Nat Traversal - Axis C1004-E User Manual

AXIS C1004-E Network Cabinet Speaker
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Private Branch Exchange (PBX)
When you make SIP calls outside your local IP network, a Private Branch Exchange (PBX) can act as a central hub. The main
component of a PBX is a SIP server, which is also referred to as a SIP proxy or a registrar. A PBX works like a traditional switchboard,
showing the client's current status and allowing for example call transfers, voicemail, and redirections.
The PBX SIP server can be set up as a local entity or offsite. It can be hosted on an intranet or by a third party provider. When you
make SIP calls between networks, calls are routed through a set of PBXs, that query the location of the SIP address to be reached.
Each SIP user agent registers with the PBX, and can then reach the others by dialing the correct extension. A typical SIP address in
this case would be sip:<user>@<domain> or sip:<user>@<registrar-ip>. The SIP address is independent of its IP
address and the PBX makes the device accessible as long as it is registered to the PBX.
Example
sip:myspeaker@company.com
sip:myspeaker@company.com

NAT traversal

Use NAT (Network Address Translation) traversal when the Axis device is located on an private network (LAN) and you want to
access it from outside of that network.
Note
The router must support NAT traversal and UPnP®.
Each NAT traversal protocol can be used separately or in different combinations depending on the network environment.
• ICE The ICE Interactive Connectivity Establishment) protocol increases the chances of finding the most efficient path to
successful communication between peer devices. If you also enable STUN and TURN, you improve the ICE protocol's
chances.
• STUN - STUN (Session Traversal Utilities for NAT) is a client-server network protocol that lets the Axis device determine if
it is located behind a NAT or firewall, and if so obtain the mapped public IP address and port number allocated for
connections to remote hosts. Enter the STUN server address, for example, an IP address.
• TURN - TURN (Traversal Using Relays around NAT) is a protocol that lets a device behind a NAT router or firewall receive
incoming data from other hosts over TCP or UDP. Enter TURN server address and the login information.
PBX
sip.company.com
SIP
SIP
15
sip:office@company.com
SIP