Visara CNA-8000 Planning Guide - Manual (Page 11)

CNA-8000 Migration and Planning Guide
707156-002 1-3
Using Multiple CNA-8000 Platforms for SNA Disaster Recovery
Using switched SNA definitions on the host with multiple XCA definitions across one or
more CNA-8000 platforms allows you to provide redundant data paths for critical
operations. For example using two different CNA-8000 platforms, the same downstream
SNA platform could reach its host definition through either of the SNA gateways,
providing that the downstream platform can be configured to take advantage of this.
Another possible arrangement would be to provide redundant paths on the upstream
ESCON or FICON connection by using two interfaces in the same CNA-8000, or
multiple Ethernet or Token Ring interfaces to the same or different upstreams. Some
products such as the Visara 1174 are capable of supporting an alternate SNA gateway as
a standard feature, making communication through redundant CNA-8000s seamless.
Providing Backup Strategies for OSAs
The CNA-8000 can provide a redundant pathway for an existing OSA, through an
ESCON or FICON interface. SNA traffic that would normally pass through an OSA to
access the host can typically be directed to pass through the CNA-8000 as an alternative.
Token Ring Option when a Token Ring OSA is not Available
The CNA-8000 can be used to provide direct access to the host for Token Ring platforms,
without having to deploy a router. The CNA-8000 can be equipped with as many as 3
Token Ring adapters to provide functions similar to an OSA through an ESCON or
FICON channel.
Integrated DLSw Support
The CNA-8000 is capable of providing integrated DLSw support. When DLSw is
configured on the CNA-8000 for the downstream connection, the data passing through
the Ethernet interface is in IP format instead of LLC. This option can be used to keep
LLC traffic off the local backbone completely. At the downstream location it is necessary
to have another DLSw capable device to strip the IP shell from the SNA traffic and
present the SNA traffic in a native SNA format (LLC, SDLC, etc) to the downstream
SNA platforms. The Visara 1174 product supports a form of DLSw allowing you to keep
LLC traffic off the remote LAN as well.
SDLC PU2 Platform Support
The CNA-8000 is capable of communicating with downstream PU2 platforms over an
SDLC serial link. The upstream connection utilizes the SNA Gateway feature to interface
to a switched VTAM PU2 definition. Both PU2.0 and PU2.1 platforms can be supported
through the SDLC lines. Communications speeds up to T1/E1 are possible, and multidrop
as well as point-to-point connections are supported.