nterprise Voice over IP (VoIP) adoption continues to grow exponentially. A 2005 study
by International Data Corp. (IDC) projects business VoIP will hit $7.6 billion by 2008,
a whopping compound annual growth rate of 282%.
Organizations are considering VoIP deployments for a variety of reasons, including improved
feature sets, reduced complexity and the elimination of long distance charges. When it comes
to a VoIP deployment, there are three distinct steps most enterprises follow:
g Needs analysis: Is VoIP right for me?
g Technology analysis:Which solution/vendor meets my needs? g Deployment analysis:How do I make it work?
Once you have determined that VoIP is right for your organization, you must select a
technology and vendor of choice. At that juncture, you have already invested significant time
and resources. Many enterprises mistakenly believe the hard part is over when you select
a VoIP vendor. However, the actual deployment itself is where the rubber really meets the road.
You need to take steps to ensure VoIP will work on your existing network.
VoIP provides a true dichotomous challenge for most organizations because it represents
a major challenge for traditional voice managers who talk in MOUs and POTS with data
managers who think about Mbps and packets. With VoIP, the paradigm shifts for the voice
group by changing standards from number of trunks needed to number of concurrent calls
supported. For data managers, there is a huge difference between an e-mail that takes 30
seconds to transmit as opposed to when a sales manager picks up a phone to call a customer
and there is no dial tone.
A simple scenario will highlight the difference in approach for traditional data applications
and VoIP. For most data applications, packet delivery ratio is paramount – if a packet is not
delivered, there will be gaps in the information received. Many people think delivery ratio is
more important for VoIP – but it really is less important than delay and jitter. The human ear
will “smooth out” the missing voice packets but delay will make the call sound choppy.
This paper will focus on how enterprises can deliver holistic VoIP lifecycle management and bridge
the gap between traditional voice and data approaches when implementing a VoIP solution.
Holistic Lifecycle Management
T
he term holistic lifecycle management sounds like an academic description devel-oped by a group of analysts sitting for days on end in a windowless room. While the term may sound academic, the process is a tested, straightforward approach enter-prises need to follow to successfully roll out and manage VoIP. A holistic approach to VoIP focuses not only looking at VoIP in and of itself but how VoIP affects other applications and users across your infrastructure. Lifecycle management focuses on the evolving nature of your network infrastructure. What happens tomorrow will likely be very different from what happened today.g Assess: Determine network readiness
g Monitor:Discover and isolate performance issues g Manage:Troubleshoot and resolve issues g Validate:Observe performance by call g Report:Baseline and trend
g Control:Improve VoIP performance
As we delve deeper into each of these six steps, you will notice there is some overlap between each one. This is not to be unexpected as there is no clean line of demarcation between each process. Holistic lifecycle management is an ongoing, dynamic process intended to improve the performance of a VoIP deployment while maintaining existing data application integrity. The ongoing nature of lifecycle management assumes the performance of VoIP and all other applications will never be perfect – however, it can be continuously improved over time.
Determine Network Readiness
The first step enterprises should carry out is a complete assessment of network readiness. Deploying a new network infrastructure to carry only VoIP traffic eliminates one of the main benefits of using VoIP, network consolidation. To have a successful VoIP rollout, the voice traffic must coexist peacefully with existing business-critical data traffic. Without a network assessment, your enterprise runs the risk of major performance issues – both with existing applications and with the VoIP rollout. Too often, enterprises assume they have adequate bandwidth and then must firefight major problems during implementation. Or enterprises add more bandwidth at every location assuming additional bandwidth requirements will be consistent network-wide.
There are three ways to complete a network assessment for VoIP: synthetic call transactions, management information base (MIB) polling and granular user data via passive monitoring. The synthetic call approach places simulated calls across the network and characterizes the quality of the calls. While this approach can help quantify parameters before deployment, including simulated Mean Opinion Score (MOS), the synthetic calls do not provide granular analysis of how existing data traffic impacts VoIP availability and quality. In addition, it is actually adding management overhead to your existing critical application traffic.
