problems without proper planning and infrastructure.

In fact, many virtual desktop infrastructure (VDI) proofs of concept fail because of infrastructure, said Tom Scanlon, CIO of the Massachusetts College of Pharmacy and Health Sciences (MCPHS).

When MCPHS explored a move from physical desktops to VMware View virtual desktops last year, Scanlon quickly learned that the college’s infrastructure needed serious upgrades to handle the higher bandwidth, storage area network (SAN) and CPU power requirements.

“I thought we could support 24 desktops with our existing infrastructure during a pilot, and I almost pulled the plug because the response time was awful,” Scanlon said. “But that wasn’t the software’s fault; it was our hardware.

“Once we went through and refreshed the hardware, it was like night and day,” he added. “You have to have the right equipment, [or] you won’t get a good interpretation of how [virtual desktops] will work for you.”

The case for VDI

Despite the added infrastructure investments, VDI still made sense for MCPHS because the school had to simplify desktop management for the 19 IT pros who support 4,000 students plus faculty and staff at its three campuses. Plus, the college’s computer labs are on an accelerated refresh cycle of new PCs every two years. That cycle is expensive not only in terms of hardware, but also in IT support, Scanlon said.

MCPHS hired Salem, N.H.-based integrator Mosaic Technology to redesign its infrastructure. It did a SAN refresh with Dell EqualLogic iSCSI storage and updated IBM BladeCenter servers with six-core processors and maxed-out RAM, Scanlon said.

So far, the school has replaced about 700 desktops at computer labs in Boston, Worcester, Mass., and Manchester, N.H., with thin clients and VMware View 4.5 desktops using PC over IP (PCoIP). Scanlon said now that the virtual desktops are properly provisioned, the performance level is about the same as a regular PC, and it’s consistent.

“I haven’t had any complaints from the students, and believe me, if they weren’t happy, they’d be outside my office with pitchforks,” Scanlon said.

Scanlon chose View because MCPHS is already a VMware shop using ESX to virtualize servers. The lack of profile management in VMware View didn’t matter, because the college’s virtual desktops are all generic. A new desktop image is provided each time a new user logs in, and MCPHS uses Google Apps instead of locally managed Microsoft Office software to reduce storage requirements, he said.

The downside for end users is video performance, particularly over the wide area network (WAN), because View 4.5 doesn’t support PCoIP over the WAN. But PCoIP is supported over the WAN in View 4.6, which the college will upgrade to over the coming months.

The big benefit to students is that they don’t have to go to the college computer lab to run college-owned apps. “Now they can access all programs and applications from their own devices, from anywhere,” Scanlon said. “No one has to wait for a computer terminal anymore.”

Dustin Fennell, CIO of Scottsdale Community College in Arizona, moved to virtual desktops in 2008 for similar benefits. “Our primary reason was that the traditional black-box replacement cycle is expensive, inefficient and not sustainable when budgets are declining,” he said.

The college, which supports about 12,000 students per semester and more than 800 employees, uses Citrix XenDesktop and XenApp to deliver applications and data to remote students and faculty. Scottsdale Community also created a Web portal for end users to access college applications, including AutoCAD and Adobe Creative Suite 5, that are delivered from either XenDesktop 5 or XenApp, depending on the app.

“We moved to VDI because we want to get out of the business of managing desktops,” Fennell said. “Now we provide stateless personal desktops that follow users. And our apps actually perform better than they do on a brand-new computer, because we aren’t installing apps on the system, slowing it down.”

VDI also makes operating system upgrades much faster, MCPHS’s Scanlon said. In the past, his IT department used Symantec Ghost software to do Windows upgrades one by one. Now they can use that imaging tool with View to roll out multiple Windows 7 desktop images in minutes.

And when end users mess up their systems, IT can roll out a new desktop without having to touch the users’ machines. “Before, if someone had an application issue, we would have to take everything offline,” Scanlon said. “Now we can just update the image and tell the virtual desktop to rebuild, and the problem is fixed in a matter of hours.”

He said Scottsdale Community College is taking things a step further and moving toward an environment where there are no OSes on any client machines, and everything is virtual, Fennell said.

