Ultra Secure Mode
Polycom, Inc. 881
Media Encryption and Authentication
In compliance with UC_APL_SEC_0013, the RMX supports the Privacy Protocols:
● AES_CM_128_HMAC_SHA1_32
● AES_CM_128_HMAC_SHA1_80
System Flags
The Privacy Protocol selection is controlled by the SRTP_SRTCP_HMAC_SHA_LENGH System Flag. To
modify its setting, manually add it to system.cfg and set its value as summarized in the table below.
Range: 80, 32, 80_32
Default: 80
Dial-in / Dial-out Connections
For dial-out and dial-in connections to and from SIP Clients, BFCP/UDP or BFCP/TCP protocol can be given
priority by adding the adding the SIP_BFCP_DIAL_OUT_MODE and SIP_BFCP_DIAL_IN_MODE System
Flag to system.cfg and setting their values to UDP, TCP or AUTO.
The Collaboration Server’s content sharing, as determined by the system flags settings and SIP client
capabilities, is summarized in the following table:
Privacy Protocols - Flag Settings
SRTP_SRTCP_HMAC_SHA_LE
NGH Flag Value
Negotiation Protocol
SDP
Authentication Tag Length
RTP RTCP
80 AES_CM_128_HMAC_SHA1_80 80 80
32 AES_CM_128_HMAC_SHA1_32 32 80
80_32 First:
AES_CM_128_HMAC_SHA1_32
Second:
AES_CM_128_HMAC_SHA1_80
32 or 80
(Depending on
negotiation
result)
80