This white paper discusses the most common VPN technologies and highlights hidden costs, which should be considered when deploying a VPN. Network meshing and the addition of subsequent nodes are automatic functions of “connection-less” technology, including MPLS and IPSec. However, Frame Relay, a “connection oriented” technology, requires separate “permanent” virtual circuits to be manually programmed, in order for each node to be meshed.

1. WHITE PAPER
Analyzing MPLS from an ROI Perspective
Site Interconnection In most cases, a Virtual Private functions of “connection-less”
Network (VPN) is considered a means technology, including MPLS and IPSec.
of connecting various locations using However, Frame Relay, a “connection-
a public or private IP network. oriented” technology, requires separate
Increasingly, businesses require a fully “permanent” virtual circuits to be
meshed network permitting “any to any” manually programmed, in order for
connectivity. It is important to determine each node to be meshed. Network
the need for a meshed network, as the expansions are time consuming and
resources and costs associated with necessitate the need for accurate record
creating and maintaining a meshed keeping and skilled IT resources.
network are directly impacted by the The amount of resources required
specific VPN technology deployed. increases exponentially as the number
This white paper discusses the most of sites in the network increase.
common VPN technologies and
highlights hidden costs, which should
be considered when deploying a VPN.
Network meshing and the addition
of subsequent nodes are automatic
Throughput Speed Throughput speed results from with 768K of bandwidth, but a CIR
a combination of the connecting with 128K of bandwidth. (CIR must
network circuits’ bandwidth and the always be equal to or less than the port
effects of any congestion that may bandwidth.) It is the CIR rate that will
exist within the network. It is therefore fundamentally affect the price being
important to understand the manner charged for the Frame Relay circuit.
in which bandwidth is managed within
different network types. Under normal circumstances, the full
768K of bandwidth may be available
In regards to Frame Relay, Permanent for use. However, when congestion
Virtual Circuits (PVCs) are established occurs within the carrier’s network,
and maintained between sites. data that exceeds the CIR would be
End-users subscribe to a minimum deemed ‘discard eligible,’ because
bandwidth, Committed Information the throughput of VPN circuits
Rates (CIRs), which is contained within under congestion is limited to the
the PVC. For example, over a Frame CIR bandwidth.
Relay network, you could have a PVC
© Windstream 2012
DATE: 3.15.12 | REVISION: 6 | 009573_Analyzing_MPLS_ROI_Perspective | CREATIVE: MF | JOB#: 9573 - Analyzing MPLS from a ROI Perspective | COLOR: GS | TRIM: 8.5” x 11”

2. WHITE PAPER
Throughput Speed Under these conditions, data marked as discard eligible would need to be
(Cont.) retransmitted, which is unacceptable for time sensitive or real-time applications.
Applications such as VoIP, which are latency sensitive, will experience static, crackling,
or will drop altogether. Since MPLS does not require PVCs with CIR, congestion is
handled more efficiently. The following diagram demonstrates how full port speed
would be available to overcome the congested conditions under MPLS or IPSec. With
Frame Relay, only the bandwidth of the associated CIR would be available; therefore,
congestion recovery would typically occur faster in a MPLS or IPSec VPN. It is
important to consider how end-user business could be affected by congestion.
Customers should select the type of While an equivalent Frame Relay
VPN that best matches the applications PVC may cost less than or equal to
being deployed. For example, if real-time that of MPLS, an equivalent CIR will
transactions are being processed (i.e. generally result in increased Frame
point of sale transactions), congestion Relay circuit costs.
between nodes may be deemed
unacceptable. Any costs associated with
provisioning a higher capacity network
may be offset by the additional business
gained as a result.
© Windstream 2012

