2004.11_Projects on the Move-Free Software and Its Makers.pdf

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Free Software Projects

Projects on the Move

Free software includes such a diverse range applications that it can be hard to find the perfect tool. In this column, we

pick the best of the bunch. This month you’ll learn about the DBox2 as a video recorder, the IPv6 service provider Sixxs,

and GNU/Linux Sarge. BY MARTIN LOSCHWITZ

Open Source Community is a

typically male domain. This

prompted the female members of

the Debian project to organize

their own mailing list, [debian-

women], in an attempt to get more

women involved in the Debian

project. The first thing debian-

women came up with is a criticism

of the sexist terms used on the

Debian website. All the pages they

looked at used masculine style and

terms, and the people behind

debian-women would like to see

Debian adopt a more neutral

approach to language.

Read on for the latest on DBox2,

Sixxs, and Sarge. I have but one

request: if you can recommend a pro-

gram you would like to see featured in

Projects on the Move , email me with your

suggestion [1]. I look forward to your

comments.

added wizardry, you can also

record MPEG 2 videos and store

them on another device attached to

the network (thanks to the inte-

grated Ethernet port). In other

words, you can use the DBox as a

video recorder.

Because all DVB variants use

pure MPEG video, the recording

conditions are excellent. The

device receiving the streams simply

needs to store the video on a suit-

able storage medium. The VDR

project at [4] has developed a soft-

ware solution that does exactly

that, and makes a full-featured

DVD receiver of a normal PC with a

DVB card.

This said, it is quite expensive to

convert a standard PC into a multimedia

machine that will not spoil the looks of

your living room; and ready-made hard

disk recorders are typically in the $ 500

plus price range. The DBox2, which is

auctioned for far less at eBay, could be

just what the doctor ordered. The device

was designed for fanless operations and

makes no noise whatsoever. And it looks

a lot neater than a normal PC case. In

fact, the only piece of hardware the

DBox lacks is a hard disk. That should

be no obstacle if you say the magic

word: NFS. Tuxbox supports NFS and

has its own NFS drivers.

NFS is not difficult to set up. After

replacing the Beta-Nova software with

Linux, just load the SPTS driver (Single

Program Transport Stream) via Miscella-

neous Settings in the configuration

menu, then reboot. Of course you need

an NFS server on your LAN to store the

recordings. After rebooting the DBox,

mount the NFS directory in the network

configuration menu . The local directory

on the DBox is typically /hdd . You can

boxes. The stable versions typically

worked without any complaints and

were by far the most widespread DBox2

images. After all, compiling the Tuxbox

source code from the CVS repository is

not everyone’s idea of fun.

But in March this year, Alexander Wild

withdrew this support, and there have

been no current images since. The Yadi

(Yet another DBox2 Image) project

quickly stepped in to plug the gap left by

the Wild images. The Yadi image GUI is

very similar to Wild images with most

changes taking place under the hood.

The developers have improved the Elec-

tronic Program Guide (EPG) and added a

number of enhancements and bug fixes.

Check out [3] for more information on

installing Yadi.

Linux on the DBox2

Since the first attempts to install Linux

on the DBox2, huge improvements have

been made, not the least of which is the

installation. With a few simple steps,

users can now replace the proprietary

Beta-Nova software with Linux. And the

introduction of Tuxbox [2] gives the

DBox2 a Linux distro all of its own.

Up to the beginning of this year,

Tuxbox’s developer, Alexander Wild,

always had a current image available for

users to download and install on their

Martin Loschwitz is from a small Ger-

man town called Niederkrüchten and

a developer for Debian GNU/Linux.

Martin’s leisure time is mainly pre-

occupied with activities in the Debian

or GNU community.

Video Recording

Running Linux on your DBox not only

gives you a prettier GUI but also allows

you to leverage the benefits a normal

Linux system provides, such as complete

networking functionality. With some

November 2004

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Free software and its makers

I t is a well-known fact that the

Free Software Projects

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use the recording configuration parame-

ters to specify this directory as your

recording directory.

MPEG-2 format will still

occupy about 4GByte on

your disk, and it makes

sense to transfer your

recordings to CD or DVD

to free up enough space.

The Avidemux [6] pro-

gram removes the ads

from the files and supports

frame by frame cutting.

The export function Save

as DVD PS prevents Avide-

mux from converting the

file to a different format.

If you do not have a

DVD recorder, you can still use divx2svcd

or mencsvcd from the Mplayer suite to

convert your MPEG 2 videos to SVCD

format. Both programs have pre-config-

ured .bin and .cue files that you can burn

directly to CD. This said, a DVD recorder

does give you a lot more options.

