1-12
MSCA (Multi-Service Card A) is back main control board of MSR 50 series to carry various service
modules.
ESM module
Installed on MSCA, ESM module supports IPSec and by using hardware encryption expedites IP packet
encryption. The use of hardware encryption/decryption and hashing operation allows the router to
encrypt packets with high performance and reliability.
The encryption card is optional. On a router installed with an encryption card, the main control board
functions to route IP packets and implement encryption-enabled VPN, while the encryption card
functions to encrypt packets.
Table 1-12
Encryption card attributes
Attribute
Description
Protocol IPSec
Hardware encryption algorithm
Key algorithms: DES, 3DES, AES
Authentication algorithms: HMAC-MD5-96, HMAC-SHA-1-96
VPM and VCPM modules
VPM (Voice Processing Module) functions to coding/decoding, EC and CNG of voices.
VCPM (Voice Co-Processing Module) processes the voice data together with VPM.
PSU
Functions
The power supply system of the MSR 50 series can work in either single-power or dual-power mode. In
dual-power mode, the two PSUs (DC-input or AC-input) function in redundancy backup mode. That
means, when a PSU fails or its power supply is disconnected, another PSU can still work and supply all
the power required by the system.