For a while, the college ran in hybrid mode, with some apps delivered from the Citrix environment and some apps running locally. Now, there are no locally installed apps, other than Microsoft Office on Windows. “Eventually, there will be nothing on the endpoint device,” he said.

VDI: An investment in efficiency

Moving to virtual desktops won’t reduce MCPHS’s IT costs for at least a few years because of startup expenses including licensing and infrastructure, but the college expects to see a return on its VDI investment within five years. For example, Scanlon said he spent about $300 per thin client, which is expected to last more than five years, versus $600 for the laptops that MCPHS bought every two years.

Scottsdale Community College funded its virtual desktop buildout using capital that would have been spent on PC replacements, and though VDI does cost more upfront, the long-term efficiencies are significant, Fennell said.

“Virtualizing your desktop environment may cost more, but if you think outside the box and look at what the end users want and need, between VDI and application virtualization, you can provide better access and better performance,” Fennell said. “We save $250,000 per year at this point, and now the IT department actually funds innovation grants…. It has been a transformational change for us.”

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Where is Desktop Virtualization Today?

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Earlier this year, the Wikibon community held a Peer Incite to discuss the realities of Desktop Virtualization. What we found was that while desktop virtualization is seeing significant growth, it tends to be strongest in certain vertical niches and the ecosystem is highly fragmented. As Michael Keen of Lakeside Software says, one of the biggest challenges is mapping out a customer’s environment and finding the places where Here Be Dragons which can be the downfall of a deployment. The process for creating a desktop virtualization deployment is not a fast or easily repeatable solution and this has contributed to slower adoption generally. The purpose of this article is to discuss the ecosystem and give guidance as to what is needed from the ecosystem to move from today’s niche environments ultimately to a solution which could allow any user to access information from any device, anywhere.

How Desktop Virtualization Differs from Server Virtualization

The initial justification for server virtualization is straightforward – it is about getting higher utilization out of resources by consolidating servers. Desktop virtualization is more complicated. There is a compelling story to simplify the maintenance, backup and security of desktops through centralization, but the overall solution is more complicated going from a desktop (before) to a client/server/management (after). The solution is weighted heavily towards OpEx savings that must offset an expenditure of CapEx. Since there are impacts to storage, compute and network, understanding the true cost of a solution and the organizational impact is difficult to gauge upfront. The solution intersects with other IT trends (especially mobile) that are helping to redefine how workers and technology interact.

Hypervisors and Client Virtualization

While the traditional office worker setup was defined by a Wintel configuration, the desktop virtualization solution, while a lot more complex, starts with a hypervisor and desktop virtualization software. Citrix is the current leader in desktop virtualization with XenDesktop. VMware is the leader in hypervisor sales; while VMware is clear that it will partner with Citrix, it also sells a competitive solution in VMware View. The hypervisor and desktop virtualization solutions have continued to broaden scope.

Desktops, Thin Clients and Mobility

Since the desktop image is now managed at the server, IT organizations can potentially be much more flexible in the devices that are delivered to users. To start with, this means that rather than only choosing new desktop/laptop models every year or two, they can be updated on a more frequent basis. Since cost containment is always a concern, specialized options for the virtual desktop should be considered such as Pano Logic’s Zero Client or other thin client devices. The workforce is become more dispersed and mobile, so the future of this technology is around solutions that go beyond the “desktop”. Users should be able to access their system from a desktop, tablet or mobile device. Cisco looks to pair its strength in Unified Communications with desktop virtualization solutions to create the Cisco Virtualization Experience Infrastructure.

Storage

Like server virtualization, storage is critical for desktop virtualization deployments. Storage is both an important component of VDI architecture and a significant portion of the overall cost of the solution. Every storage vendor has put together architectures, often utilizing SSD/Flash drives, to help deal with the high performance requirements of boot storms. There are also companies like Atlantis Computing and Virsto Software that look to increase performance and cut the cost of storage solutions for desktop virtualization deployments.

