Question & Answer
What is a HiperSocket?
FAQ: What is a HiperSocket?
From IBM Manual SG24-7798 -
HiperSockets, also known as internal Queued Direct I/O (iQDIO), is a hardware feature that
provides high-speed LPAR-to-LPAR communications within the same sever (through
memory). It also provides secure data flows between LPARs and high availability, if there is no
network attachment dependency or exposure to adapter failures.
HiperSockets can be used to communicate among consolidated servers within a single
System z server. All the hardware boxes running these separate servers can be eliminated,
along with the cost, complexity, and maintenance of the networking components that
Consolidated servers that have to access corporate data residing on the System z server can
do so at memory speeds, bypassing all the network overhead and delays.
HiperSockets can be customized to accommodate varying traffic sizes. With HiperSockets, a
maximum frame size can be defined according to the traffic characteristics transported for
Because there is no server-to-server traffic outside the System z server, a much higher level
of network availability, security, simplicity, performance, and cost effectiveness is achieved as
compared with servers communicating across a LAN, such as:
_ HiperSockets has no external components. It provides a very secure connection. For
security purposes, servers can be connected to different HiperSockets or VLANs within
the same HiperSockets. All security features, like IPSec or IP filtering, are available for
HiperSockets interfaces as they are with other TCP/IP network interfaces.
_ HiperSockets looks like any other TCP/IP interface; therefore, it is transparent to
applications and supported operating systems.
_ HiperSockets can also improve TCP/IP communications within a sysplex environment
when the DYNAMICXCF is used (for example, in cases where Sysplex Distributor uses
HiperSockets within the same System z server to transfer IP packets to the target
The HiperSockets device is represented by the IQD channel ID (CHPID) and its associated
subchannel devices. All LPARs that are configured in HCD/IOCP to use the same IQD CHPID
have internal connectivity and, therefore, have the capability to communicate using
Please Note: HiperSockets is transparent to Connect:Direct for z/OS.
17 December 2019