Tuning network utilization is a complex and sometimes very difficult task. You need to know how applications communicate and how the network protocols work on AIX and other systems involved in the communication. The only general recommendation for network tuning is that Interface Specific Network Options (ISNO) should be used and buffer utilization should be monitored. Some basic network tunables for improving throughput can be found in Table 2-2 on page 53. Note that with network tuning, indiscriminately using buffers that are too large can reduce performance.
For more information about how the different protocols work, refer to: