Setting up Server

Hi all,

i have a network specific question, sorry for asking here.

I set up 3G network connection with a Huawei stick. Connection to internet
works well, but i can not connect to the board from the internet. Even ping
gets no answer.

IP-Forwarding is enabled in kernel and /proc/sys/net/ipv4/ip_forward

My pppd options:
/dev/ttyUSB0
modem
crtscts
lock
connect "/usr/sbin/chat -f /etc/chatscripts/provider"
noauth
noipdefault
defaultroute
usepeerdns

Chatscript:
ABORT RING
ABORT "NO CARRIER"
ABORT ERROR
ABORT "NO DIALTONE"
ABORT BUSY
ABORT "NO ANSWER"
REPORT CONNECT
ECHO OFF
''  AT
TIMEOUT 10
OK-+++-OK ATZ
OK  AT+CGDCONT=1,"IP","internet.eplus.de"
OK  ATDT*99#
TIMEOUT 30
CONNECT

What i have to do to connect from the internet to the board?

Have i to set up iptables or a special route?

Thank you in advance and sorry for this networking beginner question!

Titus

Hmmmm... i think i am an idiot, worked too long this night... ;-)

I took the IP Address of the ppp0 interface to connect to the board, but
this seems to be a private address in the providers network :-(

So forget the question above...

But can give me someone a hint, how to conclude to the public address in
internet my adaptor got from provider?

Sorry and thanks,

Titus

When I was researching setting up a Sierra Compass 850 (3G) so that my
neighbour could access the his mobile broadband using the mini2440 as a
bridge to USB I had to enable iptables. 

I didn't have to finish the project because he bought a wireless router
with a USB port, so I don't know if there would be more to the job.

Good luck!

Thank you Dave!

I fear it would not work in this way. Packages initiated from the board
over 3G would be answered over NAT on the providers router from public to
private address. But packages initiated from internet can not reach the
private address, because there is no rule at providers router to which
private address it should be send.

On one public address of the provider are many private addresses. So how to
tell him for which client is it dedicated? I do not know how to apply a
proper NAT header for this to packages from outside.

It is a pity, now i am searching for providers offering public addresses or
static IPs to their 3G customers. This is not easy because i am from
Germany and the box should stay in Spain ;-)

On re-reading this I am wondering what is different about trying to connect
to a the internet via 3G and ADSL or dialup, in order to be able to access,
say a mini2440.

I run a webserver that I can access from anywhere in the world and I plan
to provide the same capability for my neighbour on 3G.

DYNDNS, at one stage, provided a free service that allows your wireless
router/ADSL modem to register your special URL when it boots up then the
internet gets routed to you.  There are many companies that provide this
service.

Hi Dave,

yes, you are right as long you get a public address from your 3G ISP. On my
ADSL network i can reach my machines too if i set up port forwarding for
telling the router which client behind has the proper daemon running.

My problem is, that most 3G providers only offer a private address on
connection (10.x.x.x).
In dyndns the public ip is shown, but how could the router of the ISP know,
to which 10.x.x.x client it should forward the connection to the public
address without setting up port forwarding dedicated to my connection?

3G internet connections are obviously only mentioned for connection to the
internet but not for connections from outside.

I think if you realize the project for your neighbour you will run in the
same trouble as me. ;-)

Some providers offer a public address bind to the simcard contract. But
this is expensive.

So i switched to plan "B" and try to set up a wireless connection the my
ADSL router. This time i did not succeed with it. Better i'll describe this
in another thread...

Titus

> I think if you realize the project for your neighbour you will run in the
> same trouble as me. ;-)

O dear! This project was a test-bed for my own setup.  And I have been
working on getting all the bits and pieces in place to achieve this goal
for the last 2 years.  As well as learn a few things about Linux.

About 6 months ago I was gong to trial this setup but he was having a
problem with "dropped connections".

I got rrdtool running and provided ping graphs to the provider and they
have only just in the last month hopefully sorted that problem out. I
wanted to provide an "alarm path" back to the www and a cellphone.  So, I
am using msmtp and eventually to a GSM to SMS gateway provider.

