

📞 Elevate your office calls with secure, lightning-fast VoIP connectivity!
The Grandstream HT-812 2FXS Gateway is a compact, powerful ATA device designed to bridge analog phones with modern VoIP networks. Featuring 2 FXS ports, dual Gigabit Ethernet, a built-in NAT router, and advanced TLS/SRTP encryption, it delivers exceptional voice quality and secure communication for home and office environments.
| ASIN | B01M2ZJQAF |
| Best Sellers Rank | 93,222 in Computers & Accessories ( See Top 100 in Computers & Accessories ) 709 in Routers |
| Guaranteed software updates until | unknown |
| Item model number | HT-812 |
| Language | Dutch |
| Manufacturer | Grandstream |
| Product Dimensions | 22.86 x 33.02 x 7.11 cm; 290 g |
T**E
Compatible with Zen's UK "BT digital voice" switchover
Bought as I'm a zen.co.uk customer, and have UniFi throughout the house (I don't use the Fritzbox). With the BT/UK "digital voice" switchover in full-swing, I wanted a means to keep our old land line alive. This worked perfectly. Configuration hasn't been utterly straight-forward, but I've finally found the following settings work (for Zen customers): - Ensure your NAT/firewall is forwarding the required ports through to the Grandstream (5060/UDP from 212.23.7.228, and 20000-30000/UDP from 62.3.88.0/28 and 62.3.88.16/28) - Primary SIP server: voip.zen.co.uk - Secondary SIP server: voip2.zen.co.uk - Prefer Primary SIP server: No - Outbound proxy: Blank/None - Allow DHCP Option 120: No - SIP Transport: UDP - NAT traversal: No - DNS Mode: A Record - DNS SRV: No - Fallback Timer: 60 - Use Request Routing ID in SIP INVITE Header: No - Sip Registration: Yes - Outgoing Call without Registration: Yes - Register Expiration: 5 - Enable SIP OPTIONS/NOTIFY keep alive: No - Local SIP port: 5060 - Local RTP port: 5004 - Random SIP port: No - Random RTP port: No - Enable RTCP: Yes - Hold Target Before Refer: Yes - Refer-To Use Target: No - Remove OBP: No - Support SIP Instance ID: Yes - Validate Incoming SIP Message: No - Use Privacy Header: No - Use P-Preferred-Identity Header: Yes - Use P-Access-Network-Info Header: Yes - Use P-Emergency-Info Header: Yes - Use P-Asserted-Identity Header: No - SIP REGISTER Contact Header Uses: LAN - Caller ID Fetch Order: Auto - DTMF: RFC2833 - SLIC: UK - Caller ID Scheme: SIN 227 - Dial Plan: (You may want to customise) ... { 999 | 10[015] | 11[129] | 11[68]xx | 1[45]7[1-2] | <0=44>8001111 | <0=44>845464x | <0=44>[1235789]xxxxxxxxx | <=441638>23456789]xxxxx | 1410[1235789]xxxxxxxxx | x+ }
I**Y
Great Device for VOIP phone calls but software UI is terrible.
The device works perfectly since Vodafone switched to VOIP Phone. I didnt want to use the terrible router which doesnt support bridge mode either. This device is a great solution to continue using my custom router. However, the firmware UI is the major and only downside to using this device. It has the worst UI I have ever seen compared to other Grandstream products and possibly every other routers and ATA firmware UIs I've seen. I stand corrected when I thought D-Link had the worst UI. Its as if it was built out of Adobe's Dreamweaver from back in the old days. I'll change my review, if Grandstream fixes this. Aside from the horrible UI, the setup process is deceptively simple. It looks bloated with many options but you only need a few to set it up. Some general tips for anyone setting up for Vodafone Broadband. However, this may get outdated/changed from the time of writing: -The device doesnt come with a manual so use the Grandstream Documenation on the official website. Just type 'grandstream HT812' on google and click on the link that leads you to official grandstream product page. From there, just look for anything that will lead you to HT812/HT814 user manual as websites get updated and location may change. -For vodafone setup configuration, type 'Landline phone with own router on FTTP' on google and look for anything that will take you to the vodafone forums. Once you ahve reached the forum thread, go to page 9 and scroll down until you see setup instructions.