* Storage is the number one consideration for non-trivial VDI implementations.
* Many problems tend to be about I/O and storage.
* For every $1 spend on virtual desktop deployment, $3-$10 is spent on storage.
* How much/how fast? i.e. It’s not just about how much storage capacity is needed but increasingly about how fast data needs to be accessed
* Sizing virtual desktop installations (including mobile) is critical for storage
* I/O is random – Generally, individual desktop streams will be randomized in a VDI environment, which means poorly behaved storage with a mix of reads and writes.
* Test at small scale (e.g. one dozen seats doing random access IO) and scale carefully.
* Boot storms are a particularly onerous problem.
* Questions remain related to workload, streaming apps, remote access, graphical load, etc.
* Users should plan on anywhere between 10-30 iops per seat as a rule of thumb.
* The bottom line according to Peglar is it’s not capacity it’s IOPs that are problematic in terms of achieving the goal – which is creating a virtual desktop experience that is equal to or better than a physical desktop.

Networking in the Data Center and WAN

Desktop virtualization adds to the increased demands on the network from server virtualization. The virtualized network requires greater bandwidth between nodes. There are a variety of options to redesign the network including moving from 3-tier architectures to 2-tier architectures that replace Spanning Tree (such as Cisco’s FabricPath) or Juniper’s single-tier QFabric. Most desktop virtualization solutions today are limited to LAN deployments. WAN-based solutions are possible, but have challenges with management, security and the inherent problem with maintaining a connection over distance.

Services

The immaturity and fragmented nature of desktop virtualization solutions leads customers to lean heavily on services. Consultants can help through the entire lifecycle: from planning and design (understanding the proper pieces that should be put together and understanding the user requirements), through implementation and beyond. One of the challenges holding back broader adoption of desktop virtualization is that understanding end-user requirements is a complex, non-repeatable process; Jason Langone has opened a community-based project to help those interested in VDI understand performance profiles of various user types. Education and standardization/streamlining deployments will broaden the addressable market for desktop virtualization.

Ecosystem Maturity

VDI today has been confined to narrow use case where tasks are repeatable and desktop user leverage is somewhat limited. The term VDI (i.e. “Desktop”) is increasingly outdated as the mobile enterprise is taking the world by storm. VDI must evolve to be user-, data- and application-centric and accommodate anywhere, anytime, anyapp access for users. The key to this will be ecosystem maturity.

This starts with the central players, including Microsoft, VMware and Citrix. How these big vendors choose to collaborate with the ecosystem and each other will say much about the future of the desktop. Other efforts such as the VDI coalition or the VDI Alliance, while noble, don’t have enough clout in and of themselves to change the market.

The bottom line is the industry as a whole needs to put forth a VDI vision that is compelling, cost effective and transformational in order for VDI to evolve to the next level.

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Hosted Desktop Strategy Questions

One of the challenges of evaluating cloud computing and the use of hosted desktops in the small business enterprise is understanding not only the business case ROI, but the operational impact. Here are 30 questions to assist you in thinking through the issues associated with deploying hosted desktops.

First some definitions:

VDI, Virtual Desktop infrastructure = Dedicated Virtual Desktop (hosted desktop)

There are two kinds of VDI: server-hosted and client-side. A Server-Hosted Virtual Desktop Infrastructure (VDI) is a dedicated remote desktop solution providing remote access to Windows XP/Vista/Win7 or Linux desktops. The virtual machines are run from within the data center. The virtual infrastructure increases the system’s independence, availability and manageability.

The following questions should be part of the analysis to deploy a hosted desktop strategy:

1. What are the use cases? And does the use-case require Virtualization?

2. What do I want to achieve?, lowering TCO?, business enabler, overall cost of ownership and cost reducer?

3. What is the business case?

4. What’s the user experience using Multimedia, NextGen, Video/Voice, 2D/3D applications? What do users expect from the hosted desktop?

5. What endpoints do we support and facilitate and what is the role of these devices in the end-user experience?

6. Secure Access and Secure networking, how do users, with a variety of endpoints (rich, thin, zero-clients and mobile devices) connect to the hosted desktop?

7. What is the impact of Secure Access and Secure Networking solutions on mobile devices while connecting to the hosted desktop? What is the user experience with these solutions?

8. Do we need to manage the endpoints?

9. How is the hosted desktop managed? OS deployment, application distribution, patch management etc. etc. Is client management mandatory?

