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Monthly Archives: September 2011

My Network or Your Cloud?

Moving to Network Analysis in a Cloud Environment

Whether you are at a conference or reading the news, it seems like you can’t escape a conversation without a mention of cloud computing. No matter what the topic, from developers’ ability to deploy applications more easily on the infrastructure layer or embedding BI tools on the cloud, the cloud is seemingly affecting everyone in IT. But, what has been missing from the discussion, or so rarely discussed, is how cloud computing affects the monitoring and management of your network.

It doesn’t matter if your server is located in your data center or in the cloud, the only thing that’s changed from a network perspective is that the blame has shifted; there is still a need to monitor and analyze your network traffic. Now when you discover a problem is occurring on the application side, you have to deal with multiple external vendors, which can be a headache. Some of this can be averted though. And it first starts with the initial shift to the cloud.

A successful transition to the cloud will be one where the organization has a clear understanding of their current network. This includes establishing and understanding network performance baselines, especially for the performance of critical network traffic and applications for hourly, daily, and weekly cycles. Special attention should be given to verifying the performance of transactions that interact with multiple applications, since this is likely to be a challenging area once the applications are moved to the cloud. Other metrics to consider include packet size distribution, latency, and protocol and node usage over time. Knowing these cycles will help you determine your application and network utilization. This information is critical in determining exactly what is required for a cloud computing vendor to maintain, and hopefully improve, the performance that users currently experience.

Remember that shifting application servers to another location does not always make the most sense, and before you make the shift, keep in mind two major issues you may face: latency and security. Latency typically increases when you move to the cloud since the distance to application and data servers can increase greatly, along with the number of hops for data packets. And with the move to the cloud  you lose a lot of control in improving latency.

As for security, make sure that you clearly understand your cloud provider’s security policies. The cloud vendor is storing and processing highly sensitive data and applications, so the stakes are high. It is imperative to clearly understand the cloud vendor’s security policies and procedures before contracting its services, and any appropriate verification testing should be implemented within the organization to ensure these policies are not violated.

Once your applications are in the cloud, monitoring and analyzing your network will help you compare against performance claims from cloud vendors. You can verify whether your cloud vendor is living up to their service level agreements, and act as a sort of ‘watchdog’ if they are not. You’ll be shifting from managing your own infrastructure to managing service availability and performance.

For more information on managing your applications on the cloud, check out this five-minute video:

How to Conquer the Complexities of Switching to 802.11n

There is no doubt that 802.11n brings a high level of performance when compared to older a/b/g WLANs. Using multi-antenna and multi-radio MIMO capability allows data to be transmitted over multiple data streams in the same 802.11 channel — doubling, tripling, and even quadrupling throughput. Higher throughput opens up a new world of applications over wireless, including voice and video; and smart phones are already available to gobble up the content.

But these performance enhancements run parallel to the complexities of 802.11n. While manufacturers and industry organizations strive for interoperability, 802.11n still requires an educated consumer, especially for enterprise deployments, to ensure that incompatibilities are not designed or introduced into existing WLAN infrastructures.

Below are common issues that you may face when switching to 11n, how you can easily solve these issues, and questions you should ask your network monitoring provider and network equipment manufacture before you make the switch.

Mixed Mode Deployments

If you are deploying 11n, and want to take full advantage of it, you need to have all 11n gear. That’s not to say 11n isn’t compatible with existing a/b/g technology, because it certainly is. But once users hear that 11n is deployed, they expect all the benefits, and if they’re still using older technology to connect into 11n APs they’ll wonder what all the hype is about. If there are operational or financial reasons for designing for mixed modes, be sure to set appropriate expectations for users, and be extra vigilant in testing and verifying the performance of both the a/b/g and 11n users to be sure the overall system is performing as designed.

Compatibility Within 11n Greenfield Deployments

Even if you’re going all 11n, you need to carefully analyze the specifications for all of your components, including APs and wireless clients, to ensure complete compatibility and ultimate performance.

The typical designation for the specific 11n capabilities of a device is: NxM:n, where N is the number of transmitting antennae, M is the number of receiving antennae and n is the maximum number of data streams the device is capable of using. Note that just because a device is “3×3” that does not automatically mean it is also capable of 3-stream operation (and the corresponding 450Mbps data rate). For 3-stream operation the specification should be 3×3:3. If the manufacturer does not include that detail (most don’t on their packaging) then pay careful attention to the maximum throughput the manufacturer advertises for the device. If it’s 150Mbps, it’s a 1-stream device. If it’s 300Mbps, it’s a 2-stream device. And if it’s 450Mbps, it’s a 3-stream device. To take full advantage of maximum data rates, both the AP and the client must be capable of the same number of data streams. If your AP is capable of 3 streams but you have some clients that only have 2-stream wireless adapters then those clients will only be able to connect at 300Mbps maximum.

