Specifications

4
4-46
McDATA Products in a SAN Environment - Planning Manual
Implementing SAN Internetworking Solutions
routed SAN connection ensures disruptions at one site are
isolated and not allowed to propagate to other locations. This
connection does not support native FCP or FICON operation.
Figure 4-11 SoIP Extended-Distance Connectivity
Several network service providers provide long-distance IP or GbE
network transport services. Long-distance circuits are common. The
technology provides low overhead, low to medium bandwidth,
point-to-point transport of storage traffic, and is a cost-effective
choice for remote data replication.
Technology
Comparison
Figure 4-12 illustrates the complex relationship between RTO, RPO,
and extended-distance transport technology options. Extended-
distance operational modes (RDR/S and RDR/A) are directly
associated with the transport technology choice. Note there is
substantial overlap in the functionality provided by transport
technologies and no single transport technology satisfies all BC/DR
requirements. Comparison factors to consider are:
• Repeated or unrepeated dark fiber - This technology supports
medium-bandwidth, low-latency applications with short RTO
and RPO requirements. Applications include real-time disk
mirroring (RDR/S or RDR/A) over short to medium
metropolitan distances. Unless one or more SAN routers are
included in the extended-distance link (native FCP only), the
technology is vulnerable to disruptions caused by fabric or link
problems.