As DVD is MPEG 2-based, there is no

need to reformat your video recordings.

The DVD Styler [7] additionally gives

you the option of adding a menu and

splash screen to your DVD. This is a use-

ful feature if you want to create a DVD

with various episodes of your favorite

soap. The menu allows you to choose

the episode you want to view.

Remote Control

To r ecord a program, simply browse the

EPG, and press the red button on the

remote when you find the right program.

You can also set up a manual timer. The

software displays a message shortly

before the recording is due to start, and

then automatically switches to the chan-

nel you want to record. If you have

DVB-S (satellite), you can even switch to

a small selection of other channels while

recording, the only restriction being that

the recorded channel and the channel

you want to view must use the same

transponder. (This explains the limited

selection.)

Neutrino, the Tuxbox GUI, automati-

cally hides any channels that you cannot

select. DVB-C (cable) and DVB-T

(antenna) do not allow you to view

another channel while recording.

Figure 2: The Sixxs Internet Points of Presence (POPs) in Europe.

application issues. The fact that most IP

addresses are assigned dynamically has

also given birth to workarounds such as

dynamic DNS. And the trend toward

connecting all kinds of electronic devices

like mobile phones, PDAs, Tvs, and even

refrigerators to the Internet aggravates

the situation even more.

If widespread connection of IP-capable

devices continues, we can expect to run

out of IPv4 address space quite quickly.

The Internet Engineering Task Force, or

IETF for short, developed version 6 of

the Internet protocol to address the

ROADS (Running Out of Address Space)

issue more than ten years ago. IPv6 has

enough addresses to assign a unique

address to every toaster. But the Internet

is slow to react. IPv6 has not been as

pervasive as expected, and there are very

few Internet service providers that actu-

ally advertise IPv6 support.

Thus IPv6 remains a domain of techni-

cally competent users and programmers.

Some backbones are accessible only via

IPv6, but since most of the Internet still

uses IPv4, users need to tunnel IPv6

packets across the IPv4 Internet.

Into the Archive

After completing a recording, you can

play videos back on the D-Box. Tuxbox

has had a movie player with this capabil-

ity for quite a while now. There should

be two files on the NFS server at this

point: one with the .ts (Transport

Stream) suffix, and another with the

.xml suffix. The latter file contains infor-

mation on the recording, and the TS file

is an image of the captured stream. It

includes the actual MPEG files but also

stores stream error correction informa-

tion. You will not need this additional

data on your hard disk; a program like

Replex [5] allows you to remove the

extras. This said, a two-hour movie in

Sixxs – IPv6 for Everyone

Although there are enough IP addresses

to go round in the US, the alarm bells

have been going off in other parts of the

world – Japan in particular – for quite a

while now. Pessimists still assume that

the IPv4 (Internet Protocol Version 4, the

current version) address space with its

four billion addresses will be running

out of space in the near future.

Registries charge a lot of money for IP

addresses. In envi-

ronments of all

sizes – from tiny

home networks to

massive enterprise

networks – users

have moved to

Network Address

Translation (called

NAT) to avoid the

expense of buying

IP addresses that

may not be used,

even though NAT

can cause various

Figure 1: Tuxbox provides a Linux distro for the DBox2.

Using IPv6 to Connect LANs

Sixxs.net [8] is a so-called tunnel broker

that gives users free acccess to the IPv6

Internet. Sixxs offers a simple IPv6 tun-

nel with a single IPv6 address. Sixxs also

offers complete IPv6 subnets, which

allow users and enterprises to attach a

whole LAN, rather than a single com-

puter, and removes the need for a

NAT-based Internet connection.

Sixxs uses a rating system to manage

quality of service. You get 25 credits for

registering. 25 credits will get you an

IPv6 tunnel with a single IP address (in

www.linux-magazine.com November 2004

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Free Software Projects

information. The clients pick

up an address from this

machine, and the routing

daemon defines routes.

Sixxs also has a service for

Internet users with dynamic

IPv4 addresses. You need to

install a heartbeat daemon on

your IPv6 endpoint to send a

signal to Sixxs every 60 sec-

onds. The heartbeat, and the

user credentials for the Sixxs

system, prove that the IPv6

endpoint is up. At the same

time, the tunnel route is

updated if the IPv6 guest has

a new IPv4 address.

September 12, by either fixing the bugs

or simply removing the packages from

the Sarge tree.

