IBM AS/400e, Руководство пользователя

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Operating System/400, 5769-SS1
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Operating System/400, 5769-SS1
– TCP/IP support
• Point-to-Point Protocol (PPP) synchronous and asynchronous communication
connections spanning low to high bandwidth connections to the World Wide Web
• Serial Line Internet Protocol (SLIP) asynchronous communication connections
allows inexpensive, limited bandwidth access to the World Wide Web
• Anonymous FTP support provides access to a restricted area of data on the AS/400
system that the public can access without a password or user identification
• Support for popular graphical FTP clients and Web server development tools
• Direct database serving to Web browsers, which allows DB2 for OS/400 data to be
queried and served (with graphics, if desired) to a Web browser using HTTP Server
for AS/400
• Additional network security, flexibility, and manageability are included in OS/400. All
of these features are configured with the Operations Navigator GUI. Some of these
technologies are also found in such firewall products as Firewall for AS/400.
Although the AS/400 system by itself is not intended to be a firewall (the Firewall for
AS/400 product requires a separate Integrated Netfinity Server), the addition of
these functions may eliminate the need for a separate a firewall product in some
cases:
– TCP/IP Packet Security : Selectively limits or journals network access to
applications and services with additional protection for AS/400 systems that run
sensitive applications or act as Web servers. TCP/IP packet security also helps
protect an entire subnetwork when the AS/400 system acts as casual router.
– TCP/IP Address Mapping and Hiding : When the TCP/IP addressing schemes or
networks conflict, or you need to hide all or part of the network topology,
network address translation (NAT) capabilities provide a solution. In addition,
TCP/IP masquerading allows all of the computers on one network to access
servers on another network by sharing a single TCP/IP address. Masquerading
is particularly useful when connecting to another network, such as the Internet,
using a dial-up link.
– TCP/IP Dial-on-Demand (DOD) Networking : Connections are made only when
there is a need to communicate. Dial-on-Demand is supported on all switched
network types and is particularly well-suited to ISDN with its fast call setup time.
It is also valuable for burst and infrequent traffic patterns, especially if you have
more remote locations than physical lines. With Dial-on-Demand, modem and
telephone line resources are not committed until an application attempts to
communicate with a remote site. Therefore, a small number of physical
resources can dynamically serve a large number of remote networks.
– TCP/IP Integrated Load Balancing : Virtual IP Addressing (VIPA) creates a
virtual TCP/IP address that is not associated with a physical network interface.