Hello
I’m installing a small WISP and I want to offer Internet 1Mbps and IP Telephony to my customers.
I’ve 2 Internet connections one ADSL (1Mbps/512Kbps) and one cable (4Mbps/512Kbps) the idea is provide 512K internet plans.
Now my question is:
how can I use the cable connection (4Mbps/512Kbps) only for Internet (and if the ADSL fails use it also to transmit the voip packets). And the ADSL (1Mbps/512Kbps) only for voip and only if Cable connection fails (use up to 512Kbps/128Kbps of the ADSL bandwidth) for backup??
The idea is to provide an excellent voice service.
PS: For AP I’ll use Ubiquiti Bullet2HP and for CPE I’ll use Ubiquiti NanoLoco2 and Nano2 (for long distance)
You’ve nowhere near enough upstream bandwidth to consider voip services of any scale, especially as your emphasis is on quality. Each VOIP circuit will use 64k of your upstream (protocol dependent) as well as other network overhead. In reality, you’d be lucky to manage 4 simultaneous voip transmissions with such little bandwidth, taking into account other overhead.
Can you not get any syncronous bandwidth instead of using DSL connections (Which is not the thing to base a business on IMO) Also, most providers do not allow reselling of their services, so a dedicated connection is the only way to go.
In answer to your question though, you could acheive something near what your asking by packet marking, and sending the voip traffic to it’s own gateway, whilst having a default route for other traffic. There are loads of examples in the forums here.
G729 with a payload size of 20ms will consume 40 Kbps upload AND 40 Kbps download with 50 pps up and 50 pps down. G711 with a payload size of 20ms will consume 80 Kbps upload AND 80 Kbps download with 50 pps up and down as well. You have to take packets-per-second (pps) and bandwidth into account.
With my ADSL connection I’ve near 100% of the max speed (national bandwidth,international bandwidth an average of 50%)…
Then can I carry 10 G729 (20ms payload) calls with my ADSL connection? or you really consider that it’s no way.
The problem you have, is that any cable or DSl service is a contended one. There will be points that you are sharing that upstream with others on the same circuit, and if you have voice calls going on at that time, then your calls will suffer or drop.
Your original post emphasys was on the word “quality.” What we’re telling you, is there is no way of gauranteeing that using dsl or cable connections. You need uncontended, dedicated bandwidth for any voip service.
Your looking at a best-case scenario, providing you get every bit of bandwidth constantly to provide X amount of simultaneous voip calls. The reality though, is you won’t get the the max bandwidth all the time on any contended service, so you will not be able to provide a quality service on those types of connections. The reality is, you cannot run any business on DSL/cable connections properly. I know it’s the only option for some. Can you not get an ISDN circuit in where your cable/dsl modems are located and run the voip through those? That would work perfectly.