Re: [Freetel-codec2] IP protocol over FreeDV

hello 6lowpan can work without 802.15.4 The NuttX RTOS has a generic 6lowpan implementation for embedded ARM. Sebastien Le 25/03/2018 à 10:59, Stuart Longland a écrit : > On 25/03/18 13:00, Dean H (KC4KSU) wrote: >> It’s good to hear someone else is looking at applying 6LoWPAN to amateur >>

Re: [Freetel-codec2] IP protocol over FreeDV

On 25/03/18 13:00, Dean H (KC4KSU) wrote: > It’s good to hear someone else is looking at applying 6LoWPAN to amateur > radio. > > I’ve studied 802.15.4 a fair bit.  I find the standard is growing beyond > an individual’s ability to manage.  So I distilled the 802.15.4 frame to > the essential

Re: [Freetel-codec2] IP protocol over FreeDV

Stuart, It’s good to hear someone else is looking at applying 6LoWPAN to amateur radio. I’ve studied 802.15.4 a fair bit. I find the standard is growing beyond an individual’s ability to manage. So I distilled the 802.15.4 frame to the essential pieces. My result

Re: [Freetel-codec2] IP protocol over FreeDV

Years ago I used TCP over 1200bps AX25 connections using UI frames. It worked quite well as long as you don't expect to much. Receiving an email (back when emails were just some ascii text) worked fine, but forget about protocols like HTTP. The current datalink code in freedv can compress headers

Re: [Freetel-codec2] IP protocol over FreeDV

On 25/03/18 06:25, Bruce Perens wrote: > FreeDV voice packets are around 7 bytes per 40 milliseconds. Even a > single IPV6 /address /is twice the size, not to mention the rest of the > header. So, realistic expectations are called for. Header compression is > helpful. Retransmission of a TCP

Re: [Freetel-codec2] IP protocol over FreeDV

On 3/24/18, glen english wrote: > If a whole word is lost, if the output of the decoder is silent, then it > is not possible to know if a word was missed, or if the word was never > voiced ! In analog, you might hear a noise burst and you would be aware > that some of the

Re: [Freetel-codec2] IP protocol over FreeDV

The whole idea of Codec2 was to REDUCE bit rate and redundancy. So, do what you can with structure first before adding extra stuff. I think what you need to deal with packet loss depends on the loss mechanism and the communications grade. If you randomly lose a packet (7 bytes over 40mS),

Re: [Freetel-codec2] IP protocol over FreeDV

FreeDV voice packets are around 7 bytes per 40 milliseconds. Even a single IPV6 *address *is twice the size, not to mention the rest of the header. So, realistic expectations are called for. Header compression is helpful. Retransmission of a TCP packet could easily be a 1500 or more byte repeat,

Re: [Freetel-codec2] IP protocol over FreeDV

On 3/24/18, Steve wrote: > IP is a packet protocol which requires some form of ARQ. So using the > modem would require a completely new API to mechanise that. No, this causes terrible interactions with TCP flow control. TCP already has support for retransmission and

Re: [Freetel-codec2] IP protocol over FreeDV

2018-03-24 17:11 GMT+01:00 Steve : > > I assume it would be as simple as replacing the voice payload with IP > datagrams. > > IP is a packet protocol which requires some form of ARQ. So using the > modem would require a completely new API to mechanise that. or not. You

Re: [Freetel-codec2] IP protocol over FreeDV

> I assume it would be as simple as replacing the voice payload with IP > datagrams. IP is a packet protocol which requires some form of ARQ. So using the modem would require a completely new API to mechanise that. --

Re: [Freetel-codec2] IP protocol over FreeDV

I have send IP packets with 2400A, 2400B and 800XA. Those modes have a sync word in each frame that is used to switch between data and voice frames. (And works out of the box with recent codec2 versions). It wouldn't be hard to send data with the other modems as well (as they are also just frames

[Freetel-codec2] IP protocol over FreeDV

Hi all, Has anyone attempted to send IP protocol on HF using FreeDV? I assume it would be as simple as replacing the voice payload with IP datagrams. I have a working TCP/IP modem on VHF, however it has lower weak signal performance than FreeDV. Regards, Adrian