access to NAS blocked on verizon wireless

[kevincw02]

I have an app to access my home NAS so I can view important docs while traveling.  The app is called DSFile for synology.  It's been working for 6 months and suddenly stopped working.  It works when I'm on a wifi connection and when I'm connected to a vpn on my phone (over 4g or 3g).  But if I'm just on 4G or 3G, the app doesn't work.  It's obvious to me that verizon is blocking it and I'm not sure how to correct it.  The idea of trying to explain this to a first level verizon customer service rep is daunting.  I have tried changing the port on my NAS but it doesn't matter.  Verizon appears to be doing layer 3 filtering.  Any ideas?

[Ann154]

I think you might have some knowledge on this.

To the OP, are you try to remove access a network on your phone? Which phone do you have? Have you tried contacting the developer of the application?

[vzw_customer_support]

Hello Kevincw02,

I appreciate you bringing this concern to our attention. I want to ensure that were able to come to customized solution here for you. I do have a few questions for you. Did this application recently receive an update? What device are we working with?

YosefT_VZW
Follow us on Twitter @VZWSupport

[John_Getzke]

Thanks for the shout out Ann,

Kevin, I can tell you right now that based on your description VZW is almost certainly blocking your traffic.  We see problems like this all the time in the MiFi forums where folks are trying to remote connect to home servers, IP cameras or host XBox games.

Simple truth is that VZW's NAT firewall overrides any customization settings that the devices have.  It doesnt matter how you configure your device or what custom ports you setup.  As soon as that traffic hits VZW's network you are at the NATs mercy.  It wont take you long to figure out what is allowed and what is not, and as you can guess only very common ports are opened and allowed through.   

VZW will not make exceptions for you in this area.  Your choices are as follows:

1. Maintain a VPN, as you have already mentioned

2. Purchase a Static IP Address from VZW for a few hundered dollars

3. Configure your device to connect over 3G Only (EVDO), the old network does not have these restrictions

4. Switch Service Providers

Let me know if you need more info.

[kevincw02]

@Ann154 I am not trying to remove any access.  I have a samsung galaxy nexus.  The problem is not device or application specific -- I can tether the phone to a computer and use another PC program to try to use webdav (http/https) and it is blocked.

[kevincw02]

No, this application did not recently receive an update.  I am using a Samsung galaxy nexus.  

[kevincw02]

This solution was working, over 4G, for the last 4-6 months without issue -- somthing changed.  The problem happens when I force the phone to 3G as well.  webdav which uses http/https transport is fairly common and the firewall should see it as "normal" web traffic.   I think somthing else is going on here.

[Ann154]

Sorry the keyboard wrote it wrong. I was trying to ask if you were access a network remotely.

[John_Getzke]

Ah OK, didnt know that info from before.  Since you application is trying to send everything over HTTP or HTTPS then the firewall would not be a problem, not to mention it was working before.

I do not have specific experience with DSFile or WebDAV so forgive my ignroance.  My research shows that WebDAV is a "set of extensions to the HTTP protocol" so I'm not quite sure if works the way I think it does.  I'll see if I can dig up any other details that can assist us.

Can you app be accessed over a different VZW device?  Perhaps stopping in at a VZW store when you have a chance to borrow one of thier devices could serve as confirmation of a network limitation or a device limitation. 

[kevincw02]

@ann154 not a network per se.  This is just a device on the public internet serving the webdav protocol (based on http).  It's strange that verizon would block it since it was working before and doesn't necessarily take up a lot of bandwidth.  I imagine I use more bandwidth in youtube and pandora in a day than webdav in 1 month.