Specifications

Implementing SAN Internetworking Solutions

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Implementing SAN Internetworking Solutions

Figure 4-12 SAN Extension Technology Comparison

• WDM - This technology supports high-bandwidth, low-latency

applications with short RTO and RPO requirements. Applications

include peer-to-peer computer clustering (grid computing) and

real-time disk mirroring (RDR/S or RDR/A operational mode)

over short to medium metropolitan distances. WDM scales to

higher bandwidths at a lower relative cost than SONET or SDH.

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.

• SONET and SDH - These technologies support medium-

bandwidth, medium-latency applications with short-to-long RTO

and RPO requirements. Applications include asynchronous disk

backup or tape vaulting over metropolitan to extended (intercity)

distances. Unless one or more SAN routers are included in the

extended-distance link (native FCP or iFCP), the technology is

vulnerable to disruptions caused by fabric or link problems.