Layer 7 Load Balancing
One of the great things about late-model load balancing hardware is the ability to balance on data from the application layer (layer 7 of the OSI model). Traditional load balancers balance traffic based on the virtual IP that was assigned to a cluster. Requests sent to the virtual IP are routed to a destination based on the algorithm used on the nodes in that cluster. With layer 7 load balancing, specific information within the request itself can be used to balance the request to the appropriate destination.
INetU used this technology primarily on our Cisco ACE 4710 load balancers. This dedicated network appliance is capable of various layer 7 functions, ranging from simple keyword or response code health probes to full-fledged layer 7 load balancing. A common example of request-based decision making is static content hosting. Images, style sheets, scripts and so on may be served up by a content delivery network that is standalone from an application platform. To implement this, we can simply create a classification on the load balancers as follows:
class-map type http loadbalance match-any PICS
3 match http url /*.jpg
4 match http url /*.png
When the above is assigned to a policy map in a config, any traffic that matches the pattern will divert it to a serverfarm unique to that traffic. Any traffic not matching will be routed along the standard path to one of the many application server nodes it resolves to based on the conventional distribution algorithm.
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A couple months ago, Cisco refreshed its 2960 switch line. The 2960 switch line is their entry level datacenter access layer switch. Many people expected some minor hardware improvements, but nothing drastic. Cisco proved them wrong. With this refresh came a ton on new features and upgrades that have been brought down from Cisco higher end switches. Here is a list of some of the bigger increases from the older 2960 line:
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Cisco’s IPS/IDS solution has come a long way over the last couple years. Recently, Cisco updated their software version to 7. With this came one exciting new feature: global correlation. This feature is available on the standalone IPS sensors, as well as the ASA sensor plugins on the 5510+ – to name just a few…
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With the release of ASA code version 8.2(1), Cisco released AnyConnect Essentials and AnyConnect Premium. Since then, minor changes have been added to the product features as technology expands. AnyConnect version 2.5 is now available, and has added some performance and security enhancements to the 2.4 tree.
But, what are the major differences between these 2 options? Price, of course, as the premium tag denotes a premium price. But in terms of features, which one do you need? Let’s break this down, to help you purchase the license that best suits your needs, and also educate you on the available features within the AnyConnect product line:
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As companies are looking to cut costs, many ponder moving their infrastructure to a managed hosting environment rather than maintaining it themselves. Saving money is always an appealing option to any CEO, but the first questions always raised are, “How will our infrastructure respond if it is a hundred of miles away? Will our file sharing performance be hurt due it not being on the local LAN?”
These are all very good concerns and, in some cases, can be deal breakers for the company. But, there is help out there, and the solution is proven and being praised by many. That solution is Cisco WAAS.
Cisco WAAS, or Wide Area Application Services, allows you to centralize applications and storage in a managed host, while still maintaining LAN-like performance. And that is just the start of things!
WAAS allows you to:
- Save money by not having to have dedicated floor space locally for a data center.
- Not have data across many servers in many locations that is different everywhere.
- More efficiently use WAN connections, and prevent unnecessary upgrades to those circuits.
- Have the uptime and reliability for their servers that come with a Managed host, and not have to worry about issues like failures, MRO stock, support contracts etc.
Implementing WAAS is pretty straightforward. Depending on your exact needs, there are different models and implementation details, from a local module on an ISR router, to a full-fledged dedicated device. Here is how Cisco WAAS works the magic:
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