Specifications

Bankway Network Standards Guide - Client Server Environment
This constitutes a trade secret of Fidelity National Information Services, Inc. 03/08 Research & Development
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Connecting a router to a WAN requires an interface device called a DSU/CSU. This may be
integrated into the router, supplied by the Common Carrier or owned by the bank. Often a
common carrier integrates data and voice traffic over a single link. In which case the DSU/CSU
must have an interface to the telephone system (PBX) and must be configurable.
WAN connections come in many varieties including wireless and satellite. For Bankway, the
current best practice is either dedicated links or Frame Relay. Dedicated links and Frame Relay
come in standard sizes: DS0 and T1. DS0 is 64Kbps or 56 in some implementations. T1, also
termed DS1, is 1.54Mbps. There is a third option in between called Fractional T1 with bandwidth
anywhere between the two. Sometimes a carrier will provision a T1 circuit to a location and use
part of the bandwidth for voice and the remainder for data.
Dedicated links are a fixed amount of bandwidth between two points. Frame relay is data broken
into fixed length groups called packets and transmitted through a common network.
Note: Some users have been concerned that their data is mixing with the data of other
companies, posing a possible confidentiality issue. The reality is that all traffic, both voice
and data, is mixed over the carrier's backbone. Proven multiplexing technology keeps it
all separated. As in any case, encryption helps insure confidentiality.
Generally Frame Relay is offered with two constraints: Committed Information Rate (CIR), which
is the bandwidth the carrier guarantees and Burst Rate which is the maximum speed of the link.
Frame Relay offers lower costs plus the ability to provision a connection to multiple endpoints.
This means that a Bank with multiple branches and a backup site can provision a single circuit to
each location and achieve the required connectivity.