TCP/IP applications refer to networked computers via their fully qualified domain names
(FQDN) and their IP addresses. Because IP addresses can change easily, SAS applications
that contain hardcoded IP addresses are prone to maintenance problems. To avoid such
problems, use of an FQDN is preferred over an
IP address. The name-resolution system that is part of the TCP/IP protocol is responsible for
locating the IP address that is associated with the FQDN.
SAS 9.2 introduced support for the Internet Protocol,
IPv6, which is the successor to Internet Protocol,
IPv4. Rather than replacing IPv4 with IPv6, SAS now supports both protocols. There will
be a lengthy transition period during which the two protocols will coexist. A primary
reason for the new protocol is that the limited supply of 32-bit IPv4 address spaces
was being depleted. IPv6 uses a 128-bit address scheme, which provides more IP addresses
than does IPv4.
Here are examples of an FQDN, an IPv6 address, and an IPv4 address:
d6292.us.company.com
db8::01
10.23.2.3
For details, see Internet Protocol Version 6 (IPv6) in SAS Language Reference: Concepts.