freebsd-hackers Digest, Vol 364, Issue 6
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Today's Topics:
1. Google Summer of Code 2010 ideas (Atis)
2. Re: Google Summer of Code 2010 ideas (Harti Brandt)
3. Re: Google Summer of Code 2010 ideas (Atis)
4. Re: Google Summer of Code 2010 ideas (Harti Brandt)
5. [freebsd-hackers] need to edit /etc/ttys for console login
(Mike Winter)
6. Re: [freebsd-hackers] need to edit /etc/ttys for console
login (Garrett Cooper)
----------------------------------------------------------------------
Message: 1
Date: Fri, 19 Mar 2010 15:36:25 +0200
From: Atis <the...@gmail.com>
Subject: Google Summer of Code 2010 ideas
To: freebsd...@freebsd.org
Message-ID: <7f9bf5711003190636k1...@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Hello,
I'm looking forward to participating in Google Summer of Code 2010.
Interested in networking related projects. I have a little previous
FreeBSD experience (no programming), but I have ~5 years industry
C/C++ programming experience, some familiarity with Linux kernel, and
interest in learning something new :)
>From reading http://www.freebsd.org/projects/ideas/index.html and
http://wiki.freebsd.org/Networking I selected some projects of
interest. Since not all of them have their respective mentors
mentioned, I'm sending this to the list.
Potential projects:
1) TCP/IP regression test suite
This project idea already was included in previous years, and there
was some work done by Zach Riggle (2009), Victor Hugo Bilouro (2008)
and by Nanjun Li (2007). Could you give a broad outline what features
of this project were already completed by the work in previous summers
of code, and what new work is expected to be done in this year?
Weren't their results good enough or were they simply incomplete? I
realise that a complete TCP test suite could be a huge effort, but
exactly what features are missing? Is the work of this year supposed
to be build on the work by previous years, or to start something new?
2) SCPS, Space Communication Protocol Standards
This is probably my first project choice if all goes well. Space
protocols - this sounds very cool :) and is related to my research
interests (IP protocols over lossy networks). The first question is -
do these protocols also have some practical value? This is not-so-new
family of protocols, but it seems that very few implementations exist.
On the one hand, this could be a good thing, because now there a
chance for FreeBSD to be the first OS with open source SCPS
implementation. On the other hand - lack of use seems to imply lack of
importance and usefulness. The second question - is complete
implementation of all the protocols supposed? At first glance it seem
that e.g. SCPS Security Protocol simply duplicates the functionality
already present in IPSec. Still, support for all protocols may be
needed for interoperability and completeness of the implementation.
Also, the amount of work required for this project is very unclear at
the moment.
3) "Implement optimized trie lookups for forwarding.", from
http://wiki.freebsd.org/Networking.
Even though this is not listed as "summer of code" idea, it sounds
interesting, but what exactly does this task imply? Was there some
mailing list discussions related to the problems with current approach
and potential improvements? (What keywords to use in search?) The
first improvement idea that comes in mind is to replace the old radix
tree with a kind of LPC-trie, but does that make sense? In any case,
this project probably is over my head, especially the issues with SMP
and locking. Maybe in the future? :)
My initial ideas also included experimenting with a kind or routing
cache for FreeBSD, but after reading some (very interesting) old
mailing list discussions I gave up these thoughts :)
So, which one of these three ideas would be the most useful and
feasible? Or would you suggest something completely else for someone
with my background?
--
~Atis
------------------------------
Message: 2
Date: Fri, 19 Mar 2010 15:25:25 +0100 (CET)
From: Harti Brandt <hartmut...@dlr.de>
Subject: Re: Google Summer of Code 2010 ideas
To: Atis <the...@gmail.com>
Cc: FreeBSD...@freebsd.org
Message-ID: <2010031915...@beagle.kn.op.dlr.de>
Content-Type: TEXT/PLAIN; charset=US-ASCII
Hi,
On Fri, 19 Mar 2010, Atis wrote:
A>2) SCPS, Space Communication Protocol Standards
A>This is probably my first project choice if all goes well. Space
A>protocols - this sounds very cool :) and is related to my research
A>interests (IP protocols over lossy networks). The first question is -
A>do these protocols also have some practical value? This is not-so-new
A>family of protocols, but it seems that very few implementations exist.
