Toshiba ID EDGE, Описание

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Networking
Remote IP Telephones
IPedge General Description 01/12
45
Remote IP Telephones
Benefits
• Small office or Home office users can be connected to their work phone system.
• When using SoftIPT, enables Road warrior scenarios.
Requirements
In order to connect a remote IP telephone (or SoftIPT) to an IP edge node, either of the following
mechanisms can be used:
Media Relay Server (MRS) – Within the Firewall and the NAT router at the main office, the
following ports need to be opened and forwarded; in order for the remote IP telephone to
communicate to the IP
edge system:
• H.225 – UDP (1718 – 1719)
• Megaco – TCP 2944
• Media Relay Server – UDP port range (21000 - 22999)
• FTP, FTP Data – TCP ports (20-21)
IPSec VPN – An IPSec VPN session needs to be setup between the remote location and the main
office. In case of a SoftIPT the IPSec VPN connection is established by a soft VPN client back to
the main office.
Interactions
• When using MRS, most home office and small office routers require no configuration in the
firewall and NAT locally as they tend to initiate the connection and save state for the inbound
connection. In some cases this may not work and the ports references in Requirement 1 may
also have to be opened on the home router.
• Using the MRS the IP edge system dynamically and automatically configures port forwarding
rules for any NAT traversal related issues. If, for some reason a remote IP telephone still cannot
register due to local NAT router issues, configure the remote IP telephone’s station
programming to use the Static MRS parameter. This will resolve any NAT issues that prevent
registration of the IP telephone.