As a second option, many enterprises conduct an assessment using a reporting tool that polls standard MIB data from routers and equipment. This approach leverages traffic data in
the analysis but typically averages the utilization across five-, ten- or fifteen-minute buckets. The weighted average can easily skew data so a network that cannot adequately handle a VoIP deployment appears to be ready for VoIP calls. This false sense of security can actually be worse than not doing an assessment at all.
The third approach for a network assessment relies on actual user data from across the enterprise to determine VoIP readiness. The key is passive monitoring that provides up-to-the-second granularity. By measuring actual user data, enterprises can determine how many simultaneous VoIP calls at certain quality levels can be handled on the existing net-work without negatively impacting existing data applications. Without granular user data, you are taking an educated guess on the impact of a VoIP deployment. The challenge for many enterprises is how to collect granular performance data without impacting the net-work itself. Detailed and granular user data takes the guessnet-work out of assessing netnet-work readiness, so you now know where additional resources will be required before the deploy-ment begins.
Find and Isolate Performance Issues
For most enterprises, the acceptable end-user experience varies substantially from tradi-tional voice to data applications. Voice managers historically have little or no tolerance for variations in call quality while data managers are most accustomed to data’s traditional best effort philosophy.
Once VoIP is deployed, monitoring detailed actual traffic – both voice and data – is the next step to identify and isolate performance issues. Trouble tickets will flood network managers when poor VoIP quality is noticed. A huge challenge for most enterprises is the perception of VoIP. Studies have shown that users believe quality is much worse for VoIP than tradi-tional PSTNs – even though actual measurements prove this is misconceived. What this means for network managers is that a VoIP deployment will likely increase the number of performance complaints, no matter the actual call quality. This can waste an IT depart-ment’s valuable time trying to track issues that, from their point of view, don’t exist.
Monitoring actual VoIP usage in conjunction with other data traffic helps eliminate the guess-work in performance monitoring. With proactive monitoring, enterprises can determine the true cause of poor VoIP performance – whether it be new applications, network issues or service level parameters. With enhanced visibility, enterprises can also isolate performance issues by sectionalizing the cause of the performance degradation that impacts end-users.
Troubleshoot and Resolve Issues
Following closely behind monitoring – and many times in tandem with that important step – is troubleshooting and resolving problems associated with poor performance. As men-tioned earlier, network managers typically must respond immediately to complaints about no dial tone or unacceptable call quality. There are many potential causes of poor VoIP performance. These range from physical problems on the local loop to an over-utilized port to misconfigured class of service (CoS) settings to high levels of jitter within the voice application itself.
Once the cause of degradation is isolated, troubleshooting the problem can greatly reduce the amount of time to resolve the issue. While a problem is occurring, seconds and minutes saved often go straight to the bottom line.
A bigger challenge than real-time issues for many enterprises are the intermittent issues that come and go. Intermittent issues typically grow and cause more havoc over time. These occur when you least expect it. When it comes to VoIP, it is even more critical to find the pesky intermittent problems and resolve them before they grow and more users are negatively impacted. Network managers must be able to troubleshoot issues ranging from the local loop to the port to service level parameters across each and every site.
Performance by Call
As discussed earlier, one of the biggest challenges for network managers is validating performance by VoIP call. MOS has become a standard for gauging the quality of individual call performance. In order to understand the end-user perspective, network managers must dig deeper than just MOS to validate what impacts the performance of each call.
Too often, many enterprises make a critical mistake in averaging the call performance. For example, the IP PBX may provide statistics on average MOS scores across a site, but an enterprise may be at risk when they feel they exceeded a target MOS score 99% of the time. The key is validating performance to optimize the VoIP performance to improve the other 1% of unacceptable calls.
Holistic lifecycle management intertwines different components to optimize the VoIP applica-tion performance. For example, it is not adequate to just know a call may have a low MOS, it becomes imperative to know the true cause of the poor performance – whether it be jitter, latency, a layer 1 issue or another application fighting for critical resources. Enterprises need up-to-the-minute access to this information to validate performance across each of the potential causes of poor quality.
