Mitel Deutschland GmbH 68635RFP36U-01 ユーザーズマニュアル
SIP-DECT OM System Manual
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The OMM always verifies the server certificate, therefore following configuration parameters must be set
for this mode: Trusted Certificates
for this mode: Trusted Certificates
If the server verifies the client certificate, additionally Local Certificate and Private Key must be set.
7.31.4 VERIFICATION OF REMOTE CERTIFICATES
When “TLS authentication” is “ON”, a remote certificate is verified by the OMM as follows:
The signature of the certificate is checked with the public key of the signing certificate. The certificate
chain is checked until a Trusted Certificate is found. If self-signed certificate is found which is not trusted,
the verification fails.
chain is checked until a Trusted Certificate is found. If self-signed certificate is found which is not trusted,
the verification fails.
The current time must be in the validity period of the certificate. For this mechanism a correct system
time must be provided (e.g. NTP).
time must be provided (e.g. NTP).
If one or more of these checks fail, the TLS connection will be closed.
Please note:
All certificates are only valid for a limited time given by the issuer. As soon as
the validity is expired no further communication is possible. The certificates must be
replaced before to prevent a breakdown of call services.
replaced before to prevent a breakdown of call services.
When “TLS authentication” is “OFF”, the OMM verifies the remote certificates and logs any failure but the
established TLS connection will not be closed in case of verification failures.
established TLS connection will not be closed in case of verification failures.
IMPORTANT :
To prevent man-in-the-middle attacks we recommend not to disable the
“TLS authentication” in unsecure environments. We recommend setting “TLS
authentication” and “TLS common name validation” to “ON” in any unsecure
environments for the best security.
7.31.5 ADDITIONAL SECURITY CONSIDERATIONS
For highest security requirements there are additional considerations to be taken into account when
enrolling an OpenMobility system.
enrolling an OpenMobility system.
To prevent manipulations during the initial upload of certificates and keys to the OMM completely, this
should be done in a small private network without a physical connection to an insecure network.
should be done in a small private network without a physical connection to an insecure network.
IMPORTANT :
To prevent manipulation of certificates and keys in unsecure
environments we recommend not to use the automatic import of certificates and
keys. Especially the unsecure protocols TFTP, FTP and HTTP must be avoided. It is
also recommended to protect the selected protocol with a login to prevent
unauthorized access to the private key file.
Furthermore, it is important that the root and administrator passwords of the OpenMobility system are
safe, because with these passwords an attacker could change the configuration to manipulate the
system in various ways.
safe, because with these passwords an attacker could change the configuration to manipulate the
system in various ways.
Although all keys and certificates in the database are encrypted, an automated database backup or
download could be a security leak if the network, transport protocol or servers used are not protected
against manipulations.
download could be a security leak if the network, transport protocol or servers used are not protected
against manipulations.