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Cisco Remote Connection
Products
This chapter covers the selection of products for the central office, the branch office, and
the SOHO or RO. The key is to know where product families fit, not to memorize individual
product part numbers or codes. For instance, you can get by knowing the capabilities of the
3600 product family as compared to the 1600 product family, without getting into the
granular details of either.
The bulk of the information in this chapter leads the engineer to ask the right questions
when embarking on a new design. The points to consider include the following:
·
Availability
--The key question here is "Is there ISDN or DSL in my area, and can I
get it?" Because we are talking about Remote Access, it is not a given that the service
we might want is available.
·
Bandwidth
--What speed is needed for the applications that will use the link? It is
important that the bandwidth handle the client's requirements. In general, clients who
are extremely cost-conscience might look for solutions that are doomed to failure.
·
Cost
--This is one of the final selection criteria for an implementation. You must
explore
all
the WAN options available because costs can vary between regions. In
general, cost is directly related to the bandwidth requirement.
·
Ease of management
--Given any installation at any site, the cost of moves, adds,
and changes should be factored into the design. CiscoWorks is a good choice for
management software, but it is not your only choice.
·
Applications and traffic patterns
--This can be the most difficult task; however, it is
by far the most critical. For example, a remote law office repeatedly uploading and
downloading thousand-page documents can require a different solution than a remote
insurance agency that sends a few pages of client information and that accesses a SQL
database. The traffic patterns and needs define the bandwidth requirement, which in
turn drives the cost.
·
Backup needs and Quality of Service
(QoS)
--The need for backup links and QoS
are important. For instance, what is the cost of downtime? If the cost is high, your
high-speed Frame Relay circuit should be backed up by a low-cost ISDN line.
Another consideration is the cost of loss of service if a dial link fails. If this happens,
backup needs and costs should be weighed against the track record of the suppliers in
the area for a given access technique.