atcomsystems.ca/forum Forums TDM Business Telephone Systems Comdial Telephones & Systems Offsite EP200/300 without VPN

ooops apparently someone didn't read the remote configuration guidelines :x
Depending on your application it may or may not hurt your pocket book to bad.

Thanks for all the input! So far it appears that no one has succussfully deployed any remote phones without VPN tunneling. Not what I had hoped for but--maybe I'll have to do some more testing on my own such as port scanning to dissect the protocols.
Has anyone tried giving the Sip Server Blade a Public IP? Obviously this would create a routing problem for SIP endpoints on the private network, but not a problem is all sip phones are off site.
Here's where Tadiran has everyone beat with their Sentinal. It's acts as a proxy to bridge the gap between the public & private networks.

Just another thought! If we can get these phones to work without a VPN than we can also get them to register on a call controller other than Comdial. For example; if I'm at home with my EP300 I would have a choice of 1) register to the Comdial MP5000 in the corporate office & use their PSTN to place a call or 2) register to nexvortex etc & place a SIP call using their PSTN rates. Thus selecting the location that I want my PSTN call to originate from & saving on toll.

Here are my findings:

Local Host:
Port 23(TCP)
Port 5060(TCP)
Port 4340(UDP)

Remote Connections:
Hyperterm consistently uses TCP port 17xx
VMMI consistently uses TCP port 18xx
EP200 consistently uses UDP port 161xx

Hope this helps

[This message has been edited by Jatkins (edited April 12, 2005).]

[This message has been edited by Jatkins (edited April 12, 2005).]

Hey Guys,

If you ask 10 people at Comdial how to remotely connect an EP200/300 via the Internet, you will receive 10 different answers. Comdial is not hiding information; the people you are asking the question to at Comdial does not know the answer.

Here are the facts:

SIP is not “NAT friendly” meaning it will not work across the internet unless all enpoints (EP200/EP300) and the SIP server (MP1000/5000) have a public IP address.
You can not port forward ports like you can with VoIP networking and iPrimo because the private IP address does not get translated. For example, let’s say your EP300 has an internal IP address of 192.168.1.101 and your public IP address is 12.153.69.2, port-forwarding 5060 to the private IP address 192.168.1.101 (EP300) will not do you any good because once the packet is forward to the private IP address, it looks into the payload of the packet that has the “un-translated” private IP address, incidentally is not routable over the Internet. This like I call you from a hotel room and leave you a message at your home to call me back at ext 1001 rather than the PSTN number.

There are to ways you can have the EP200/300 work across the Internet/NAT:

1) using a VPN
2) use SIP aware firewall/router

A SIP aware firewall/router looks into the payload of the packet and does the translation so it can work behind NAT.


I believe this was an oversight on Comdial’s part because competitors have this “translator” built into their gear.

BV

Hey BV- good to hear your input. Hope North Carolina is to your liking.

Loving NC, thanks for asking. I made the move just in time before the layoff.

Good luck. You've always been the source I trusted for info. If you get some spare time email and keep in touch with what you are doing. Dave T.

Will Do. I won’t be a stranger like my last departure. This time Comdial beat me to the punch. At least I’m in an area (RTP) that has more technology jobs than southwest Florida.

BV

Be very careful of another telecom company that has a major group in RTP. I sell that product also and am hearing some disturbing possible news.