https://community.cisco.com/t5/network-security/how-firewall-pinholing-works-for-sip/m-p/2482289#M238488 <P>i would like to understand how pinholing works on Cisco Firewalls. I am from teleresence background.<BR />We use SIP as a protocol to make video calls. i have read about problems which sip has traversing NAT.<BR />protocols like h460 17/18/19 are used to fix this issue.<BR />As per my understanding &gt; any thing from private to public is allowed.</P><P>so suppose a user A Video endpoint dials user B Video End point on public internet.<BR />how will a pinhole for signaling and media will be created.<BR />Also what happnes if user B shares presentation and traffic comes from public to private network.<BR />how does a firewall takes care of that.</P><P>Please help me understand on layman terms.</P><P>Thank you in advance.</P><P>&nbsp;</P> Tue, 12 Mar 2019 04:11:54 GMT videoconfrencing1944 2019-03-12T04:11:54Z https://community.cisco.com/t5/network-security/how-firewall-pinholing-works-for-sip/m-p/2482289#M238488 <P>i would like to understand how pinholing works on Cisco Firewalls. I am from teleresence background.<BR />We use SIP as a protocol to make video calls. i have read about problems which sip has traversing NAT.<BR />protocols like h460 17/18/19 are used to fix this issue.<BR />As per my understanding &gt; any thing from private to public is allowed.</P><P>so suppose a user A Video endpoint dials user B Video End point on public internet.<BR />how will a pinhole for signaling and media will be created.<BR />Also what happnes if user B shares presentation and traffic comes from public to private network.<BR />how does a firewall takes care of that.</P><P>Please help me understand on layman terms.</P><P>Thank you in advance.</P><P>&nbsp;</P> Tue, 12 Mar 2019 04:11:54 GMT https://community.cisco.com/t5/network-security/how-firewall-pinholing-works-for-sip/m-p/2482289#M238488 videoconfrencing1944 2019-03-12T04:11:54Z