10. Do we need image management?

11. How are Windows applications delivered within the hosted desktop? Unattended or manual Installation, Application Virtualization or the applications are part of the (golden) image? What is the strategy?

12. Are User Installed Applications inside the hosted desktop needed?

13. What is the performance and storage impact of Application Virtualization?

14. What is the impact on storage and how does it affect the business-case?

15. Do you need local or centralized storage?

16. Do we focus on stateless (pooled, shared) and/or stateful (assigned, private) images?

17. What is the impact on storage, manageability, security, legal and business-case?

18. What is the impact of client management solutions in a stateless VDI scenario?

19. How do we design, build and maintain the (golden) Image(s)?

20. Windows 7 or Windows XP as core hosted desktop OS platform? x64 or x86?

21. How does the solution scale? What do we need from a scalability point of view?

22. How do we size the hosted desktop and corresponding infrastructure and what are the best-practices for optimizing the hosted desktop?

23. What is the performance and bandwidth impact on the network infrastructure; LAN, WAN, wLAN?

24. How do we design, build and maintain the user’s profile and his workspace?

25. Licensing; Operating System, Client Access Licenses and (Business) Applications?

26. Do we need to backup (and restore) the hosted desktops?

27. Is Anti-Virus needed? Inside the VM or as service module on the Hypervisor? What is the performance impact of AntiVirus?

28. Is the IT organization mature enough to support and maintain the complete technology stack? What is the knowledge and skill-set of the IT-department?

29. Is separation of Operating System, Application and User Preferences inside and outside the hosted desktop part of the overall strategy?

30. Bottom Line: What’s your current desktop strategy?

meshIP can assist you with the strategy and deployment of hosted desktops and other cloud services.

Cloud Computing And The Small Startup

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David Fearon looks at the basic justifications for cloud computing in life at the sharp end of business.

I’ll be covering some of the ins and outs of practical cloud deployments in later posts, but for this first one I wanted to make some points from my latest experiences starting up a small business project.

From those experiences I can tell you it’s entirely possible to run an independent venture on a very small budget, with people on every corner of the globe, at very little cost and with astonishing utility when it comes to everyday communications. In fact with the limited budget we’ve had in our start-up, cloud-based applications and storage have made the impossible not only feasible but incredibly cost-effective to boot.

We’re basing all business-related file storage and communications infrastructure in the cloud. That means cloud-based email and collaboration tools, and not a single exclusively local copy of anything on our respective laptops and desktops. Pretty much the only exception to this is the occasions one of us is working on something they feel reticent about showing to the rest of the team before it’s a fully fleshed-out concept.

Backup is a special exception which I’ll cover in a later post, but the thrust of it is the whole business lives in the cloud, and we all have access to everything that the business as an entity produces. It makes for a workflow with the absolute minimum of interruptions.

It goes without saying that in many quarters this is considered heresy and far from The Way That Things Should Be. But small ventures are about getting things done, and getting them done fast, clean and well. When you have nobody but yourself to blame for failure, the path of best efficiency is often the one that you simply have to take. Trust plays a big part here. The broader point is that, as an IT person, you need to be aware of the risks of everything you do and the best way to do it within the parameters of acceptable practice.

Our start-up is one based primarily on IP (that’s the intellectual-property type of IP, not the internet protocol variety) and exploiting the application of specialist skillsets from a small but diverse team. This defines our modus operandi: extreme flexibility and the ability to get things done without delay come first. We’re dealing with what many small businesses must perforce deal with: the need to squeeze the very last drop of efficiency out of everything.

The point to bear in mind is that we’re not idiotic cavaliers; we’re aware of all risks, insofar as anyone can be aware of everything that could possibly go wrong. If the main thrust of the business were, for instance, manufacturing, retail or anything involving customer data that the law required us to protect, things would be structured differently.

Would I expect this frontiersman approach to be barrelling along unaltered in three years’ time? Absolutely not. If and when the venture in question flourishes, things will become more formalised as the team grows and the company becomes responsible for more than just itself.

