Tcp/Ip Protocol Stack - IBM AS/400e User Handbook Manual

AS/400 SMTP is enhanced with the following features:
• Increased simultaneous connection support. AS/400 SMTP is no longer restricted to a
maximum of 16 inbound and 16 outbound simultaneous mail connections. You can
tune SMTP depending on the mail load on your system, therefore enabling greater
scalability.
• Enhanced domain name system resolver support. The AS/400 SMTP client processes
all mail exchanger (MX) records returned by a domain name server query. This means
that there is less undeliverable mail when sending to large Internet Service Providers.
• New option to enable journaling for mail delivery status tracking and mail statistics.
• New option to require all mail received by AS/400 SMTP to be processed by the
AS/400 Mail Services Framework (MSF) to improve security.
• Enhancements for the automated retry of mail when dial-up connections are
established and finer granularity of mail delivery retry timing.
AS/400 TELNET enhancements allow TELNET to support secure TELNET sessions using
SSL.
Improved serviceability characteristics for TELNET, SMTP, and FTP reduce the impact to your
business when service is required.

TCP/IP Protocol Stack

In V4R4, performance of the TCP/IP protocol stack on the AS/400 system continues to be
improved. The result is significant improvements in capacity for TCP/IP users.
In addition, the AS/400 TCP/IP protocol stack contains two additional performance-related
TCP/IP Request for Comments (RFCs):
• RFC 1191: Path MTU Discovery
• RFC 1323: TCP Extensions for High Performance.
The implementation of these RFCs improves TCP/IP performance in many environments.
Chargeable Features of OS/400
IBM Print Services Facility for AS/400 (PSF/400) (#2691)
Print Services Facility for AS/400 (PSF/400), a feature of OS/400, provides support for
high-function Advanced Function Presentation (AFP), electronic printing and Intelligent
Printer Data Stream (IPDS) print management. With AFP, application output can be
transformed into fully graphical documents when electronic forms, image, graphics,
barcoding, lines, boxes, and text in a wide variety of fonts. This flexibility enables the
production of electronic documents that are more effective and enable the re-engineering of
Operating System/400, 5769-SS1
Operating System/400, 5769-SS1
511