Connecting to an IPv6 network

z/OS® Communications Server TCP/IP supports direct attachment to IPv6 networks in the following ways:

IPAQENET6 interface type: TCP/IP attaches to an IPv6 LAN by way of OSA-Express in QDIO mode, using either Fast Ethernet or Gigabit Ethernet. A single physical LAN can carry both IPv4 and IPv6 packets over the same media. While the physical network is shared, from a logical view there are two separate LANs, one carrying IPv4 traffic and one carrying IPv6 traffic. A single OSA-Express port can be used to carry both IPv4 and IPv6 traffic simultaneously. TCP/IP supports three CHPID types for IPAQENET6 (OSD, OSX, and OSM). If your configuration includes OSX or OSM CHPID types, see the information about TCP/IP in an ensemble in z/OS Communications Server: IP Configuration Guide for additional considerations for these CHPID types.
MPCPTP6 interface type: TCP/IP can directly communicate with other IPv6 z/OS Communications Server TCP/IP images, using ESCON® channel-to-channel adapters, XCF connectivity (if the stacks are in the same sysplex), or the IUTSAMEH facility (if the stacks are on the same LPAR).
IPAQIDIO6 interface type: TCP/IP can directly communicate with other IPv6 z/OS Communications Server TCP/IP images and Linux for System z® images using HiperSockets™ connectivity. This applies only to stacks running on the same central processor complex and running on a zSeries® server that supports IPv6 HiperSockets.
IPCONFIG6 DYNAMICXCF: IPCONFIG6 DYNAMICXCF provides HiperSockets connectivity if available, XCF connectivity (if the stacks are in the same sysplex), or the IUTSAMEH facility (if the stacks are on the same LPAR).

Guideline: All of these interface types can be used for LPAR-to-LPAR IPv6 communication, best performance is achieved by using the IPAQIDIO6 interface type (if both stacks meet the criteria previously listed). The performance of the other interface types varies with the speed of the underlying media.

For stack-to-stack communications within a single LPAR, the MPCPTP6 interface type (using IUTSAMEH) provides the best performance.

To transport IPv6 traffic to another host, z/OS TCP/IP must send traffic using native IPv6 packets. Note that when communicating with another IPv6 host, a router within the network might tunnel the IPv6 packet across an IPv4 network to a remote IPv6 LAN or host. However, z/OS Communications Server TCP/IP cannot be the tunnel endpoint, and the tunneling by an intermediate router is transparent to z/OS Communications Server TCP/IP.