No one echo?
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Since I travel a ton I just upgrade to the new 4g Novatel mifi and fast there's no doubt about that. however soon as I change networks my sip phone fails to connect . does anyone else have this problem? Is this a known issue?
thanks
ym
No one echo?
Don't be quick to assume that Verizon is deliberatly blocking Sip traffic there are other factors to consider.
The Most important for now being the network performance. SIP and other voip protocols are demanding and need a stable connection or else they might function poorly or not at all.
To test the speed of the connection the most common way is to visit a website such as speedtest.net and also using their sister site pingtest.net.
Don't forget to also use cmd and ping the IP or hostname of the sip server several times and take note of the ping times.
If my suspicions are correct it may in fact be a timeout caused by high ping times.
I have been testing this all day. It works fine on my old Novatel (same manufacturer) USB Modem but not on the MiFi 4G device. I am going to activate my old 3G device later tonight to see if that works. I have tested the bandwidth and verified this with the Softphone provider which they confirmed but they are not able to help me with anything else. The MiFi device has very limited settings and does not give you the ability to make certain router changes that are prescribed by the VOIP provider.
You could try running SIP/RTP through a VPN. Alternatively, some SIP providers offer service on alternate ports to get around blocking.
"I didn't get fat by accident. This was a personal choice. " - Kevin Gillespie
I thought they were blocking sip too. I have a feeling it is more of a nat problem. I tried using blink on my computer and setting up a vpn at home using a linksys router and dd-wrt. When I am vpn'd in it works like a champ. Audio quality is wonderful. Not a perfect solution, but it seems to work.
Dan
They are definitely blocking SIP, no question about it!
They must be doing some deep packet inspection as well, because if I try and send some random UDP traffic to port 5060, the packet simply doesn't arrive, but if I send a valid SIP REGISTER command to a SIP server, I get a packet back with a 500 Internal Server error. The packet looks like it's coming from the SIP server (both from the source IP in the IP header and the source IPs specified in the SIP payload itself), it's a valid SIP packet, but I'm not so sure it actually is coming from the SIP server, I'm speculating that it's coming back directly from Verizon, who's spoofing as the destination. I could confirm this by doing some further testing, but I don't think it help in any way.
Here are the facts:
- They definitely block random data sent to UDP port 5060 (and they don't block the same random data sent to UDP/5061 on the same destination).
- Interacting with multiple SIP servers when routed over Verizon's wireless network (through the MiFi) yields to REGISTER errors and dropped INVITEs, but routing the exact same traffic over different links works perfectly, and furthermore, routing the traffic over a VPN that's running over the Verizon wireless network also works! The only time it doesn't work, is when it's routed over Verizon wireless directly. The VPN route is not only at least as slow as the network it's riding over, the traffic has to go over an extra hop, get NAT'ed one extra time, etc... hence it's latency is higher and it's NAT profile is even worse. Yet it, it works perfectly.
There's no question, they are blocking SIP, and from the FCC's Net Neutrality rules's summary:
"mobile broadband providers may not block lawful websites, or block applications that compete with their voice or video telephony services."
Hence they are violating the new Net Neutrality rules...
Obviously, my solution it so simply route all SIP traffic over a VPN connection. In fact, some VoIP providers offer their own VPN services for these types of reasons.
This is a real bummer. Man, we need to get them on the record for this one...
--Kidd
Hear me on Twitter: @alexkidd1 / On YouTube: @AlexKidd4Fun
On the day 4G LTE launched in my market (Las Vegas, NV) I picked the LG USB modem, and later changed to the Pantech USB modem, and both supported SIP and other RTP streams (i.e. Video) just fine.
Today, in preparation for a system demo at a location that doesn't have public WiFi available, I went to a Verizon Wireless "corporate" store, and they provided me with a Samsung SCH-LC11, and upgraded my 4G line to this device. When I got back to the office to test SIP calls, in my logs I received a 500 Server Internal Error
Warning: 399 sipalg "Internal Error".
After calling the Verizon Wireless store, they told me this is an "older device", and I should have received the one that just launched. Went back to the store, but was told the store couldn't sell me the "new device", the Novatel MiFi 4620L, since it wasn't "officially launched" in Verizon stores until April 12th 2012.
The tech at the store noticed that Best Buy had an "early release", and started selling the "new device" on March 26th.
They returned and restocked the "old device", and sent me over to Best Buy.
...I'll skip the part of the story that details my painful (but ultimately successful) experience at Best Buy Mobile, and just say that I walked out of the store with a new, activated Novatel MiFi 4620L.
When I got back to the office to test SIP calls again with the "new device", in my logs I received a 500 Server Internal Error Warning: 399 sipalg "Internal Error". Exactly the same error.
I assumed (incorrectly) that SIP ALG would have been corrected on the "new device", but proved that the latest MiFi device also throws the same errors as the old device.
Just my 2 cents, but as I know a fair amount about Verizon Wireless' network, I can assert it's NOT them causing the SIP errors, but rather it's the device manufacturer, by turning on SIP ALG on the router part of each MiFi device, and NOT allowing the customer to turn this off in settings.
Now, it's entirely possible that Verizon Wireless has "instructed" the manufacturer(s) to screw up any SIP based communication, but I just can't see the value proposition in blocking SIP on their network... and, if they WERE blocking ALL SIP, then my USB modem wouldn't work either.
All I can say is.... Aaaaaaargh!
GG
Interestingly enough, I WAS able to get connected to VoIP services by running on a port OTHER than 5060 (well known SIP port)... I changed to 5080 and voila, I was able to connect, make calls, etc. without the device ruining my day.
RedHeadTwink "plug the mifi into the computer via usb and see if that helps."
I set the device to USB Tethered mode in the settings, but when I tried to plug in via USB, it couldn't find any drivers... after searching the internet, I STILL couldn't find any drivers, so couldn't test this fully.
...bottom line, I think this thing is going back to the store.
GG
I can now confirm the issues related to SIP is device specific. We were trying the service with the new Verizon Wireless Novatel MiFi 4620 4G LTE wireless access point.
I have certified other 4G LTE devices on the Verizon network, but the device I mentioned above has all kinds of issues we've noted:
1.) SIP ALG is enabled on all traffic on destined for port 5060, which breaks SIP completely. Changing to 5080 or another port does allow SIP traffic, and allows us to create 1 call.
2.) There are other packet "manipulations" that occur with the built-in router on the device that break other SIP traffic, especially in the tear down, and also with multiple RTP streams, i.e. 2 or more calls.
USB Tethered mode is not a "modem only" interface (as it is with the Pantech UML290), rather it performs the same routing that occurs when connected via Wifi... which is broken for SIP.
Basically, the device is non-operable with SIP at this time, although it will allow basic "emergency" SIP... just not all features.
Anyone who is wanting to upgrade from the Novatel 4510 to the 4620 should probably wait until there is a new driver/firmware package (at least), then re-test.
Thanks for your continued testing. I'm relieved to hear that the SIP limitations are at least confined to specific devices and therefore finger can be pointed to a manufacturer. EDIT: I see that you have found some LTE devices that do work with SIP. Hopefully with your bug reports, this Novatel model can be fixed with a firmware update.
--Kidd
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