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KubuliJohn's profile

New Member

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2 Messages

Wednesday, June 7th, 2017 9:00 AM

Port Redirection on Cisco DPC3941B

Does anyone know how to redirect incoming ports to a different internal port?  The Port Forwarding configuration screen on this modem only lets me forward incoming packets to the same port on a different internal IP.  Port Triggering seems promising, allowing me to specify a trigger port and a target port but it doesn't have any IP address information in it.  Am I supposed to combine a port forwarding rule with a port trigger based on the service name?

 

Thx in advance!

Accepted Solution

Gold Problem solver

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575 Messages

8 years ago

Hello KubuliJohn,

 

I apologize but the model of Cisco business gateway you are using may not supply the dynamic features that a privately owned router could provide. Based on what was discussed if this page does not supply the needed features you may want to consider 3-party equipment. I does this answer your question?

Gold Problem solver

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575 Messages

8 years ago

Hello KubuliJohn and welcome to forums,

 

Sorry for the delayed response to your post. Depending on the model of modem and the exact function of the forwarding/triggering would determine the need of using either or both features. With port triggering for our Business Gateways, this feature monitors outbound traffic on your network. When traffic is detected on a particular outbound port, the Gateway remembers that computer's IP address, triggers the inbound port to accept the incoming traffic, and directs the communications to the same computer. With port forwarding inbound connections are to be forwarded to a specific machine on the internal network. Port forwarding will only work if the local machine that they want traffic forwarded to is assigned an IP address in one of the private IP subnets. To re-cap, depending on the function of your communication would determine your need or use of these features. I hope this information helps you configure your modem. Please post back or message me if you have further questions.

 

Thank You

New Member

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2 Messages

8 years ago

Hey Michael:

 

Thanks for the reply.  The modem we have is a Cisco DPC3941B.  I am attaching a screenshot of the Port Forwarding configuration screen on the modem admin page.  For specifying the ports there is only the start and end of the range to forward, no "port translation" (i.e. forward incoming requests on port 8080 to 10.1.10.15:80).  Is this possible on this model of Cisco router?

 

John H.

 

Screen Shot 2017-06-12 at 12.38.14 PM.png

New Contributor

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11 Messages

7 years ago

Wow.  I've never seen any router that didn't provide this functionality.  Like how the heck are we supposd to open the same service on multiple hosts?  In this case specifically I want to RDP to a few different PCS.  But unless I hack the registry on the PC to chang the RDP listerner port (not a trivial task), then I'm limited to the one PC in the 'port forwarding' setup....

 

Between this and all the other problems and drawbacks, i am proclaiming comcast business a bust.  Looking for alternatives.  

Visitor

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3 Messages

7 years ago

Were it me I wouldn't have and port open for RDP to the interent. Better to VPN in and RDP through the tunnel.

Contributor

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19 Messages

7 years ago

The router is faulty and being recalled.