Driving The Growth Of Private IP Services
BY BOB NORBERG & PETER
As the market for frame relay services matures, service
providers must grow revenues against increased levels of competition,
leading to intense pressure on margins. At the same time the emergence of
new services based on the ubiquity and low cost of the public Internet have
added further pricing pressure. While robust site-to-site IP-VPN services
across the public Internet are on the verge of becoming a viable choice for
many large business customers, an increasing number of small to medium-sized
businesses are adopting IP-VPNs. Meanwhile their Fortune 1000 counterparts
evaluate the technology for large-scale deployment, in pursuit of
potentially significant cost savings.
In response to the drive towards native IP connectivity services, over
both public (Internet) or private (frame relay/ATM) transport media, major
frame relay providers have introduced new Private IP services. These
services are sometimes called ï¿½IP-aware frame relay services.ï¿½ These
services, typically based on MPLS and DiffServ technologies, offer a range
of advanced IP service enhancements to the installed base of frame relay
customers. This approach brings the benefits of low migration effort,
inherent security, and reliability, further differentiating frame-based
services against potentially less expensive, Internet-based alternatives.
The Main Drivers Behind This Growth Are:
- Improved disaster recovery ï¿½ Every enterprise is (or should be)
concerned about disaster recovery plans. IP networks can more easily
recover from ï¿½site downï¿½ situations. Rerouting IP addresses to a new
location is easier than re-establishing a large number of frame relay
- Desire for native IP-based services ï¿½ The increased use of Web and
IP-based applications drives the need for IP-aware networks. With more
applications transiting the enterprise WAN, network managers need more
control over how WAN bandwidth is used. They need to ensure that lower
priority applications, like e-mail and Web surfing, do not impact
mission critical applications, such as CRM or database access. IP
features such as class of service (CoS) allow the network manager to
properly engineer his network bandwidth.
- Reduced WAN complexity ï¿½ The use of IP routing, rather than frame
relay PVCs, simplifies the configuration effort for enterprise access
routers, resulting in IT staffing cost savings.
- Increased meshing of frame relay-based networks ï¿½ IP applications
such as VoIP, are driving an increasing need for branch sites to
communicate directly to each other (mesh topology), rather than through
a central site (hub and spoke topology). Private IP services eliminate
the meshing costs incurred with traditional frame relay services.
- Continued skepticism over use of the public Internet for
mission-critical networking ï¿½ Private IP enables a VPN to be
established across the frame relay infrastructures. Frame relay is
inherently more secure than the public Internet, while reliability is
less likely to be compromised since traffic typically resides on a
single frame relay network rather than transiting a variety of ISP
Guaranteed Service Is Key
Guaranteed service quality is a key component to the success of Private
IP Services. Before enterprises will place mission-critical traffic on IP
services, they will need guarantees on the quality of service (QoS). They
need reliability and predictability. Each enterprise has a wide variety of
applications, all of which share the same WAN connection. For proper
operation over the WAN, each application has specific expectations for the
available bandwidth, packet loss, and delay. (Table 1 highlights some common
applications and their sensitivities.)
In general, if the WAN does not operate as expected, applications become
unusable. What is the impact to voice quality if a large file transfer
preempts voice traffic from using the WAN? At best, the quality of the call
may seriously degrade. At worst, the call will be dropped. Private IP
services will typically manage the quality of the connectivity by using the
class of service (CoS) mechanisms built into IP. IP CoS enables the customer
to allocate a defined portion of bandwidth to a specific type (class) of
traffic. This is at once appealing ï¿½ because of the added flexibility and
bandwidth usage it brings ï¿½ and necessary, since IP traffic connections do
not have an assigned amount of bandwidth in the same way as frame relay PVCs
have a Committed Information Rate (CIR). Therefore, the ability to
differentiate traffic and guarantee performance is required to meet the
enterprise requirements of reliability and predictability and is an integral
part of a Private IP solution.
The Challenge: Performance Management
So we know that IP has the CoS mechanisms to provide an acceptable
quality of service. However, in order for service providers to provide SLAs
that address IP QoS, they must be able to monitor, measure, and guarantee
the IP connection behavior, from end to end (see Table 2).
- Need the ability to measure total
throughput, both ingress and egress, for each class of service.
- Has the correct percentage of
bandwidth been assigned and delivered for a given traffic class?
- Need the ability to measure
throughput, above/below CoS policing thresholds, for each class of
- Is site-to-site IP connectivity
- Need the ability to verify IP
connectivity between subnets.
- Is the site-to site IP connection
meeting the defined performance criteria or SLA?
- Need the ability to measure latency,
availability, and packet delivery ratio.
- Do the SLAs and performance
information reflect real-world network performance as seen by the
- Need the ability to collect and
measure all performance data at the customer location.
- Needs SLAs that are based on a clear
"IP demarc" at the customer location.
At the same time, the service provider is under constant pressure to
reduce their operating expenses. How can service providers guarantee
performance while reducing operational support costs? (See Table 3.)
- Reduce MTTR (mean time to repair) by
reducing problem isolation time.
- Operations staff requires real time
access to remote site performance data at the central operations
- Reduce cost of Operational support.
- Eliminate the need to technician
dispatches to resolve service problems.
- Verify that IP service has been
provisioned correctly between service demarcation points.
- Toolset to remotely verify IP
connectivity between subnets.
- Avoid the delays inherent in finger
pointing between service providers and enterprises.
- Enterprise and service provider must
be using the same data to troubleshoot problems.
Private IP services have many benefits that enterprises are looking for.
However, before enterprises migrate to Private IP, they need guaranteed
performance, which is achieved through CoS. In order to manage CoS and
guarantee performance, usage and performance data needs to be collected from
every site in the network and needs to be available to both the enterprise
and service provider for CoS service level validation. Additionally, in
order to guarantee performance in a timely and cost efficient manner, usage
and performance data needs to be available to both the enterprise and
service provider for collaborative operational troubleshooting and the data
needs to be available in real time.
If performance management is included in the Private IP service, it will
drive growth in the emerging Private IP services market.
- Enterprises will obtain the reliability and predictability of frame
relay along with the flexibility of IP.
- Service providers will be able to develop differentiated and/or
- Service providers will be able to provide an IP demarcation point that
clearly delineates the point of service delivery at the customer
- Service providers and enterprises can validate SLAs from a
- Service providers and customers will have collaborative performance
views, thus reducing operational costs, increasing customer
satisfaction, and improving customer relationships.
Private IP services will only be successful if both the enterpriseï¿½s
and service providerï¿½s requirements for performance guarantees and service
manageability are met. Private IP services must be designed and offered such
that performance is managed and guaranteed in a cost-effective manner in
order to make the service easy to sell and easy to run. Thus, one of the key
ingredients for the success of Private IP is performance management, which
must be viewed as a mandatory element of any Private IP service offering. c
Mr. Bob Norberg is director of Private Transport Services at Visual
Networks and Mr. Peter Luff is director of Service Creation at Visual
Networks. Their focus is on developing WAN performance management solutions
that help increase network reliability and revenues and creating NSP
services around products that dramatically reduce operational expenses and
the total cost of ownership for enterprise and service provider customers.
For more information visit the companyï¿½s Web site at www.visualnetworks.com.
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