Baseline and Trend
A wise adage for network managers to follow is that good organizations baseline perform-ance, but great ones continually baseline and manage performance. In today’s world of new applications, remote users, security threats, and mergers and acquisitions, the importance of reporting becomes more critical. What has worked well over the past year may no longer be sufficient when deploying VoIP or other peer-to-peer applications on your infrastructure. With strong reporting capabilities, you can be much more proactive in optimizing your appli-cation and network performance. For example, instead of waiting for a problem to occur – such as over-utilization negatively impacting individual call performance – and then reacting to the situation, trending could identify the growth of utilization over time. Thereby you can add bandwidth where needed before end-users are impacted.
Most enterprises do not remain stagnant when it comes to networking requirements, so a one-time VoIP assessment is soon outdated. You may have a merger, add a remote office or deploy another application. Each and every one of these changes can impact the quality of VoIP performance. That is why trending is so valuable for your organization. What may work fine today for a location may be inadequate in six months. By reporting and trending, you can plan for the new requirements over time instead of firefighting issues after they have occurred.
Improve VoIP Performance
The final step in the lifecycle management approach is to leverage the first five steps in order to proactively control your VoIP application and network to improve overall performance. The control parameter may encompass many different areas depending on where quality may be improved in your organization. Control can include aspects such as:
g Increasing bandwidth to handle additional usage caused by VoIP g Leveraging class of service capabilities with an MPLS-deployment g Improving service level parameters from the service provider
g Shaping traffic so the most business-critical and delay-sensitive applications have priority g Eliminating recreational applications such as file sharing and streaming media
The control parameter requires the holistic approach to performance management. Simply looking at a single application, site or user where a problem may be occurring is not enough. It becomes imperative to not only look at that individual issue, but evaluate how that issue might impact or be impacted by other business-critical applications throughout your infrastructure.
By approaching VoIP implementation and management in a holistic manner, you can ensure you are ready for a VoIP deployment, monitor its progress, proactively manage and trou-bleshoot issues, validate call quality, report on deployment success and control parameters to improve performance. As your network and applications evolve, you will be ready for the new challenges in managing performance across your entire infrastructure.
Holistic Lifecycle Management
with Visual UpTime
Select
T
his paper has focused on how the holistic lifecycle management process can assist with VoIP deployments as well as manage the existing data applications and infra-structure. In order to complete this process, you need the visibility and tools to manage the entire process. Visual UpTime Selectprovides complete visibility from the local loop through individual application flows. Utilizing Visual UpTime Selectallows you to know if you are ready for a VoIP deployment and helps you monitor and manage it once it is rolled out.Determine Network Readiness
Visual UpTime Selectmonitors actual user traffic data with up to one-second granularity. This eliminates the weighted averaging of a polling solution and provides more detailed analysis than synthetic testing. The solution can capture such granularity by utilizing intelli-gent appliances to passively monitor actual traffic flows and store it locally. By monitoring actual traffic flow over a period of time, the solution provides comprehensive assessment readiness data.
With a single-click VoIP assessment report (right), the system interprets the data and provides vital information to determine your existing network’s readiness for a VoIP deployment. The reports include criteria such as:
g Call quality metrics such as jitter, utilization, avail-ability and lowest available capacity
g VoIP call capacity per site
g Network usage trend broken down by application
g Site assessment including congestion, utilization, and utilization by busiest hour of day
g Intermittent issues by site g Site jitter, packet delivery ratio
and round-trip delay
Armed with this information, you can determine if individual locations have sufficient band-width or if locations need additional or less bandband-width as part of the VoIP deployment. Proper site assessments will greatly reduce potential VoIP performance issues throughout the deployment while optimizing your bandwidth resources.
Discover and Isolate Performance Issues
Most organizations strive to be more proactive in application and network management, but in reality, the vast majority are reactive. When it comes to poor VoIP performance, the pain the traditional reactive approach causes will be intensified with unhappy end-users.
Proactive monitoring of application and network performance can reduce or eliminate many potential issues.
