http://kb.juniper.net/InfoCenter/index?page=content&id=KB19913&smlogin=true
SUMMARY:
What is the difference between SRX-MP-1SFP and SRX-MP-1SFP-GE mPIMs which are both 1-port SFP GE mPIMs for SRX2xx platforms?
PROBLEM OR GOAL:
This applies to the following models / part numbers.
SRX-MP-1SFP / 750-029145
SRX-MP-1SFP-GE / 750-032730
SRX mPIMs are applicable to the following platforms.
SRX210
SRX220
SRX240
CAUSE:
SOLUTION:
The SRX-MP-1SFP-GE is a newer model meant to replace the original SRX-MP-1SFP mPIMs. Both can support same SFP optic modules. Below are some of the differences between the two models.
SRX-MP-1SFP
Supported since JUNOS 9.5
Supported on SRX210 and SRX240, not supported on SRX220
Cannot be used as member of reth interface in a chassis cluster
No jumbo frame support
Limited to 100Mbps due to port connection to backplane limitation
Cannot be used for fabric link in a chassis cluster
SRX-MP-1SFP-GE
Supported since JUNOS 10.4
Supported on SRX210, SRX220 and SRX240
Can be used as member of reth interface in a Chassis Cluster
Supports jumbo frames up to MTU 9010 bytes
GE backplane connection to allow near 1GB line rate
For SRX Series Chassis Clusters made up of SRX100, SRX210, SRX220,
SRX240, or SRX650 devices, SFP interfaces on Mini-PIMs cannot be used
as the fabric link. This functionality will be supported starting with Junos 11.4R1 and onwards.
Wow okay so even the High-Perf SFP won't even do full GB due to backplane limits.