DDDNS.co.za

Delegated Dynamic DNS - Fail-Safe Dynamic DNS

Delegated Dynamic DNS (DDDNS) ensures that when someone uses your name, they are talking to you, or nobody at all. With this assurance you can use an ADSL or Wireless internet connection to receive mail directly for an entire small to medium enterprise, and run web services. You can also get yourself out of sticky situations.

Why | How | What | Where | When | Who

Why

Think about it:

Your ADSL or wireless line is one of the fastest and cheapest internet connections available.
Your primary reason for not running services such as direct mail delivery and a web site on your fast ADSL line is that your IP address keeps changing.
One day you discover dynamic DNS and set it up so that your name tracks your mobile IP address. You run services using your dynamic name.
But one fateful day your connection goes down. Because your connection is down, you can't update your dynamic name. (Okay, this doesn't happen often, but IF it happens, it can be a disaster.) And it does happen: on 13 September 2004, a server of ours running on an ADSL line got an IP address which had been used by a different company who used plain DDNS (no-ip.com). Our server rejected 253 mails with messages like "reject=550 5.7.1 <user@domain.co.za>... Relaying denied denied" in the space of 6 hours. They knew nothing until we phoned them and let them know there was a problem. On the bad side: those mails will have to be resent. On the good side: most of them were spam.
People continue to use your old IP address. Your web site now shows someone else's website. Your mail bounces. You fire the technical guy who set up the dynamic DNS system, even though it's the fault of the telephone company for not giving you a fixed IP address.

You have as much connection to the internet as you need - all you need to do is make sure that people know where to find you.

How does DDDNS work

How it works in one sentence: the DNS server, with the real information about where you are, is run by you at your dynamic address.

DDDNS makes your server which has a dynamic address part of the DNS infrastructure. The only way to turn your name into your IP address is to ask you - and if you are not connected, then the system fails -- as it should. Only your properly configured DNS server at your address will make it possible for your dynamic name to resolve.

In general, you want a leased line internet connection with a static IP address. A leased line is expensive, but having a static IP address allows you to run services such as mail and web servers. If you have an ADSL line, wireless connection, or a dial-up connection, you usually have a dynamic IP address (unless you paid around R120.00 extra per month for a static IP address with your dial-up). This means that every time you connect to the internet, your server appears at a different part of the internet.

An existing and well-worn technique, Dynamic DNS (DDNS, not DDDNS) allows you to use a constant name so that you can offer e-mail and web services. This works, even though your IP address changes periodically. However, there is a real risk in using Dynamic DNS for mail and web services: if your connection is interrupted, then someone else will take over your IP address. If you do not reconnect, the new holder of your IP address may lose your mail, display his web site in the place of yours, and sow confusion among your customers and friends. The system fails incorrectly and in an unsafe manner. If you live next to a construction site, or in South Africa your line can be disconnected for a few days at a time.

What do you need?

To set up a DDDNS name which can be used for a web site or direct mail delivery you need:

You need to be a network administrator or a system integrator. You have an ADSL or wireless link, or an overworked analogue or ISDN dial-up connection.

You need a Linux machine to act as your gateway to the internet. If you don't already have one, get one. (Actually, BSD is fine too, and so is Mac OS/X, but we can't help you too much with those).

You need the DDDNS software on your computer - see the software pages of the Leading Edge Business Solutions web site.
You need to choose a name under dyn.ledge.co.za, such as dddns.example.dyn.ledge.co.za.
You must decide what you want to point to this dynamic address - e.g. http://example.dddns.co.za/ or mail for users@example.dddns.co.za.
You need a DDDNS key to update your chosen subdomain. You can arrange update access for a subdomain of dyn.ledge.co.za such as example.dyn.ledge.co.za by downloading the latest DDDNS software and using the --request command line option. For an additional fee, we can register your own domain for use with the DDDNS service (e.g. wallpaperremovals.co.za).

When you receive confirmation that your domain and key request have been approved you can begin to use your dynamic name.

Application notes

Mail delivery and web site

If you use a dynamic address such as dddns.example.dyn.ledge.co.za, then you can use this to direct mail for any domain that you own, e.g. wallpaperremovals.co.za.

The DNS servers for example.dyn.ledge.co.za are run by us, and the DNS server for dddns.example.dyn.ledge.co.za is run by you at your dynamic address.

www.wallpaperremovals.co.za. IN CNAME dddns.example.dyn.ledge.co.za.
wallpaperremovals.co.za.     IN MX 10 dddns.example.dyn.ledge.co.za.