With Visual UpTime Select, there are two key components of proactive monitoring: auto-dis-covery of applications and servers and threshold-based alarming. The system continually monitors traffic flows and auto-discovers new applications (below)or servers. These applications can be authorized such as the new VoIP testing deployment or rogue such as peer-to-peer file transfers. By immediately identifying a new application, you can determine the extent that it will impact VoIP performance.
With threshold-alarming, you can be notified when network and application performance exceeds normal baselines. For example, if you are anticipating the SIP rollout for VoIP to take 15 percent of a location’s bandwidth, you can set a threshold to notify you if the usage exceeds a threshold. If the SIP usage takes 35 percent of the bandwidth, you may have a misconfiguration that occurred during the deployment or you may have just underestimated the amount of bandwidth needed for this location. In addition, you can set round-trip
delay thresholds that will generate alarms (above)if delay is greater than anticipated. The ability to isolate potential degradation is important and is something you should resolve before end-users are negatively impacted.
Troubleshoot and Resolve Issues
Even with proactive monitoring and an extremely robust infrastructure, every organization will have problems that require immediate troubleshooting. There are typically two types of problems for VoIP and all other applications: those occurring now and those that are inter-mittent. The issues currently occurring require real-time visibility to isolate and solve the problem. Visual UpTime Selectprovides real-time views across Layers 1-7 to find out what is causing the problem as it occurs. For example, is the local loop bouncing? Is a port overutilized? Or is the round-trip delay too long?
Intermittent problems are usually even more complex and troubling for most organizations because they come and go – and more than likely, they grow over time. With Visual UpTime
Select, you can scroll back in time with the graphical interface to identify problems that hap-pened an hour ago, three days ago or two weeks earlier. For example, you can identify an end-to-end circuit to verify traffic is flowing between locations throughout a two-week period. A huge challenge for most network organizations occurs when the vast majority of trouble tickets deal with application problems – ERP is slow, e-mail is down, CRM doesn’t work – but the network group does not control the applications or the servers. Robust troubleshoot-ing must include visibility into both the network and application components. Visual UpTime
Selectincludes complete Layers 1-7 visibility (below)so you can troubleshoot issues ranging from the local loop to the end-to-end circuit to the individual application flows. For example, you can monitor individual VoIP calls to monitor and troubleshoot potential issues.
Observe Performance by Call
Validating the performance of VoIP calls, and more importantly, the criteria that impacts the call performance, is the next step in VoIP lifecycle management. Frequently, organizations focus too nar-rowly, such as on a single server compo-nent, or too broadly, such as on service provider’s monthly SLA reports. In order to properly validate VoIP performance, objec-tive measurements of performance across the infrastructure are paramount.
Visual UpTime Selectmeasures VoIP per-formance and statistics independent of the
IP PBX vendor or transport providers. For example, many carriers provide reports on service level metrics like delay, availability and throughput. However, they tend to average the results across the entire network and every site over an extended period of time – perhaps as long as a month. With Visual UpTime Select, you receive Visual Service Advisor (above), which provides up-to-the minute measures on these parameters between individual locations, so you are able to validate performance across the infrastructure.
Baseline and Trend
As discussed earlier, application usage and performance will change over time. The importance of baselining and trending is heightened due to the sensitive nature of VoIP deployments. Visual UpTime Selectpassively measures all application usage from every site in your network. Consequently, you have up to a one-second level of granularity (left). With single-click report-ing, you are able to report on topics including VoIP performance, VoIP call capacity, most over-utilized sites, worst service level parameters and breakdown by applications. You can use the monthly trending to determine where additional resources may be needed before end-users are impacted.
More than 90 predefined reports are divided into standard and executive reports. The standard reports drill down into great detail such as which applications are consuming how much band-width on a single end-to-end circuit. These reports are used by network managers to optimize network and application performance. The executive reports focus on enterprise-wide criteria such as most overutilized or underutilized sites across your enterprise. The reports are generally used as high-level status indicators for executive management.
Improve VoIP Performance
The goal of the first five steps of the holistic VoIP life-cycle management process is to supply the information you need to control the performance of your VoIP calls.
