VoIP - Totally confused
Hi to all,
I am quite confused because I have asked the support department to help me to protect our VoIP system at home.
The first agent told me that the FortiGate can not protect against SPAM calls and that the best approach is "to disable SIP ALG on the FortiGate, as it may interfere with VoIP signaling and is not required in most modern deployments".
Then, the ticket went to another agent (I do not know why) and this one told me the following: "Please note that, to protect your VoIP services, the best approach is to use the Fortigate SIP ALG inspection feature". in addition: "With the above configuration, you will not have ghost calls nor unwanted call forwarding nor spam calls".
So, one says Yes SPAM and No SIP ALG and the other one, the opposite: No SPAM and Yes SIP ALG.
The second agent asked me to run the following:
1. Delete the SIP Session-Helper:
config system session-helper
delete 13
end
2. Set the ‘default-voip-alg-mode’ to ‘proxy-based’:
config system settings
set default-voip-alg-mode proxy-based
end
3. Enable the SIP ALG VoIP profile:
config voip profile
edit default
config sip
set status enable
set rtp enable
set strict-register
enable
end
end
4. Clear all existing SIP sessions:
diagnose sys session filter clear
diagnose sys session filter dport 5060
diagnose sys session clear
diagnose sys session filter clear
diagnose sys session filter sport 5060
diagnose sys session clear
5. Confirm that new SIP sessions are using SIP ALG inspection (sessions should have the tag ’helper=20’)
diagnose sys session filter clear
diagnose sys session filter dport 5060
diagnose sys session list | grep helper
diagnose sys session filter clear
diagnose sys session filter sport 5060
diagnose sys session list | grep helper
So, I am so confused that I am worried about the codes I have ran in CLI because I do not know what I am doing. So, please, could you be so kind as to let me know which approach is the correct one and if the codes I have ran could mean a vulnerability in our network? And is the FortiGate able to protect against SPAM calls?
Thank you very much.