iTP Secure WebServer System Administrator's Guide (Version 7.0)

Introduction to the iTP Secure WebServer

iTP Secure WebServer System Administrator’s Guide—523346-012

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TCP/IP Subsystem

The HP NonStop TCP/IP subsystem allows processes on a NonStop System to

communicate using the TCP/IP protocol. There are three versions of TCP/IP support

available; conventional, Parallel Library, and TCP/IPv6.

Conventional TCP/IP

In essence, conventional TCP/IP has one listening process on each port. The

conventional TCP/IP connections are managed by the Distributor process. The

Distributor receives all incoming requests for new connections from the TCP/IP

processes and used to previously distribute them to the iTP Secure WebServer, using

the NonStop TS/MP Pathsend facility. Beginning iTP WebServer 4.1, the Pathsend

facility were removed.

Parallel Library TCP/IP and TCP/IPv6

In essence, Parallel Library TCP/IP and TCP/IPv6 have multiple listener sockets on the

same port. Parallel Library TCP/IP and TCP/IPv6 allow the server direct access to the

communication environment from their own processors instead of having to

communicate via the processor that contains the HP TCP/IP process. This is done by

linking to a system library containing the TCP/IP procedures and allowing the server to

call the functions doing TCP/IP-related processing in its own context.

Running with the Auto-Accept feature, an iTP Secure WebServer no longer needs its

Distributor component. The httpd servers will assume the listening in addition to the

distributing functions of the Distributor. The Distributor server class will be completely

removed from the PATHWAY environment.

Running the iTP Secure WebServer relies on the properly configured Parallel Library

TCP/IP or TCP/IPv6 environments. Every processor specified in the Server CPUS

command (in the httpd.config configuration file) needs to be enabled to run Parallel

Library TCPIP or TCP/IPv6, as the case might be. In other words, the TCPMAN needs

to be properly configured and running. As a result, a TCPMON (the monitor process)

runs on every processor specified in the Server’s processor command.

Unlike the conventional TCP/IP subsystem, the Parallel Library TCPIP and the

TCP/IPv6 allow the iTP Secure WebServer to create a listening socket on each of

these processors. By creating a listening socket on each of these processors, the httpd

servers provide the listening capability for themselves. Therefore, mixing the Parallel

Library TCPIP or the TCP/IPv6 with conventional TCP/IP subsystems is not

permissible. If both TCPSAM process and conventional TCP/IP process are specified

as the transport service providers, the Auto-Accept feature will not be enabled. The iTP

Secure WebServer will be running as a conventional TCP/IP configuration.

IP CIP

The iTP Secure WebServer works the same way with IP CIP as it does with Parallel

Library TCP/IP and TCP/IPv6. However, IP CIP allows all the httpd servers to assume