3. WHITE PAPER
Data Prioritization The type of network being adopted Although Frame Relay allows for data
needs to match the application being prioritization, ‘Priority PVCs,’ which are
deployed. While Voice over IP available from some vendors, add
exemplifies the classic need for real- substantial IT resources and associated
time data prioritization, to avoid dropped costs. Implementing ‘Priority PVCs’
calls and transmission distortion, there is not automatic; manual intervention
are many scenarios in which data needs is required in many cases at both the
to be prioritized in order for businesses customer level and at the carrier level. In
to function efficiently. Internet surfing an MPLS environment, data prioritization
or e-mail should take lower priority in is fundamental. Quality of Service (QoS)
comparison to point of sale transactions, facilitates packet prioritization, and with
to ensure that a business is capable of its relatively simple implementation, is
generating maximum revenues. invariably a cheaper solution.
Security MPLS and Frame Relay are equally premium over MPLS and requires
secure. Frame Relay utilizes Data Link specific hardware configurations. After
Circuit Identifiers (DLCIs) to address studying various MPLS white papers
traversing data packets, whereas written by technology manufacturers
MPLS uses tags or labels. IPSec is and IT managers, many healthcare
often adopted by organizations that are organizations are becoming comfortable
required to comply with HIPAA, since claiming HIPPA compliance when
IPSec relies on encrypted data transfers. utilizing MPLS VPNs.
However, IPSec tends to carry a price
Remote Access IPSec allows access to the customer’s However, IPSec does not provide
corporate VPN from remote locations. data prioritization, because traversing
This encryption method is seen within packets are encrypted, and as such,
the industry as the preferred method is not generally suitable for real time
of connection, ensuring data is not applications.
compromised prior to entering the VPN.
© Windstream 2012

4. WHITE PAPER
Disaster Recovery MPLS resides on an IP over SONET fails, the customer is faced with the
& Reassignment network and can automatically route following question: should he invoke
around points of failure to a disaster circuit reassignment and incur the cost
recovery location within the meshed associated with it, or should he wait to
network. However, with a Frame Relay see if the failure could be quickly
network, connection paths are pre- rectified? Acting too soon could incur
determined; PVCs need to be manually unnecessary costs, but acting too late
reassigned to the recovery site by the could negatively affect business. In
network provider and IT resources at addition, once the problem is resolved,
the end-user level. While providers may it is likely that the network would have
offer a ‘PVC Redirection Service,’ it is to be reassigned back to its original
essentially a manual reassignment. The configuration, incurring additional costs.
time to complete reassignment increases Under an MPLS configuration, the
exponentially as the number of nodes situation would have been automatically
in the network increases or the need to resolved, since PVCs do not exist.
mesh nodes increases. Network resilience is therefore greater
with MPLS than Frame Relay.
An intermittent failure within a Frame
Relay network can leave a business in
an undesirable predicament. If a circuit
Strategic Planning All market reports show that Frame applications, such as point of sale
Relay is an aging and declining transactions, reservations, etc, take
technology, unable to match the rich priority over such items as Internet
feature set that MPLS offers. MPLS is browsing.
the de-facto standard for future services
and for applications requiring packet MPLS also permits consolidation of
prioritization. Packet prioritization is Voice and Data services, thereby
essential in the Voice over Internet reducing communications overhead.
Protocol domain, preventing clipping Frame Relay is purely a data network,
and distortion and ensuring prioritization which was not designed for convergence.
of data transfers. Regardless of VoIP’s
presence, good business practice
dictates that priority business
© Windstream 2012

5. WHITE PAPER
Conclusion There are hard and soft costs associated the highest level of efficiency and
with a VPN deployment. While hard business continuity with minimal human
costs, such as circuits and CPE, are intervention become an increasingly
easy to measure, soft costs, such as desirable proposition. While other forms
IT resources and throughput, are of VPN have desirable characteristics,
equally important. only MPLS provides the network
intelligence businesses demand with
As technology progresses and the reassurance of future capabilities.
businesses look towards technology With its ability to reduce in-house IT
to keep them at the leading edge of resources, coupled with its inherent
their field, the deployment of networks resilience, MPLS provides the most cost
with embedded intelligence to enable effective and beneficial VPN solution.
009356 | 3/12 © Windstream 2012