C**S
Provided introduction to VOIP
The imminent arrival of FTTP prompted the investigation of VOIP to allow the ditching of the increasingly expensive landline which is now only used by ageing relatives and neighbours who have not moved to mobile. Since I do not intend to make outgoing calls, Sipgate provides a low cost (free), local number to which I can later migrate my BT number if it works well (at additional cost). The HT-812 allows the use of my existing analogue phones to assess the performance/reliability of VOIP as an alternative to the existing copper landline so I can use the money saved to pay for fast FTTP. Configuration is somewhat daunting due to the huge number of settings in the configuration GUI but only a few need changing. After updating the firmware to the latest version (see online manual) there are even more options available but most VOIP providers do supply settings for this series of adapters as well as the SIP codes, passwords etc. I also made these additional changes to make my phones sound like BT phones rater than US ones. In Advance Settings:- System ring cadence: c=400/200-400/2000; Dial tone: f1=350@-19,f2=450@-22,c=0/0; You will need one (or two) RJ11 (male) to BT (female) adapters in order to plug in your existing phones. For traditional phones these need to be masters including the ring capacitor. For modern DECT base stations the capacitor does not seem to be required. For my experiment I had to resort to adding some old ADSL filters which contain the ring capacitor, to my adapter cables. So to the results. The HT812 works perfectly. Audio quality is better than the landline but otherwise I can see no difference. I will have to see what the reliability of the VOIP service is but for the very low number of calls it will probably not matter. I will be migrating my BT number and then will enjoy not having to pay the line rental costs which will soon recoup the cost of the HT812! Do remember that migrating your number will cease the existing copper line and all services including ADSL/FTTC. If this appears too complex a process then it might be better to pay for Digital Voice (the same thing but configured by your ISP), but for my use case the VOIP gateway is an attractive option.
R**L
Should not be sold to UK or European clients without correct power adpater
Total waste of time and money - Bought this thinking it would come with a UK plug, not even realising it was going to be shipped from the US - so it arrived only with US 2 prong plug - no good for the UK. Will not waste time trying to source a power adpater 12v at the right amperage, even if the 60hz doesn't affect the operating not willing to risk. SO want to return the item - Amazon have ordained they will allow me to return the item - either I pay for the return myself or I can print a label and drive to a UPS drop off point - I am rural, so this is going to take time and money - not to mention the label they have provided is several pictures on the web page which you have to screen grab to print. When the itme was delivered it was left in a pool of water - great for an electrical item! Now I am off to start my research again to find another item to work on my network - What a waste of time, money and effort, not even going to mention the amount of CO2 we could of avoided if AMazon had been honest on the description in the first place!!
U**S
Fabulous Gizmo (ATA) - but not trivial to set up!
I moved ISP's to one to another VSDL account (still - no FTTP here quite yet) which was data only - no associated land line. I wanted a static phone as well as my mobile for business reasons. This device dovetails nicely with Number People (look them up) especially if you only have inbound calls on the line (which I do ... mostly). I have the WAN port connected to my LAN (just a static address on my home LAN) and do not use it routing capability. I only use one phone (RJ11 - USA style) socket connected to a DECT phone base station with 4x handsets. The base station also has an RJ11 socket so I needed an ADSL modem style (RJ11 male to RJ11 male) cable to connect them up. The HT812 power plug comes with a USA style plug (will utilize 110V to 250V) so you also need a USA to UK plug adaptor. I work in IT but am no expert on VOIP. I had to read the instructions on the Number People site for a while (set Primary SIP Server to customerNNNNNNN.vo-ip.co.uk (Profile 1 Page) and SIP User ID, Authenticate ID, Password and Name (FXS Ports Page). That's pretty much it. Leave everything else well alone! The HT-812 generates dial and ringing tones itself. Quality is excellent - no dropout and no different from any (clear) analogue line.
A**N
Setting up takes some work. Call quality is fine.
Bought this HT512 to replace a Linksys pap2t which had died. The Grandstream shipped from USA and arrived with a USA power supply so first thing needed was a UK to USA mains adapter. Also included was a network cable. There was no user guide included (but this can be downloaded from the Grandstream website) and no phone tails to convert RJ11 to UK telephone socket. Luckily I could use the old Linksys tails. The HT512 has a WAN port and a LAN port which do different things. The WAN port is what you normally expect and is used to connect to an existing LAN (like on the |Linksys). The LAN port is a built in router/dhcp server etc. I was replacing an existing device so the WAN port is what I needed (not LAN). I used the web interface to set up the HT512. For setting up the 2 telephones, you need to get the settings from your SIP provider. Mine (Sipgate) had generic instructions for the Grandstream HT series. These showed all the settings on a single config screen, however this HT512 had the settings spread over 3 different screens. However, after finding where everything should go, I plugged the phone in and fired it it with a test call. It worked first time. In summary, the HS512 had a few shortcomings (no manual, USA power supply, no UK tails) and required a fair bit of detective work to set up but as a replacement for the Linksys pap2t, it is ideal. Even if the built in router/dchp server (LAN port) is not required.
S**N
See the review
I bought this after reading helpful and detailed feedback from previous purchasers. It is an excellent product, delivered promptly, good value, everything as it says on the can. It came equipped with the latest firmware, so no update required. A very detailed manual is downloadable. As others have said, setup appears quite daunting, but you only have to change a few parameters - but which ones?. You connect the WAN port on the product (ATA) to a LAN port on the router, Plusnet Hub2 in my case (note; ignore the BT phone connector on the router because Plusnet currently do not provide a voip service). You need a telephone number and an address to connect to a SIP server. I went to the website of Number-People, who are incredibly helpful provided both for just £1/month, so it was just a question of entering their info in to the ATA config file. Note that some Number-People menu choices may not work if you have adblocking or other extensions active on your browser. I was using Firefox but had to switch to Google Chrome to get around this. They give you a port number (5060) which you overwrite on the default port number given in the ATA config file. Then you need to open that port in the router configuration by setting up port forwarding to allow voip call forwarding through the firewall. Then all works fine.