If you don't have your own domain, you can use a subdomain of dddns.co.za:

www.wallpaperremovals.dddns.co.za. IN CNAME dddns.example.dyn.ledge.co.za.
wallpaperremovals.dddns.co.za.     IN MX 10 dddns.example.dyn.ledge.co.za.

This means that mail to anymailbox@wallpaperremovals.co.za is directed to the ADSL line, and that the web server for www.wallpaperremovals.co.za is at your ADSL address.

Dial-up SMTP spooling

If your domain is wallpaperremovals.co.za, we set up spooled mail delivery like this:

wallpaperremovals.co.za.  IN  MX 10 dddns.example.dyn.ledge.co.za.
wallpaperremovals.co.za.  IN  MX 20 mailspool.ledge.co.za.

When your line is not up, mail is spooled at mailspool.ledge.co.za. When your line is connected, mail will be delivered directly to your door. When you have initiated a new connection to the internet, you trigger delivery of spooled mail using a command like fetchmail:

fetchmail --proto etrn --fetchdomains ledge.co.za mailspool.ledge.co.za

This scenario usually uses a static IP address, but DDDNS does it almost as well.

DNS chain

To get to www.wallpaperremovals.co.za, you follow the following chain:

za	handled by rain.psg.com
co.za	ns0.coza.net.za.
wallpaperremovals.co.za	handled by rock.ledge.co.za
www.wallpaperremovals.co.za	ANSWER! it's an alias for dddns.wallpaperremovals.dyn.ledge.co.za
za	handled by rain.psg.com
co.za	ns0.coza.net.za.
ledge.co.za	handled by rock.ledge.co.za
dyn.ledge.co.za	handled by rock.ledge.co.za
wallpaperremovals.dyn.ledge.co.za	handled by 165.165.5.5 (your IP address)
dddns.wallpaperremovals.dyn.ledge.co.za	ANSWER! - it's 165.165.5.5 (your IP address)

Services and prices

The following services are offered by Leading Edge Business Solutions / Intoweb in conjunction with DDDNS.co.za:

An updatable subdomain of dyn.ledge.co.za (not dddns.co.za) - free, as in beer for South African users. To obtain this free service, you must install and configure the DDDNS client software on your system, and have it send a registration request to us.

A fixed CNAME and MX record under DDDNS.co.za - free, as in beer for South African users - just ask.

1 year DNS hosting for existing domain with appropriate settings for DDDNS - R120.00+VAT.

Backup SMTP server for ADSL or wireless - R100.00+VAT per month.

Authenticated SMTP account for relaying outgoing mail - R75.00+VAT per month (if you wish to bypass your ISP's mail server). (Recommended for certain wireless providers.)

Backup SMTP server accepting ETRN for dial-up - R110.00+VAT per month.

Remote installation and configuration of DDDNS software on existing ADSL Linux gateway/firewall - R972.00+VAT once-off. Includes hosting of DDDNS.co.za subdomain and 1 year of hosting for an existing DNS domain.

On-site installation and configuration of Linux server to act as mail server and/or web server for a new or existing domain. Includes 1 year of DDDNS update access and DDDNS.co.za subdomain (see http://ledge.co.za/servers.php) - R4500.00+VAT, or R756.00+VAT per month with 1 year contract.
HTTP redirection for your domain to your DDDNS name - R120+VAT for 1 year. (e.g. redirect http://wallpaperremovals.co.za/ to http://www.wallpaperremovals.co.za/ ). You need this if you intend to receive mail for a domain and host a web site that has no "www." prefix.
Registration of new .za.net domain - "free" with 1 year DNS hosting at R120.00+VAT.
Registration of new .za.net domain - "free" with 1 year DNS hosting at R120.00+VAT.
Registration of new .co.za domain and 1 year DNS hosting - R385.00+VAT
Registration of new .com or .net domain and 1 year DNS hosting - R425.00+VAT
Vanilla Windows compatible DDNS service - you can register myname.dddns.co.za. Our dynamic DNS service is hosted in South Africa, suitable for ADSL clients running Linux or Windows. R120.00+VAT per name per year. (This service is not suitable for mail delivery, but is adequate for VPNs and certain web hosting requirements.)

Who is behind DDDNS?

DDDNS.co.za is an innovation of Leading Edge Business Solutions / Intoweb. We worked this out all by ourselves, and if you thought of it first, but neglected to patent it, it's too late now (think prior art ... and besides, software patents really stink). There's no point in patenting something like this. Dynamic IP addresses are for people who don't have deep pockets - they won't pay enough to cover the costs of patent registration, and how does a patent help anyone anyhow?