Instead of guessing how much bandwidth you might need at each site, Visual Burst Advisor uses one-second granularity to make automatic recommendations where port speeds may need to be increased. Now you will know exactly where you must add bandwidth and how much you should add instead of guessing or adding
the same amount everywhere during the deployment. If you are implementing an MPLS-based network solution, Visual UpTime Selectmonitors and meas-ures up to eight different CoS settings. Now you can quickly identify if VoIP and other applications are set correctly and determine if your usage is exceeding the carrier’s thresholds which may negatively impact performance. In addition, the CoS monitoring pro-vides individual SLA parameters for each individual setting so you can monitor if real-time traffic has better performance metrics than best-effort traffic.
Finally, you can monitor applications by user and determine if unauthorized usage is impacting the performance of critical applications. And if a new server or application appears (above) on your network, Visual UpTime Selectcan automatically notify you of its presence, allowing you to decide if and how you will control this new issue. The key to control is having the right information in a user-friendly format so you can make the best decision for your organization.
Troubleshooting Poor VoIP Performance
Even with a holistic VoIP lifecycle management approach, all enterprises will experience poor VoIP performance at some point. When a problem occurs, a trouble ticket is usually opened with comments like “There is no dial tone” or “The quality is terrible.” Visual UpTime Select
provides the detailed Layers 1-7 visibility to isolate and resolve the issue.
In this real-life scenario, a mid-sized healthcare organization began deploying VoIP
to 15 percent of its remote sites. Almost immediately, an end-user complained of poor VoIP quality. As a network manager, you can drill into the problem using Visual UpTime Select. First, you can go back in time and look at individual applications flows by specific VoIP protocol to verify the end-user was connected. You verify the end-user did have a SIP application flow with another end-user (above).
Next, you can delve into up-to-the-minute SLA parameters (left)to see if round trip delay is impacting performance. We can see the delay hasn’t increased.
By moving to the troubleshooting toolset, you can look at the individual port to verify usage. In this scenario, the port usage was well under provi-sioned (right)speed, so that should not have caused the problem.
Now you can go to the end-to-end circuit view (left).The complaint was for a call between Boston and Minneapolis, so you look at that individual circuit. Looking at the protocol distribution, it appears that SIP usage is consistent over the past two hours, so the application was flowing between the two cities.
In this scenario, SIP and the ERP system (Oracle) are to receive the highest priority CoS (Real Time) over the MPLS-based network. By drilling into the real-time CoS view, you can see both SIP and Oracle are relatively consistent in the amount of traffic from Boston, however, only Oracle traffic was coming from Minneapolis (below).
By drilling down into other CoS views, you can see that SIP traffic from Minneapolis is set at Best Effort (above).
During the set up for the VoIP deployment, a mistake was made at the Minneapolis router and the SIP application was being tagged with the wrong CoS setting. By using Visual UpTime Select, you have the tools and visibility to quickly determine what might be causing poor performance of VoIP - or for that matter, any other data application. In this scenario, the problem could have been isolated, pinpointed and resolved in a matter of minutes instead of the hours or days it takes many enterprises.
Conclusion
VoIP deployment is gathering speed throughout enterprises of all shapes and sizes. Too often, the impact of a VoIP implementation is not proactively addressed by both the traditional voice and data groups. Taking into account the six steps for holistic lifecycle management will greatly reduce the number of landmines associated with VoIP deploy-ments. Utilizing this holistic approach will help you maximize performance for the new VoIP calls as well as better manage other data applications across your converged infrastructure. Visual UpTime Selectis a complete solution that enables you to manage and optimize your entire infrastructure – ranging from VoIP to video to traditional data applications. By leveraging actual end-user traffic with up to a one-second granularity, Visual UpTime
Selecthelps you assess network readiness. Then with the complete Layers 1-7 visibility and troubleshooting toolset, you can monitor, manage, validate and report on the performance of VoIP and other applications. All of this detailed information will allow you to proactively control the performance of your network and applications. Now your organization has successfully bridged the gap between traditional data and voice groups and achieved a smooth VoIP deployment across the entire enterprise.
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