The aspect of the business that I would expect to remain unchanged is its fundamental approach to basing all operations in the cloud wherever possible. It’s just insanely cost-efficient in so many areas. I’m increasingly of the viewpoint that when you’re at the sharp end, the old mindset of keeping everything local because of some ingrained sense of propriety is one that will bite you hard unless you have a clear, well-defined need to go that way.

In other words, local compute power and storage should become the exception for your business, not the rule.

If you want to be able to walk into your very own server room, run your hands along the machine racks and get a fuzzy feeling from the ceaseless dance of activity lights blinking in the darkness, please go ahead. If, however, you want to make maximum use of available revenue and resources, you might have to forgo that understandably human pleasure.

Go for a stroll in the sunshine instead, and bask in the reassurance that the racks, their power provision, cooling, disaster recovery and maintenance are someone else’s problem.

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Don’t Forget The Network

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Desktop Virtualization Two cups and a piece of string won’t cut it in a virtual world. If you are virtualising your desktops, your network must be able to cope with the additional traffic load, and resilient enough to support users who require access to their desktops at all times. How can you ensure it measures up?

A poorly configured network can lead to poor response times and service drop-outs. It can also worsen the bootstorm problem, incurred when many users log in at once.

“The whole networking side is something that lots of people forget about until they’ve done the project,” warns Tony Lock, programme director at analyst Freeform Dynamics.

A virtual desktop infrastructure (VDI) configuration in which an entire virtual machine is hosted centrally for each user represents the worst-case scenario for any harried network manager. Nevertheless, says Michael Allen, director of IT service management solutions at Compuware, it offers some predictable parameters. Bandwidth requirements in a VDI implementation are relatively easy to define. Latency is the real issue.

“There are only so many keys that a user can type in a given second, while the keyboard and mouse uses just a tiny bit of bandwidth up to the data centre,” says Allen. “And the only thing coming the other way is screen updates.”

“We work on the basis of 50k of bandwidth per active user,” says Scott Underwood, senior solutions specialist at IT and telecoms consulting firm Niu Solutions. “Really heavy graphics work could send it up.”

While bandwidth may be predictable, latency remains a challenge (and of course, a lack of the former will affect the latter). Users want a responsive machine, which means data must pass over the network fast enough so they don’t have to wait.

“Usually, if you experience latency of over 150ms, you’ll get calls to the helpdesk,” says Mark Edwards, technical director of network consulting firm Capital Networks. To be safe, aiming for a latency of a 0.1 seconds or under is best.

Latency is affected by the physical distance across the network, but that is not the only factor: other traffic travelling over the network to the data centre could force VDI traffic to queue up. Perhaps a remote backup spikes network traffic at a certain time of day, or voice over IP traffic creates problems. Requirements may also be seasonal. A retail network may look fine until that all-important fourth quarter when holiday sales pick up.

This makes proper baselining particularly important, and there may be a need for quality of service protection on the network. On IP networks, technology such as Cisco’s low-latency queuing is an option for guaranteeing bandwidth.

Allen cites one client who complained of terrible performance on the network. On further analysis, he found that an IP security camera was streaming traffic to a proxy server sitting in Switzerland. A simple design flaw was choking the network. The moral is always look for the simplest fix first.

WAN connections can create both latency and bandwidth problems, given the higher cost of throughput. Lock recommends WAN optimisation measures, such as traffic compression to reduce network overhead. “You can do things like putting more of the compressed traffic together into larger packets so that you’re not pushing traditional smaller IP packets up and down the line,” suggests Lock.

What about resiliency? Some Reg readers have worried about the potential service effects of a network dropping out. “In many organisations with one PC per desk, if someone’s machine fails at a critical time – say accounts running the payroll – they can often walk to another PC near to them and carry on working,” said one. “It’s not the same in a virtualised world.”

Edwards argues that many networks are simply not robust enough, especially in smaller businesses. Ideally, the situation calls for two of everything, including dual-honed switches and hot standby redundancy protocols. “You might have a number of access switches in the closet, and each of them would be dual-connected into pairs of distribution switches,” he says. “So, if a switch failed in the access layer, it would affect no more than 24 to 48 clients and there would be spare switches. It’s a cost-benefit decision.”

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Hosted Desktop Strategy Questions

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