The same holds true for network monitoring. If you have devices that are capable of 3-stream operation, you must use network analysis software with a 3-stream capable wireless adapter to capture any 3-stream data in the network.

Inability to Troubleshoot Due to Settings and Modes

11n uses a combination of technologies in addition to MIMO to achieve superior data rates. These include channel bonding (also known as 40MHz mode), aggregation, and short and long guard intervals. Now we have 4 variables that can be applied in many, many different combinations, making 11n analysis extremely complex. Users of network analysis software, like OmniPeek, often have difficulty capturing all of the 11n data when they first upgrade. It’s critical to understand the maximum capabilities of your APs, as they will negotiate the optimum combination of settings with each associated client. Once these maximum capabilities have been understood through an analysis of each AP’s configuration settings, you can properly determine the appropriate wireless adapter and settings to be used for wireless network analysis.

Whether you already have 11n in place or you are thinking about moving, make sure you educate yourself about its complexities and determine if the ROI is there. If your current 802.11a/b/g is not fully depreciated, it might not be the right time for you to switch.

Announcing Our Fall Roundtable Series

This Fall we’re continuing our popular half-day Network Performance Roundtables, a free educational seminar followed by a complimentary lunch at a local restaurant: Il Fornaio, Lindey’s, Maggianos, or Papa Razzi.

Our focus this season is Visibility into What’s Happening… NOW! Our technical experts will walk you through a typical troubleshooting scenario and then explore why you need 24/7 monitoring and how to achieve a true picture of what’s happening in your network.

Employing virtual devices to save on hardware costs? Are you capturing all of your virtual traffic? You know, the traffic that never crosses a physical network segment. Just because you can’t see it, doesn’t mean everything is running smoothly.  With heavily utilized 10G network segments rapidly becoming the norm do you have visibility into microbursts? Got real-time IP-based communication (RTIPC)? Waiting for the replay when your users are experiencing problems to find out what’s wrong is too late; you need real-time visibility to correct the problem on the fly.

At the end of this roundtable, you’ll be armed with tips and tricks for realizing full capture and real-time visibility.

Agenda:
9:45 Registration
10:00 Welcome and Introductions
10:15 Visibility into What’s Happening… NOW!

  • WLAN Capture and Analysis
    • Troubleshooting Wired and Wireless Simultaneously
    • Troubleshooting Roaming Issues
  • Configuring Your Virtual Network for the Realities of Network Analysis
    • Understanding Your Options
    • Monitoring and Analysis for Large Virtual Environments
  • VoIP Monitoring, Analysis, and Troubleshooting
    • Handling Conflicting Demands of Data and VoIP
    • Rethinking the Metrics: What do MOS, Jitter, and Latency Mean?
  • Implementing Distributed Packet Capture and Methodologies at 10G
  • Overview of WildPackets Product Lines
  • Questions

12:00 Lunch/ Q&A Roundtable Discussion

We plan to have a highly interactive session featuring real world examples and best practices for monitoring, analyzing, and troubleshooting wireless networks, virtual environments, VoIP calls, and 10G networks. Have a specific question you’re dying to know the answer to? Let us know and we’ll be sure to cover it in your session.

Attend a roundtable in your area and learn how to:

  • Determine whether the wireless network or the wired network is at fault
  • Configure your virtual network for the realities of network analysis
  • Troubleshoot poor voice quality with WildPackets OmniPeek
  • Implement distributed packet capture and methodologies at 10G

Dates and Locations

·         Tuesday, September 20: Las Vegas, NV
·         Wednesday, September 21: Birmingham, AL
·         Thursday, September 22: Austin, TX
·         Tuesday, September 27: King of Prussia, PA
·         Thursday, September 29: St Louis, MO
·         Tuesday, October 4: Atlanta, GA
·         Wednesday, October 5: Chicago, IL
·         Thursday, October 6: Burlingame, CA
·         Tuesday, October 18: Hackensack, NJ
·         Thursday, October 20: Portland, OR
·         Tuesday, October 25: Columbus, OH
·         Wednesday, October 26: Cleveland, OH and Plano, TX
·         Wednesday, November 2: Houston, TX
·         Thursday, November 3: Milwaukee-Wauwatosa, WI and Orlando, FL
·         Tuesday, November 8: Burlington, MA
·         Wednesday, November 9: Bellevue, WA

Don’t see a venue near you? Let us know you want us to visit your area. We’ll be planning our Winter and Spring Roundtables shortly.