G**P
VOIP ATA
I switched to a VOIP service and wanted to keep my existing telephones. This requires use of an ATA. I found that the manufacturers of these devices provide lots of specifications on them, but the REN is not always so easy to find unless you download and search the manuals. This unit is REN 3, and was one of the main factors in choosing this model over others (The HT814, for example, is only REN 2). The unit is quite small and is not unattractive. It was delivered extremely quickly by the supplier. It arrived in a plain white box with a power supply and some cables. You will likely need to purchase an additional adapter to convert the socket(s) to mate with the BT style items on your existing telephone lead(s). There is no manual supplied, so you need to download a PDF. I suspect many people will struggle to get this working without some cursing. I expected I may have some issues, so I also purchased a telephone when I set up my account. This came preconfigured and functioned out of the box. I used the settings from this to fill out the relevant boxes in the HT812 configuration pages and it was soon working. It would have taken me much longer without this information. It is not really fair to expect your VOIP provider to get a device working that they did not provide and likely know little about. The amount of settings that can be changed is high. None of the default settings need to be altered to make the unit work. The default settings appear intended for use in the USA (ringtones etc.). There is a great page on the web that lists all the settings you need to change to make it more suitable for a UK environment. Kudos to that person. Remember to change the device password, or you may find unscrupulous internet types racking up a large telephone bill at your expense.
D**W
Great way to save your landline number
Although landlines are largely replaced with cell phones, you may have a reason to hold onto an old number. This was the case for us having owned a line for many years, but the rising costs had become unreasonable ($45/mo), just to keep a line that rarely gets used. I began looking at alternatives, and two stood out: give up the line entirely, or port the number to a VoIP provider. Some of you might say to port the number to a cell plan, but even $15 per month on a prepaid plan would feel wasteful. So, before ditching the line, I looked into VoIP, which honestly is a bit confusing. Some providers sell hardware/devices and bundle the service with that, others use stand-alone devices. I looked into the bundled service + device route first but those seem to have really bad customer service or quality of service reviews. Their pricing can also be quite deceptive on what you would actually pay. After that I saw a few recommendations for a VoIP provider based out of Canada as having great pricing and works with a variety of stand-alone devices like this Grandstream. I went this route and am very pleased with the result. For starters, my family can’t even tell anything changed. After a few days my landline number ported successfully to the new provider. Incoming and outgoing calls work just like they did before, and the sound quality seems the same. The Grandstream device itself works great. I am not using this as a router, I just plug it into an open LAN port on my network, and then run a line to my existing cordless home phone. It is small, doesn’t get very warm, and isn’t obnoxious with its indicator lights. Programming the device to connect with the VoIP provider did require following a guide, and the UI isn’t the best looking but gets the job done. The good thing is once you get it connected and working, you’ll probably never need to touch it again. Opportunities for improvement - Updating to the latest firmware is confusing – why is the wrong update URL set at the factory? I was able to update after finding instructions online. Also, the WebUI feels like a throwback to setting up an old router from the 90s.
L**S
Funciona, sólo para expertos en el área de redes
Lo probé con Megacable conectando el módem a modo puente con este dispositivo usando la VLAN 559 y funciona de maravilla. Es importante que la cuenta SIP se puede tener activa en un dispositivo a la vez.
M**K
Works great with Starlink
Just been fitted. Very happy. Great idea if you don't want a normal house telephone line. Works great with Starlink.
G**N
Erfüllt voll und ganz seinen Zweck
Das Gerät an sich ist gut verarbeitet. Leider fehlt eine vernünftige Bedienungsanleitung, daher auch nur 2 Sterne für die Installation. Doch dank der genauen Beschreibung von Herrn Müller, konnte auch ich als Leihe das Gerät installieren und programmieren. Jetzt verrichtet es seinen Dienst. Es folgt auf ein DECT Gerät der Firma Wantec, was von der Installation her wesentlich einfacher gestaltet war, da es über Funk arbeitet. Allerdings war dieses Gerät mal wieder defekt (in 5 Jahren das 4) und auch nicht mehr zeitnah lieferbar. Der Grandstream kam schon einen Tag früher als angekündigt und ist auch recht ansehnlich. Über die Haltbarkeit kann ich natürlich noch nicht wirklich Auskunft geben, da er erst seit heute in Betrieb ist. Ich kann jedem nur empfehlen die Anleitung zur Einrichtung von Herrn Müller zu nutzen, dann funktioniert auch alles.....
Q**R
Buen producto
Funcionamiento correcto, se puede poner el idioma español, no tiene manual de ningún tipo, por lo que sí no entiendes un poco la configuración de hace muy difícil. La calidad de la voz excelente .
Trustpilot
3 weeks ago
4 days ago