Looks like I had better to get on to the 3G provider to determine what my
options are.

Sounds as it is a similar project like mine ;-)

What kind of ip address is assigned to your ppp0 when connecting the 3G to
the ISP? Is it a public one or 10.x.x.x or other private one?

If it is public, which provider and where do you live?

I can find out in about a week when he returns from England.

I went on the NZ Telecom site and for $20/month I can get a static IP :(

We can only access a TelecomNZ site from our property in a rural area near
Christchurch, NZ

I assumed that they provided static IPs for people who had never heard of
DYNDNS!

Do you know why they treat a 3G connection differently than an ADSL
connection, in this regard?  Money earner for them?

Thanks, for the heads-up

Most 3G connections are intended by cell phones. They only connect to the
internet, but have no connections from internet.

Public IP addresses are rare in ipv4 and expensive to obtain. For
forwarding packages initiated from the client the provider must only setup
NAT for example with iptables, which is easily done. So he can share one
public address to many clients in the private zone like we all do at home
when connecting to internet with our PCs or whatever behind the router.

Setting up a router with these 3G connections should work easily when
installing iptables or other forwarding mechanism on the board.

In Germany it is Telecom too who offer public addresses with 3G, Vodafone i
think too.

My project (also a kind of "alarm" with local reaction and informing via
SMS. By sending a SMS to the board a internet connection should be
established to reach a web browser with further informations and
configuring options) is planned for a friend at Ibiza in Spain. I don't
know which providers offer public addresses (static or dynamic, this were
not the problem with dyndns or noip services) and what the amount for it
is. But it would be like in NZ. For 20$ you can get a ADSL too. So why 3G
when available. Like Ibiza in NZ is ADSL not available at every place,
is'nt it?

in NZ is ADSL not available at every place,
is'nt it?

If you have wires going out to the street!  And pay for an ADSL modem.  It
will probably cost me more than $1000 to run wires out to my "street".

I will be "off-grid" and wanted to be "off-landline" as well. Maybe, the
last one will not be appropriate.

More investigation is required.

Investigation!  After talking to three techs at TelecomNZ they could not
tell me if what I was trying to do was viable.

Therefore, I will have to forge on and do the tests to see if it is
possible.

A workmate suggested that maybe things could be different down here as "we
may have more IP addresses available versus Europe where they might be
managed more carefully".

Hi Dave,

oops... very expensive to get ADSL in NZ. So routing via 3G would shurely
be interesting for many users.

I hope you find a "payable" solution for the problem of private addresses.
In NZ is a greater market for connectivity via 3G, so perhaps they might
offer public addresses like your workmate says.

Good luck!

I have a long driveway!  Trenching and wire and time are the expenses.  In
the city you can get set up on ADSL much much cheaper than that.  The
modems are included in monthly plans for about $75 to $100 for several
Gigabytes.

Cheers,
Dave

Hi Dave!

I did investigations for Germany and Spain...

In German D1 (Telecom) and other provider who uses the D1 net you can take
another APN to get a (dynamic) public IP. This is no official way but it
works nice.

I tested it with a "Congstar" prepaid card and using the APN
internet.t-d1.de instead of the official one and could connect from
internet to my micro2440 with browser and ssh.

In Spain the prepaid provider "Hit" offers officially a special APN
recommended for connections with laptops for the same price as for
connections with cellular phones. This APN provides a dynamic public IP
too.

Maybe in NZ it is also be done by taking another APN. A guy from NZ has
written in another forum: "In my experience if you use the '3internet' APN
on Three you get a public IP."

Good luck!

By the way... i've compiled the no-ip client for arm because dyndns wants
money for the service, no-ip is free ;-)

Titus,

Thank you for the update and added information.  Several years ago DYNDNS
offered a free service, which I have had to log into every 3 weeks to keep
active ... waiting for the time I really wanted to use it.

I will investigate no-ip.

Cheers,
Dave