A>On the one hand, this could be a good thing, because now there a
A>chance for FreeBSD to be the first OS with open source SCPS
A>implementation. On the other hand - lack of use seems to imply lack of
A>importance and usefulness. The second question - is complete
A>implementation of all the protocols supposed? At first glance it seem
A>that e.g. SCPS Security Protocol simply duplicates the functionality
A>already present in IPSec. Still, support for all protocols may be
A>needed for interoperability and completeness of the implementation.
A>Also, the amount of work required for this project is very unclear at
A>the moment.
Acctually the definition of these protocols has been taken over by CCSDS
(ccsds.org). I think they are now in some of the green or blue books
(cannot remember the color). There is some heavy push in the satellite
community on moving towards CCSDS protocols so, for sure, there is
practical value in the corresponding communities. I cannot answer the
question to what extend an implementation is required. I know that we have
some activity in the lower layers and that the upper layers are also used
(file transfer, for example). Don't know about networking and security,
though.
harti
------------------------------
Message: 3
Date: Fri, 19 Mar 2010 17:50:10 +0200
From: Atis <the...@gmail.com>
Subject: Re: Google Summer of Code 2010 ideas
To: Harti Brandt <ha...@freebsd.org>
Cc: FreeBSD...@freebsd.org
Message-ID:
<7f9bf5711003190850i60...@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
On Fri, Mar 19, 2010 at 4:25 PM, Harti Brandt <hartmut...@dlr.de> wrote:
> Hi,
>
> On Fri, 19 Mar 2010, Atis wrote:
>
> A>2) SCPS, Space Communication Protocol Standards
> A>This is probably my first project choice if all goes well. Space
> A>protocols - this sounds very cool :) and is related to my research
> A>interests (IP protocols over lossy networks). The first question is -
> A>do these protocols also have some practical value? This is not-so-new
> A>family of protocols, but it seems that very few implementations exist.
> A>On the one hand, this could be a good thing, because now there a
> A>chance for FreeBSD to be the first OS with open source SCPS
> A>implementation. On the other hand - lack of use seems to imply lack of
> A>importance and usefulness. The second question - is complete
> A>implementation of all the protocols supposed? At first glance it seem
> A>that e.g. SCPS Security Protocol simply duplicates the functionality
> A>already present in IPSec. Still, support for all protocols may be
> A>needed for interoperability and completeness of the implementation.
> A>Also, the amount of work required for this project is very unclear at
> A>the moment.
>
> Acctually the definition of these protocols has been taken over by CCSDS
> (ccsds.org). I think they are now in some of the green or blue books
> (cannot remember the color). There is some heavy push in the satellite
> community on moving towards CCSDS protocols so, for sure, there is
> practical value in the corresponding communities. I cannot answer the
> question to what extend an implementation is required. I know that we have
> some activity in the lower layers and that the upper layers are also used
> (file transfer, for example). Don't know about networking and security,
> though.
>
> harti
>
Thanks for the reply. Looks like I will cross this project out from my list.
I have found that there is even a reference implementation of SCPS protocols:
http://www.openchannelsoftware.com/projects/SCPS.
It's usable from FreeBSD too, because they have implemented everything
in userspace, probably to achieve portability. I wonder whether it
would make sense to rewrite it or some parts of it (TCP "performace
enchancing proxy" is the interesting one) for kernel mode.
Theoretically, that should mean better latency, and no data copy
overheads, right? But then again, satellite link bandwidths probably
are too small to make such improvements important.
--
~Atis
------------------------------
Message: 4
Date: Fri, 19 Mar 2010 16:59:27 +0100 (CET)
From: Harti Brandt <hartmut...@dlr.de>
Subject: Re: Google Summer of Code 2010 ideas
To: Atis <the...@gmail.com>
Cc: FreeBSD...@freebsd.org
Message-ID: <2010031916...@beagle.kn.op.dlr.de>
Content-Type: TEXT/PLAIN; charset=US-ASCII
On Fri, 19 Mar 2010, Atis wrote:
A>On Fri, Mar 19, 2010 at 4:25 PM, Harti Brandt <hartmut...@dlr.de> wrote:
A>> Hi,
A>>
A>> On Fri, 19 Mar 2010, Atis wrote:
A>>
A>> A>2) SCPS, Space Communication Protocol Standards
A>> A>This is probably my first project choice if all goes well. Space
A>> A>protocols - this sounds very cool :) and is related to my research
A>> A>interests (IP protocols over lossy networks). The first question is -
A>> A>do these protocols also have some practical value? This is not-so-new
A>> A>family of protocols, but it seems that very few implementations exist.
