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Building a Personal VoIP System

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Re: Building a Personal VoIP System

#101
post #14

Has someone good experience with a VoIP-Provider (not OVH or Sipgate) in Europe?

Do you have any specific issues with Sipgate? I only have a couple of numbers with them and don't use them much but am curious what their reputation is like.

I can't say anything about sipgate's reputation, as i haven't used their service. It just has been an issue with limited service availability in my country (BE)..

Re: Building a Personal VoIP System

#102
post #16

Earlier quoted context omitted.

Yes, Asterisk can poke holes in NAT on its own just fine. I was surprised how pessimistic the article is on this. I have systems running for months and years behind NAT with no issue. You might have to disable direct media (endpoint/disable_direct_media_on_nat). Also, this is just uptime related tip not NAT, you must explicitly set registration/max_retries to a huge number otherwise Asterisk just gives up permanently…

Are you doing calls to/from other sip URIs that are also behind NAT, or just using your trunk and internal extensions?

Trunk and internal, and I usually put all the phones in their own VLAN w/o direct Internet access. I don’t really see a use for dialing arbitrary SIP URIs. If I need to add a remote phone I’ll just connect it directly with a network tunnel.

Re: Building a Personal VoIP System

#103
post #43

Earlier quoted context omitted.

For what it's worth, and if you're willing to tinker, you can get IPv6 for free through a tunnel as long as your router responds to ICMP: https://tunnelbroker.net/ You can get a bunch of /64s and a /48 for free because HE really wants everyone to have IPv6 available already. Picking the right internet exchange to route from and making Netflix not throw a fit requires some minor experimentation but I've found it to wo…

The SIP provider would also need to support IPv6 for this to do any good. voip.ms does not: https://wiki.voip.ms/article/FAQ#Do_you_Support_IPV6_with_SI...

That's rather silly. Getting IPv6 connectivity is usually the difficult part, and servers are the easiest things to get IPv6 for. I wonder what part of their tech stack is still incompatible after all these years.

Re: Building a Personal VoIP System

#104
post #79

Earlier quoted context omitted.

For what it's worth, and if you're willing to tinker, you can get IPv6 for free through a tunnel as long as your router responds to ICMP: https://tunnelbroker.net/ You can get a bunch of /64s and a /48 for free because HE really wants everyone to have IPv6 available already. Picking the right internet exchange to route from and making Netflix not throw a fit requires some minor experimentation but I've found it to wo…

> You can set up advertisements from any Raspberry Pi or other computer as long as it has outbound connectivity. You mean send the advertisement and do the SIT tunneling on that machine?

Correct! It's relatively straightforward, actually: https://devzone.nordicsemi.com/nordic/nordic-blog/b/blog/pos...

You use one of the /64 tunnels provided for you to route the /48 tunnel to the rest of your network. You advertise a subnet from your /48 to your local network and if you've got SLAAC enabled on your hosts that's all there is to it.

You may need to mess with the default DNS server to get IPv6 results, though, that depends on whether or not your standard DNS server will respond to AAAA requests. It usually should, but some ISPs don't.

This only works for a flat network, of course. If you've got different routers, you'll need to set up a more complicated setup.

Re: Building a Personal VoIP System

#105
post #9

Having gone down this road many times with freepbx, asterisk, etc.. I ultimately settled on just using voip.ms and connecting phones/sip clients directly to their internal sub-accounts with voicemail. They have enough features for most users so you don't need to worry about running your own PBX.

[deleted]

Re: Building a Personal VoIP System

#106
post #78
post #58

Earlier quoted context omitted.

They don't always work... The idea is if you send UDP packets to destination so arranged by middleman(STUN) or to a proxy so arranged by middleman(TURN) as an outgoing traffic, your Wi-Fi should be smart enough to set up a temporary NAT entry to allow responses to reach your $LOCAL_IP:$PORT. In reality, the Wi-Fi may have short memory or may be dying behind a refrigerator covered in dust and not able to handle all ne…

Why would that be more reliable than TURN? If your router "forgets" about established streams half-way, your VPN will not stay connected either.

UDP is unreliable transport by specification, so I guess that if a network equipment such as a router cannot cope with the general workload, it would probably sacrifice UDP first without a second thought.

Re: Building a Personal VoIP System

#107
> SIP was initially released in 1999, and was designed with the assumption that each device has its own globally routable public IP address. After all, the IPv6 standard was released back in 1995, and NAT would soon be a thing of the past…right? Unforunately, this did not end up being the case.

AFAIK, most residential and commercial ISPs these days do assign customers both a dynamically-DHCP-leased IPv4 address, and a static, globally-routable IPv6 prefix — usually a /64, though some are nicer than that. If you put your ISP's gateway router into bridge mode, and then plugged your computer directly into it — then your device would acquire both an IPv4 and an IPv6 address.

But routers — including ISP gateway routers — insist on doing NAT not only for IPv4, but also for IPv6 (using the fe80:: prefix.) So on any regular home or office network, devices are going to acquire private-use IPv4 and IPv6 addresses.

Is there some reason that modern routers don't do NAT for IPv4, while just further splitting+assigning the received prefix for IPv6, such that every device on the network receives a private IPv4 addr, but a public IPv6 prefix, e.g. a /72?

I know that Internet-backbone network switches ignore the last 64 bits of IPv6 in their routing tables; but those bits are still being carried in the IPv6 packets, and once they reach your home router, it can make use of them to route to the final destination (i.e. one of the devices behind it.) Wasn't this supposed to be the idea?

Re: Building a Personal VoIP System

#108

Earlier quoted context omitted.

Same here. 3 businesses, only 1 problem in 10 years. The only thing I have to add: if you need to make telephone calls, the call quality using a SIP phone is much better than using a softphone.

This isn't necessarily true, a computer can speak SIP too, with a good headset it's just as good.

Yeah, I would second this. In SIP a UA is a UA. So long as your softphone is good and your microphone is as well, there shouldn't be any difference. Although I would suspect the general experience may be that people with softphones more often will have terrible microphones for their PC...

Re: Building a Personal VoIP System

#109
post #78
post #58

Earlier quoted context omitted.

They don't always work... The idea is if you send UDP packets to destination so arranged by middleman(STUN) or to a proxy so arranged by middleman(TURN) as an outgoing traffic, your Wi-Fi should be smart enough to set up a temporary NAT entry to allow responses to reach your $LOCAL_IP:$PORT. In reality, the Wi-Fi may have short memory or may be dying behind a refrigerator covered in dust and not able to handle all ne…

Why would that be more reliable than TURN? If your router "forgets" about established streams half-way, your VPN will not stay connected either.

Makes it boolean. It's connected, or it's not. "One of RTP media transports to one of destinations is failing to establish DTLS ciphering and I think it has to do with either RTC issue or Chrome bug" is a self inflicted pain.

Re: Building a Personal VoIP System

#110

Earlier quoted context omitted.

I've been using a voip number for all my sms 2fa needs for the last 5 years while living abroad. I have a dozen banks and other financial institutions plus the irs happily accepting it. Some companies, like openai, wont accept it, for those I just buy single use SMS numbers.

I've had problems with a bunch of places, so it's at least YMMV then. And I'd be wary of transferring an existing number in (as opposed to getting a new voip number and then setting it up). I'm sure specific services are hit or miss - there really shouldn't be a problem sending SMS to whatever number a user enters, but paternalistic snake oil salesmen gonna be paternalistic. I've had the least difficulty with Google…

Some services can definitely detect Google Voice. Chase bank won’t send SMS to voice.
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