18.2.1. Restrictions 
- The CSTA traffic is clear text protocol and should operate in trusted network environment. If not possible use the Integrated VPN Service of the OS4K Platform / Portal - please see OpenScape 4000 V8, Platform Administration (Portal), Administrator Documentation, chapter 2.5 Integrated VPN Service.
- This feature is not compatible with "Signaling and Payload Encryption" in HiPath 4000 V3.0, i.e. encrypted signaling and payload cannot be transmitted in a network with HiPath 4000 V3.0. In a network with HiPath 4000 V3.0, it is not possible to encrypt the trunking path between the two systems. HiPath 4000 V3.0's internal encryption can be activated, however, within HiPath 4000 V3.0.
- If encryption has been activated on an STMI2/NCUI2+ board, the number of configured channels must be 33% less than when encryption is deactivated.
-
For the exact number of B channels, see "Gateways HG 3500 and HG 3575", Section 2.6, “B Channels”.
- Up to 240 HFA and SIP subscribers (native or UFIP) can be configured on the common gateway HG 3500 on STMI4 using SPE.
- Up to 120 HFA subscribers can be configured on STMI2 using SPE.
- SPE is not supported on STMI2 for SIP subscriber functionality (native or UFIP).
- T.38 fax streams are not supported for SPE
Table 86. Payload encryption
|
Feature
|
STMI2
|
STMI4
|
SoftGate/STMIX/STMIY
|
|
Native SIP Trunk
|
 * |
* |
|
|
SIP-Q Trunk
|
|
|
|
|
SIP subscriber - classic
|
 |
|
|
|
SIP subscriber - UFIP
|
|
* |
|
|
Circuit Connectivity (UFIP)
|
|
|
|
|
HFA subscriber
|
** |
|
|
|
H323 Trunk
|
|
|
|
|
* Only signaling encryption supported. SDES is supported on SoftGate/STMIX/STMIY only.
|
|||
|
** Maximum of 120 SPE subscribers supported on STMI2 boards.
|
|||
IMPORTANT:
Starting with V10R0 the support for STMI2 will not be offered anymore. The
replacement for STMI2 is STMIX/STMIY.