3Com S7906E Command Reference Manual page 730

If no RIP version is specified for the interface and the global version is RIPv1, the interface inherits
RIPv1, and it can send RIPv1 broadcasts, and receive RIPv1 broadcasts and unicasts.
If no RIP version is specified for the interface and the global version is RIPv2, the interface
operates in the RIPv2 muticast mode, and it can send RIPv2 multicasts, and receive RIPv2
broadcasts, multicasts and unicasts.
Examples
# Specify RIPv2 as the global RIP version.
<Sysname> system-view
[Sysname] rip 100
[Sysname-rip-100] version 2
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