I think ultimately you would want something along the lines of this picture:

http://blog.myitdepartment.net/wp-content/uploads/2009/11/Call-Setup-Example-sipXecs-through-ITSP1.pdf

<http://blog.myitdepartment.net/wp-content/uploads/2009/11/Call-Setup-Example-sipXecs-through-ITSP1.pdf>If
your ISP sends you a static IP address and you can bridge your modem so the
public IP address is sent to a firewall, you can easily have this
environment which works, and works VERY well.

Should you get excessive dos sip invites, you can simply block them at the
firewall with a filter...

It is doubtful your modem will do the type of nat traversal needed for a
successful rollout for trunking or remote users, so this would be the far
simplest approach.

On Sun, May 9, 2010 at 7:53 AM, Tony Graziano
<[email protected]>wrote:

> Didn't mean to answer that twice. Couldn't get BB to send, so went to pc.
>
> ============================
> Tony Graziano, Manager
> Telephone: 434.984.8430
> Fax: 434.984.8431
>
> Email: [email protected]
>
> LAN/Telephony/Security and Control Systems Helpdesk:
> Telephone: 434.984.8426
> Fax: 434.984.8427
>
> Helpdesk Contract Customers:
> http://www.myitdepartment.net/gethelp/
>
> ----- Original Message -----
> From: Tony Graziano <[email protected]>
> To: [email protected] <[email protected]>
> Cc: [email protected] <[email protected]>
> Sent: Sun May 09 07:09:10 2010
> Subject: Re: [sipx-users] Basic deployment scenario - local DNS server
> mandatory?
>
> Rtp is not established until after legitimacy has been determined. I can
> send illegitimate invites forever to port 5060 as a dos attack. An alg
> would
> still pass this through to whatever proxy you use, so the alg is useless as
> a means to protect against it.
>
> The sipx proxy has permissions that require credentials to process an
> outbound call.  Inbound calls should always be allowed, because that IS the
> nature of SIP.
>
> Carriers may wish to deploy using a different sbc. SiPx was designed with
> enterprises in mind, not carriers.
> ============================
> Tony Graziano, Manager
> Telephone: 434.984.8430
> Fax: 434.984.8431
>
> Email: [email protected]
>
> LAN/Telephony/Security and Control Systems Helpdesk:
> Telephone: 434.984.8426
> Fax: 434.984.8427
>
> Helpdesk Contract Customers:
> http://www.myitdepartment.net/gethelp/
>
> ----- Original Message -----
> From: Robert Hoffmann <[email protected]>
> To: Tony Graziano <[email protected]>
> Cc: sipx-users <[email protected]>
> Sent: Sun May 09 05:35:18 2010
> Subject: Re: [sipx-users] Basic deployment scenario - local DNS server
> mandatory?
>
> > It (ALG) gets in the way of sipx in trying to negotiate the sip
> > registration
> > or media.
> >
> >
> I am a little confused now - when I started gathering info on SIP PBX
> deployment an ALG / B2B-UA made sense for me as a means of only opening as
> few inbound / outbound ports as possible (which is a good thing, right?).
> My
> ALG would basically work as a SBC that acts like a virtual endpoint for
> incoming calls, effectively protecting sipX from getting swamped with
> illegitimate RTP streams (i.e. a DOS attack) because the ALG only opens the
> ports negotiated in the SDP. If I got you right - please correct me here -
> you suggest that the typical approach for deploying sipX is more or less
> exposing it with 1001 port forwardings (SIP 5060 + RTP 30000 - 31000) and
> no
> outbound port firewall rules (as any destination port number may be needed
> for SIP signaling or RTP streams). Would you really do that in a
> professional environment? This may sound like criticism but the truth is
> that I have absolutely no clue. :-) Please enlighten me!
>
>
> > Leaving it on will result in broken media for remote users as well as any
> > itsp calls.  It is a big fat no-no.
> >
> >
> How would a SIP carrier use sipX if it were incompatible to SBCs due to the
> fact that you cannot "dumb it down" ? Maybe I did not understand the scope
> /
> goal of sipX?
>
_______________________________________________
sipx-users mailing list [email protected]
List Archive: http://list.sipfoundry.org/archive/sipx-users
Unsubscribe: http://list.sipfoundry.org/mailman/listinfo/sipx-users
sipXecs IP PBX -- http://www.sipfoundry.org/

Reply via email to