Download Documentation version 1.0 - Linux-Call-Router

To send an email whenever a message is received, give the email address using the
“vbox_email” keyword within the extension’s config file:
vbox_email
[email protected]
It is also possible to attach the recorded audio file:
vbox_email_file yes
This will only work if “sendmail” package is installed. Also it must be configured correctly.
Some mail accounts may recognize your dial-in-IP-address as a spammer’s address, so mail
should be forwarded by your “sendmail” to your provider’s email server. I cannot explain
here how to setup “sendmail”. Please visit www.sendmail.org for further info.
5.13 Encryption
Encrypted Calls
Just pick up the phone and call somebody who uses also LCR, press a key and the call will be
encrypted. - It's easy isn't it?
There are two types of encryption, that can be selected:
•
•
pre-shared keying
automatic key exchange
Both have advantages and disadvantages. Pre-shared keying requires a key to be shared. It is
essential that nobody can eavesdrop the key when it is exchanged. The best way to exchange a
key is to meet the other party. Always note that if the key gets stolen before and even after the
call, the call can easily be decrypted in the future. If you use automatic key exchange, the key
will be erased whenever the call has been disconnected. Also you don't need to share the key
before you make a call. The key exchange procedure does this for you. To be sure, that no
man-in-the-middle modifies the keys, the telephone’s display facility is required. To exchange
an encrypted session key, RSA is used, but this may take some seconds up to calculate the
keys.
Preshared keying
Preshared keying requires some security about handling of the keys:
•
•
•
•
•
The key must be good random.
The key should not be given to other parties (group of people)
The key must be stored secure.
The key can be used in the future to decrypt encrypted calls.
The key must be exchanged in a secure way.
Both parties must be identified by the caller ID or dialed number. In order to select the correct
key, the caller must transmit her caller ID or the called party will not know what key to select.
The
keys
are
stored
in
the
extension's
directory
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