A>> A>On the one hand, this could be a good thing, because now there a
A>> A>chance for FreeBSD to be the first OS with open source SCPS
A>> A>implementation. On the other hand - lack of use seems to imply lack of
A>> A>importance and usefulness. The second question - is complete
A>> A>implementation of all the protocols supposed? At first glance it seem
A>> A>that e.g. SCPS Security Protocol simply duplicates the functionality
A>> A>already present in IPSec. Still, support for all protocols may be
A>> A>needed for interoperability and completeness of the implementation.
A>> A>Also, the amount of work required for this project is very unclear at
A>> A>the moment.
A>>
A>> Acctually the definition of these protocols has been taken over by CCSDS
A>> (ccsds.org). I think they are now in some of the green or blue books
A>> (cannot remember the color). There is some heavy push in the satellite
A>> community on moving towards CCSDS protocols so, for sure, there is
A>> practical value in the corresponding communities. I cannot answer the
A>> question to what extend an implementation is required. I know that we have
A>> some activity in the lower layers and that the upper layers are also used
A>> (file transfer, for example). Don't know about networking and security,
A>> though.
A>>
A>> harti
A>>
A>
A>Thanks for the reply. Looks like I will cross this project out from my list.
A>I have found that there is even a reference implementation of SCPS protocols:
A>http://www.openchannelsoftware.com/projects/SCPS.
A>It's usable from FreeBSD too, because they have implemented everything
A>in userspace, probably to achieve portability. I wonder whether it
A>would make sense to rewrite it or some parts of it (TCP "performace
A>enchancing proxy" is the interesting one) for kernel mode.
A>Theoretically, that should mean better latency, and no data copy
A>overheads, right? But then again, satellite link bandwidths probably
A>are too small to make such improvements important.
PEPs are a big issue for the satellite people. With DVB-S2 over a 40MHz
transponder you can get 60-80MBit/s if you have good whether. With a RTT
of 600ms or more getting TCP to an acceptable speed gets quite tricky. Of
course not all people can afford a full transponder, but even a shared
link DVB-S2 + RCS requires tuning...
I don't know what bitrate you can get in a Docsis system, but I would
assume that it is comparable.
There are also a lot of commercial users of different VSAT systems, but I
have no idea what the share of FreeBSD is in these systems.
harti
------------------------------
Message: 5
Date: Fri, 19 Mar 2010 11:26:57 -0700
From: Mike Winter <mike....@comcast.net>
Subject: [freebsd-hackers] need to edit /etc/ttys for console login
To: freebsd...@freebsd.org
Message-ID: <CF7355EA-2B8B-4ED7...@comcast.net>
Content-Type: text/plain; charset=us-ascii
version 7.2 from cd. I installed freebsd 7.2 after booting from cd, going to prompt and doing set console="comconsole".
When I go to edit the /etc/ttys sysinstaller is just putting me back to prior menu. When I try through the sysinstall menu showing functions it says the file does not exist!
Without setting ttyd0 to 'vt100 no' I cant get a login prompt on console once I pull the cd and want access to console - before I can remote ssh in.
Pertinent advice and 'please use other mailer' responses welcome.
- Mike
------------------------------
Message: 6
Date: Fri, 19 Mar 2010 18:45:21 -0700
From: Garrett Cooper <yane...@gmail.com>
Subject: Re: [freebsd-hackers] need to edit /etc/ttys for console
login
To: Mike Winter <mike....@comcast.net>
Cc: freebsd...@freebsd.org
Message-ID:
<7d6fde3d1003191845w4de...@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
On Fri, Mar 19, 2010 at 11:26 AM, Mike Winter <mike....@comcast.net> wrote:
> version 7.2 from cd. I installed freebsd 7.2 after booting from cd, going to prompt and doing set console="comconsole".
>
> When I go to edit the /etc/ttys sysinstaller is just putting me back to prior menu. When I try through the sysinstall menu showing functions it says the file does not exist!
>
> Without setting ttyd0 to 'vt100 no' I cant get a login prompt on console once I pull the cd and want access to console - before I can remote ssh in.
>
> Pertinent advice and 'please use other mailer' responses welcome.
A question better for questions@, but since we're here...
1. Boot a LiveCD.
2. Go into a rescue shell.
3. Mount your root under /mnt .
4. Fire up your favorite editor editing /mnt/etc/ttys (memory serves
me correctly your choices are /rescue/ee and /rescue/vi ).
5. Save.
6. reboot.
Cheers,
-Garrett
------------------------------
End of freebsd-hackers Digest, Vol 364, Issue 6
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