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Selecting a WAN Connection Type for Remote Access Purposes

Application traffic

--You should know the type of traffic that is carried on the link. Is the

link primarily used for file transfer or email? What are the packet sizes? What type of
delay is acceptable? For example, if a file transfer takes two seconds over a LAN but ten
minutes over a WAN link, is this acceptable? Application traffic and the actions of your
customers are critical to your decision.

Once each piece of information has been gathered, router selection is easy because knowing
what needs to be done and how much has to be done by the router helps you select the right
router for the job.

Much of the information in the previous bulleted list could be considered common sense;
however, many consumers of WAN technology buy a big router because it is better than a small
router. The cost of any networking equipment is small compared to the monthly cost to maintain
the WAN service. The decision process should focus strictly on the usage and needs.

This section discussed that there is no one answer to what a customer needs. Each installation
and each design is unique to the situation that is being solved. The value-added reseller (VAR)
or integrator must focus on the business of the customer rather than the business of selling the
same router to each customer.

Selecting a WAN Connection Type for Remote Access
Purposes

Once you define customer needs, you must select carrier technology to support the applications
that are identified. For Remote Access, the choices (in descending order of speed and control)
are as follows:

Leased line

--A leased line gives the consumer complete control of the facility in terms

of what data is to be put on it. The customer effectively owns the bandwidth of the link.
This ownership offers high security and control to the customer; however, this is probably
the highest cost solution available. Although lease facilities with very high data rates (up
to multiple megabit) can be obtained, the issue is how much bandwidth, and at what cost,
the consumer is willing to purchase.

Frame Relay

--Frame Relay service probably carries the majority of business circuits in

the United States. With this service, the customer somewhat controls the resources being
used by specifying a Committed Information Rate (CIR) or guaranteed rate of delivery.
The Frame Relay provider, however, controls the latency or delay through the network,
and speed is a function of the provider's offerings. Speeds can range up to multiple
megabit transfer rates; however, they are generally available only up to T1 (1.544 Mbps).
With Frame Relay, the issue of cost is lessened because many companies share the
circuits.