Add SLIP protocol in FSFW #460

New Issue

muellerr · 2021-08-16T09:36:35+02:00

muellerr commented

2021-08-16 09:36:35 +02:00

The current framing protocol DLE seems not be standardised in some way, and the only Python library I found is this one: https://github.com/Lx/python-dlestxetx
which appears to implement it differently than the FSFW.

I suggest to add SLIP to the FSFW because it seems to be standardized via RFC 1055 and libraries seem to be more common for it (see https://pypi.org/project/sliplib/ and https://docs.rs/serial-line-ip/0.5.0/serial_line_ip/)

The current framing protocol DLE seems not be standardised in some way, and the only Python library I found is this one: https://github.com/Lx/python-dlestxetx which appears to implement it differently than the FSFW. I suggest to add SLIP to the FSFW because it seems to be standardized via [RFC 1055](https://datatracker.ietf.org/doc/html/rfc1055.html) and libraries seem to be more common for it (see https://pypi.org/project/sliplib/ and https://docs.rs/serial-line-ip/0.5.0/serial_line_ip/)

muellerr added the

feature

label 2021-08-16 09:45:13 +02:00

mohr referenced this issue

2021-08-30 13:09:06 +02:00

DLE Encoder #466

mohr commented

2021-08-30 13:27:05 +02:00

I do not see the argument of there being no library for our DLE implementation, as it does not take much time to write one for it being really simple.

As for stadardization, in a way it is standardized by ASCII which defines the control characters STX, ETX and DLE, but is very vague about the actual use of DLE, which leads to different implementations. As I said in 466, I mainly see it being used within fsfw code, where the standardization problem is easily controlled.

As for SLIP, feel free to implement it, but I do not see much use for it, as I prefer our implementation of DLE encoding for it having an unambiguous start of frame character. Both provide an unpredictable encoded length, SLIP being a bit smaller only encoding two control characters vs DLE encoding four (or three if we would get rid of CR escaping).

I do not see the argument of there being no library for our DLE implementation, as it does not take much time to write one for it being really simple. As for stadardization, in a way it is standardized by ASCII which defines the control characters STX, ETX and DLE, but is very vague about the actual use of DLE, which leads to different implementations. As I said in 466, I mainly see it being used within fsfw code, where the standardization problem is easily controlled. As for SLIP, feel free to implement it, but I do not see much use for it, as I prefer our implementation of DLE encoding for it having an unambiguous start of frame character. Both provide an unpredictable encoded length, SLIP being a bit smaller only encoding two control characters vs DLE encoding four (or three if we would get rid of CR escaping).

mohr commented

2021-10-01 14:28:03 +02:00

Do you plan on implementing SLIP? If not, I would vote for closing this issue.