In scenario E, the complete installation consists only of one server with cFolders installed on ECC.
SAP generally recommends variant E only for internal collaboration with cFolders 4.00, as both cFolders 4.00 and ECC 6.00 are situated in the intranet.
Access to cFolders by external users in this scenario would result in access to the intranet by external users.
However, placing the whole system (ECC 6.00 with cFolders 4.00 on top) into the inner DMZ would enable - for access from the extranet - a higher level of security than allowing extranet access to a system (ECC 6.00 with cFolders 4.00 on top) in the intranet.
For more information, see the SAP NetWeaver Security Guide, section “Using Multiple Network Zones” on the SAP Help Portal at help.sap.com under SAP NetWeaver → SAP NetWeaver 2004s SPS 07 → English → SAP NetWeaver Library → Administrator’s Guide → SAP NetWeaver Security Guide → Network and Communication Security → Using Firewall Systems for Access Control → Using Multiple Network Zones.
SAP Consulting can offer billable support for risk evaluation.