Expand Configuration and Management Manual (G06.24+)

Planning a Network Design
Expand Configuration and Management Manual—523347-008
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Internet Protocol (IP) Networks
Internet Protocol (IP) Networks
The IP suite is an important industry standard. Expand-over-IP allows NonStop
systems to be interconnected via inexpensive IP-based routers, making a separate
Expand network unnecessary.
Expand-over-IP uses a NonStop TCP/IP process to implement the TCP/IP protocol
stack. The Expand-over-IP line-handler process communicates with the NonStop
TCP/IP process through the shared memory of the QIO subsystem.
The major benefits of Expand-over-IP connections are
•
Cost-effectiveness. Expand-over-IP allows you to route Expand paths over
industry-standard IP routers. IP-based networks allow many applications to share
high-speed links.
•
Flexibility. No modifications need to be made to Expand applications to allow them
to run over IP networks. A NonStop server that can access an IP network can be
part of the Expand network.
•
Fault-tolerance. You can use the multi-line path feature to enhance the reliability of
Expand-over-IP connections. Using this feature, you can configure up to eight
parallel lines between nodes.
•
Passthrough capability. Packets sent over an IP network path can be forwarded to
another Expand line-handler process, which can be of a different line type and in a
different processor.
As of G06.20, NonStop TCP/IPv6 is available for Expand to use. In addition to
providing the use of IP version 6 communications, this product includes all the Parallel
Library TCP/IP (TCP/IP/PL) functionality made available in G06.08.
You can still choose to run Parallel Library TCP/IP, but you cannot run Parallel Library
TCP/IP and NonStop TCP/IPv6 at the same time. You can run NonStop TCP/IP and
NonStop TCP/IPv6 at the same time, however.
NonStop TCP/IPv6 has three operating mode: INET, INET6, and DUAL. In the INET
mode, only IP version 4 communications are supported and the product is similar to
the Parallel Library TCP/IP product with the addition of some new features. In DUAL
mode, both IPv4 and IPv6 communications are supported. In INET6 mode, only IPv6
communications are supported.
One of the differences between the conventional NonStop TCP/IP subsystem and both
Parallel Library TCP/IP and NonStop TCP/IPv6 for Expand is that there are no
matching-processor configuration requirements for the TCPSAM and TCP6SAM
processes and the Expand line-handler processes. Another difference is that when you
Note. On NonStop K-series servers, Expand-over-IP line-handler processes are only
supported on D40 and later systems; however, data received by an Expand-over-IP
line-handler process can be forwarded to a different type of Expand line-handler process on a
non-D40 system. In addition, data received by an Expand line-handler process on a non-D40
system can be forwarded to an Expand-over-IP line-handler process.