Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Building a Personal VoIP System

sacredheartsc.com

Post reply on HN
Print view View original

11–20 of 150 posts

Re: Building a Personal VoIP System

#11

Post by astrobe_ »

francescovv wrote: post #2

Excellent article, and sections "NAT Problems" and "NAT Solutions" are a good starter on that topic. Except even third-choice solution is not always feasible. Reserving fixed RTP/UDP port range is not possible with carrier-grade NAT, which is quite common with residential ISPs and nearly-universal with cell ISPs. Fourth-choice would be to reserve port range on a personal server (which would run B2BUA, asterisk in OP'…

One often sees the STUN, TURN or ICE protocols around SIP-based VoIP, I believed they were supposed to help solve those issues?

Re: Building a Personal VoIP System

#12

Post by stonewall »

fulafel wrote: post #3

Would be interesting to hear why they use v4+nat and face the described problem. First thought was maybe they bought some very old phones without v6 support - but the models he recommends don't seem to have this problem based on a googled datasheet.

(Author here.) Sadly its a lot less interesting: my home ISP still doesn't support IPv6.

Re: Building a Personal VoIP System

#13

Post by nicolaslem »

KaiserPro wrote: post #8

my wife had a requirement: be able to have an intercom for the house and shed. We used to have a baby monitor, but that was one way, for one room. Now we need many more rooms to talk to each other. I looked at some intercoms on amazon/ebay, they are all RF and a bit shit. I saw some wifi ones, but nothing cheap enough to take a punt on. I did think about trying to make something with an ESP32, but that would be too h…

I remember playing with an old device as a child at my grandparents' place, it was similar to a walkie-talkie but transmitting using the mains power instead of RF. It was supposed to plugged to a socket and hanged on the wall. It was made exactly for the use case you describe, as an intercom between rooms. It even had a button to ring a bell in another room.

Re: Building a Personal VoIP System

#15

Post by TacticalCoder »

Ah good memories! Even though I knew nothing about VoIP I installed, years ago, one at my wife's little SME using "RasPBX" (a distro made of Raspbian + FreePBX + Asterisk) running on a... Raspberry Pi 1 (maybe a Pi 2 but I'm pretty sure it was a 1). The Pi was booting from the SD card but everything was running on an external HDD.

I did put six Cisco VoIP phones and all was working fine as long as no more than four phones were used simultaneously (which never happened). It worked for years like that and wife ended up selling her SME with these VoIP phones still hooked to the RPi 1. We warned them that that thing was kinda a hack ; )

For anyone hesitating: it's not hard to set up. Find a provider to get a SIP trunk, configure the thing, backup the config (I just imaged the entire drive), and you're good to go for a very long time.

It's simple, reliable, stuff that usually won't move under your feet.

Re: Building a Personal VoIP System

#16

Post by deno »

astrobe_ wrote: post #11
francescovv wrote: post #2

Excellent article, and sections "NAT Problems" and "NAT Solutions" are a good starter on that topic. Except even third-choice solution is not always feasible. Reserving fixed RTP/UDP port range is not possible with carrier-grade NAT, which is quite common with residential ISPs and nearly-universal with cell ISPs. Fourth-choice would be to reserve port range on a personal server (which would run B2BUA, asterisk in OP'…

One often sees the STUN, TURN or ICE protocols around SIP-based VoIP, I believed they were supposed to help solve those issues?

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 at some point. It’s a really weird default.

Re: Building a Personal VoIP System

#19

Post by jelly »

wnolens wrote: post #6

Cool to read someone indulge in this. For others interested with no prior context, also consider FreeSWITCH. Personal experience: I spent about 15 months working for a local telecom company, supporting their asterisk servers and developing interactive voice response applications. I was given the opportunity to build their residential voip service (in 2010?) from scratch and despite asterisk being so dominant I protot…

I took a look at freeSWITCH's site and it looks like they got bought out. Their documentation is a total mess because the acquiring company has imported lots of wiki pages without much care for how they fit together.

Re: Building a Personal VoIP System

#20

Post by irusensei »

I’ve used to live in an inter generational big house (Italians am I right… even if we are not actually born there we still have spaghetti dna). Anyway I’ve setup one very lightweight asterix instance of statically defined accounts. A few cheap voip phones were installed through the house plus soft phones on personal smartphones.

It was supposed to make things more convenient. Supposed to, because we just kept yelling to convey messages. When I’ve moved out I’ve dismantled the system since I wouldn’t be there to keep it maintained.

Post reply on HN