Connectrix is the family name for EMC Corporation's range of storage network directors and switches. EMC does not manufacture any of these devices, instead they rebadge several of the market leading brands.
In many cases the EMC version of a switch will have customized EMC firmware, which will improve larger SAN design and/or compatibility between multi-vendor products. These customizations are usually created by the original switch vendor to EMC's requirements.
Read more about Connectrix: Switch Families, OEM Identification