There is an unmistakable industry trend to offer every IT
function in the cloud, if at all possible. WAN Optimization (WANO) is no
exception. WANO is used to mitigate the effects of a WAN (low
bandwidth, latency, and packet loss) to get improved application
performance (fast end-user response time) and also to reduce the
bandwidth consumption itself. WANO in its most popular form is symmetric
in nature - an appliance called a WAN Optimization Controller (WOC) is
placed at each end of a WAN connection (at the data center and at the
branch).
WOCs
achieve their goal using a combination of techniques- compression,
de-duplication, caching, TCP optimization, and chattiness reduction at
the application level. These techniques are applied across the whole
segment of the WAN by the two WOCs. All the benefits of the WANO start
right in the access segment or the last mile at both ends of the
connection.
The issues with WOCs, particularly among small and
medium businesses, are their initial cost, ongoing maintenance, and
complexity of managing them in-house. CAPEX is always hard to come by
for small/medium businesses. Managed Service Providers (MSPs) can
alleviate this issue by offering a fully managed WANO service with
charges on a monthly basis. The OPEX model offered by the MSPs can be
called a "semi-cloud" solution from the customer point of view and
appears to offer comparable benefits of fully owning and operating the
WOCs without many headaches.
Another twist in this equation is
that WOCs may not be as efficient over the public Internet as opposed to
a somewhat expensive MPLS network. Small/medium businesses invariably
use Internet-based VPNs to construct WANs connecting their widespread
locations. So the MSP model may not always work satisfactorily -
especially in cases of customers with locations across the globe.
In
the last few years Cloud-based WAN Optimization (CWANO) providers have
emerged on the horizon (a company called Aryaka is leading the way).
CWANO vendors, in their basic service, avoid deploying any appliance at
all on the customer premises. The magic starts and ends at their
Points-of-Presence (POPs) in the cloud to which the customer locations
connect. Sophisticated and carrier-grade WOCs are deployed in the cloud
by the cloud provider. They also provide convenient web-based management
tools to configure the service and monitor the WANO results achieved.
The
OPEX model of pricing offered by CWANO providers is much cheaper than
owning and managing the WOCs. Customers don't need to buy expensive MPLS
connections as the solution runs over the public Internet. Is it too
good to be true?
Yes, a closer examination of the CWANO reveals
that the optimization takes place only in the middle segment of the WAN
journey - between the POPs. Nothing happens on either side on the last
mile. The claim is that the middle segment which can span continents for
international connections is often where the Internet performance is at
the worst (high latency and high packet losses) and that is where
optimization is needed. However, the end links also can significantly
affect performance, possibly due to low bandwidth.
The best way to
verify if "WANO in the middle" provided by cloud-based providers really
helps is to conduct a proof-of-concept and compare with the baseline
results. If we can also compare with the case of full WANO with WOCs at
either end, then we can make an apples-to-apples comparison.
But
the CWANO providers are also smart enough to hedge their bets. As an
option (many times at no cost), they can provide some kind of an
appliance at both ends and provide full segment WANO. In this case, they
are not a true cloud-based provider but more like an inexpensive MSP.
In
all fairness, the CWANO providers have enlisted many satisfied
customers with global locations. If you are planning to use CWANO, as
the saying goes, trust but verify.
Apsera Tech, a premium APM consulting company, has years of experience in WAN optimization, networking and application performance management.
It has helped Fortune 1000 companies in diverse industries such as
financial services, healthcare, manufacturing, and publishing in
planning/resolving critical business application performance issues like
slow application response time, WAN optimization and WAN acceleration.
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