Benefits of the SMC-R protocol solution

This information highlights some benefits of Shared Memory Communications over RDMA (SMC-R).

SMC-R protocol solution offers many advantages:

The SMC-R network administration model is similar to the current Transmission Control Protocol/Internet Protocol (TCP/IP) network administration. The SMC-R network administration model is built on a TCP/IP network administration model. By using the SMC-R model, the AIX® operating systems provide a similar network administration model for TCP/IP communications. For example, the TCP/IP model uses the existing IP topology and IP addressing to identify the logical partitions within the network and the Domain Name System (DNS) resources are not changed (host names to IP addresses).
SMC-R protocol solution provides transparency of its usage. It means that all applications and middleware that run on the SMC-R enabled operating systems within the same subnet automatically gain the performance benefits of the SMC-R protocol solution. You do not need to modify the applications to derive value for use the SMC-R protocol solution.
The performance of the transactional and streaming workloads can be improved by using the SMC-R protocol solution. By using the SMC-R protocol solution, transactional workloads can increase its overall transaction rate (that is, transactions per second). This saves CPU resources. Streaming workloads such as File Transfer Protocol (FTP) can save CPU resources and improve its throughput.

Notes:

For short-lived TCP connections, the SMC-R protocol solution is not preferred.
When you use the SMC-R protocol solution, both TCP end points must be located in the same Layer 2 network (same subnet). Therefore, the IP address of the server must be in the same IP subnet (or prefix if IPv6) as the IP address of the client. These conditions are required because the SMC-R protocol solution is not routable.
The implementation of the SMC-R protocol solution on the AIX operating system fully supports VLAN aware mode.