AIX Version 4.3 Differences Guide

The following are the new functions provided Bind Version 8.1.2:
• Secure dynamic DNS updates
Currently, BIND offers only the unsecured RFC 2136 update protocol. This is
an insufficient offering to customers desiring to implement a dynamic DNS
environment in their networks. The secure update protocol is added as the
solution for RFC 2136's insecure shortcomings and to provide backward
compatibility with current AIX dynamic DNS customers.
• Incremental zone transfer
Implement the RFC 1995 Incremental Zone Transfer protocol. This protocol
defines a method through which secondary DNS servers can update their
existing zone data to incorporate all the cumulative changes to the primary
zone since the last transfer. This protocol supersedes the performance of
ordinary zone transfers by limiting the amount of network traffic between
primary and secondary DNS servers and the subsequent computation time in
incorporating an entirely new zone. The protocol ensures that incremental
zone transfers can be sent to indicate changes from both dynamic updates
and from zones changed on disk (those reincorporated through a refresh
signal or server restart).
• Notify
Implementing the RFC 1996 Notify process. This is a method by which the
primary DNS server can indicate to its secondary nameservers that zone data
has been updated. This decreases the time periods in which a secondary DNS
server will have data out of synchronization with its primary DNS server.
• File Conversion Utility
Extending the configuration file conversion utility to support IBM functional
additions to previous BIND releases. This involves mapping the dynamic
keywords of previous named.boot files to a functional equivalent in the
named.conf configuration file.
• Proprietary protocol for secure updates of dynamic notify dynamic zones.
Bind 4.9.3 is available using named4. Bind 8.1.2 uses named8.
7.9 Web Server Performance Improved (4.3.2)
Web server workload has a large number of small file operations. In smaller file
operations, the cost of processing connection set-up/tear-down far exceeds the
data touching (such as copy or checksum) operations. By reducing the number of
packets that are sent or received for connection set-up/tear down, performance is
improved. IBM has developed a set of TCP changes to reduce the number of
packets from 9 to 7 or 6.
For Web transaction oriented environments using HTTP protocols, AIX Version
4.3.2 reduces the number of network packets that are exchanged between the
workstation and the server. This lowers the CPU packet processing overhead,
increasing server performance and capacity.
Networking Enhancements 173