No AMD-64

The second big obstacle along the way to

the release is the Debian installer. The

new installation system already works

on all eleven architectures that Debian

supports, but the developers still need to

remove a few bugs. What Steve Lan-

gasek’s timeline also means is that Sarge

will not support AMD’s 64-bit CPUs.

The lack of AMD-64 support is defi-

nitely a blow to Debian. Let’s hope that

the new architecture makes it into the

testing tree immediately after Sarge is

released.

The period just after the Sarge release

is likely to be interesting, as the develop-

ers postponed a lot of changes to avoid

delays. One subject is the removal of any

documentation that is not covered by the

GFDL (GNU Free Documentation

License). And there is still the issue with

firmware files that do not conform with

the Debian Free Software Guidelines.

Ve rsion 3.4 of the GNU Compiler Col-

lection is also ready to go, and it

introduces a new group of ABI incompat-

ibilities. Along with these post-release

changes, the developers will finally inte-

grate the AMD-64 architecture.

If Steve Langasek’s plan works out,

Debian should be approaching the next

stable release by the time this magazine

hits the newsstands. But experience tells

us that you don’t always get what you

expect.

Figure 3: There are still too many release critical bugs in Debian.

But release assistant Steve Langasek is still convinced that

Sarge will be released on September 15.

Towns Leaves – but

Sarge Is On Its Way

Sarge is coming on Septem-

ber 15 2004. At least this is

the date that Debian Release Assistant,

Steve Langasek, quoted in his August 2

message, in which he gives general sta-

tus information for Debian GNU/Linux

3.1 (Sarge). But Steve Langasek’s mes-

sage [9] included one really big item of

news concerning Anthony Towns’ depar-

ture.

Anthony Towns has been the Debian

Project Release Manager for many years,

but in recent months he has been the tar-

get of allegations and insults, as, in fact,

have many other developers. Thus, the

step comes as no surprise to many insid-

ers. This prompted Steve Langasek’s

criticism of the developer community,

which accompanied the announcement.

Steve appealed to Debian developers to

start working towards common targets

again and bury their personal differ-

ences.

Steve’s announcement quashed

rumors of the Sarge release being post-

poned to an unspecified future date due

to Anthony Towns’ departure. Steve

announced that, in cooperation with

Colin Watson, who was promoted to

Release Assistant under Anthony Towns,

he would try to take the necessary steps

to finalize the Sarge release. The commu-

nity froze the base and standard Debian

components on July 31. Any modifica-

tions to these components need to be

okayed by the release assistants.

Steve Langasek’s timeline envisages

removing all release-critical errors before

fact, this costs you only 15 credits).

Users are given 5 credits for each week

that their IPv6 endpoint remains accessi-

ble. After just one week you have

enough credits to apply for a complete

subnet, which again costs 15 credits.

After one more week, you can even add

a nameserver for the reverse lookup

records in your subnet.

But there is also such a thing as nega-

tive credit. Five credits are deducted if

your IPv6 endpoint is down for a day.

After a week of inactivity, your endpoint

and the whole subnet are disabled. Sixxs

uses this sophisticated credit system to

ensure that the user database and the

registered tunnel are up to date. The

maintainers are also open to abuse

reports. If a user is caught abusing a

Sixxs tunnel, that user can expect to lose

his or her access privileges.

Connecting a computer to the IPv6

network takes some preparation. One

major prerequisite is an operating system

that speaks IPv6, of course. Besides

Linux, most modern systems can handle

the new protocol, including Windows

2000 and XP. Check the Sixxs pages [8]

for a HOTO on configuring the tunnel.

To support a complete IPv6 network,

you will typically need radvd (Linux) or

rtadvd (BSD). As IPv6 provides a large

number of addresses, there is no need

for a NAT gateway. However, you do

need a computer on the network to han-

dle address assignments and routing

■

INFO

[1] Tips and suggestions:

projects@linux-magazine.com

[2] Tuxbox: http://www.tuxbox.org

[3] http://developer.berlios.de/projects/yadi/

[4] VDR: http://www.cadsoft.de/vdr/

[5] Replex: http://www.metzlerbros.org/dvb/

[6] Avidemux video cutting on Linux:

http://avidemux.sf.net

[7] DVD Styler for creating DVDs:

http://dvdstyler.sf.net

[8] Sixxs IPv6 service:

http://www.sixxs.net

[9] Steve Langaseks message on Sarge:

http://lists.debian.org/debian-devel-

announce/2004/08/msg00001.html

November 2004

www.linux-magazine.com

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