DAC EPP Drop Catching Software Manual

Transcom DAC / EPP Nominet DropCatch Software

Transcom has been a business grade ISP since 1993, and continues to host some of the country’s largest corporate’s, during which time, research and development has been applied to several key areas, one being Domain acquisition.

The software you have purchased is the result of many years of testing and evaluation, and presents itself in a highly tuned script for the purpose of using the Nominet DAC and EPP servers for automatically monitoring and catching of .uk domain names, licensed owners can run multiple copies of this script on a multiple machines with a single IPS Tag. The software is not transferable and not resalable, it is also not open source, and operates under a Proprietary Licence.

The Software
The scripts operation is complex, specifically where time constraints are of the upmost importance, it has been constructed in a way where DAC connectivity has little external time loading implications, making it operate in micro seconds, even with the EPP socket hold open process.

Your IPS TAG from Nominet as well as the new EPP Account ID is hard programmed into the software, this is for licencing reasons as well as you not having to enter these every time the software is run, you can optionally chose to have your EPP password hard coded. There are no security implications here as Nominet requires you to specify a particular IP to connect, making it impossible to run from any other location, even if you licenced software was copied.

To obtain the new EPP Account ID, which is needed as an account to register newly dropped domains against, you can either call Nominet directly or run the info-<your tag>.rl supplied, once you have the account ID code please advise us.

As the Keep Alive for the EPP socket is always present during DAC operation, the transition between the DAC advising of a drop and actual EPP registration is less than 4 micro seconds, the important external factor here being the time it takes to get there, of which, is dependent on your servers proximity to the Nominet EPP server, which could be in milliseconds (not micro)

The software can of course be used to simply registering domains, as if a domain name is already available, it will bypass the DAC process and register the name immediately, so take extra care in entering the domain name without typos.

Technical Notes
The software transition speed from DAC drop to EPP registration is fractions of a millisecond, but there are external factors and DAC limitations imposed by Nominet that add to the crucial time delays in catching domains, these are :

a)     The maximum permissible DAC lookups per tag equates to 432000 lookups within a 24 hour period and a maximum of 1000 lookups a minute. Exceeding this will cause the DAC to stop lookups and imply an over use penalty, you can manually adjust this interim period when running the script, remembering that now the delay time can be entered in respect to DAC processes run as well as the hours remaining on the current drop.

As a guideline, 200000 us equates to the maximum 432000 lookups a day. If the domain you are after still hasn’t dropped and its 2200 UK time, you can use the full force of the software by setting a low delay of 7.2 hours (= 1000 hits per minute per DAC maximum) and spread it over several instances, even over several machines

b)    Your server needs to be in very close proximity to the Nominet DAC and EPP servers, with very low response times, best idea is to find a provider that is within the same AS, or even interconnect rack at Telehouse that routes to Nominet.

c)     With a 200 ms delay between DAC lookups, and server delay time, and even though the script operates at lightening speeds, this software will greatly increase your chances of catching dropped .uk domains, but, you are not the only person trying to achieve this.

You can however enhance your chances with multiple DAC accounts and / or TAGS, which is how we believe the consistent catchers are utilising the system, this may or may not be against Nominet’s terms and conditions.

Software Package

  1. run.php                                  Command line complete DAC / EPP Script
  2. config.php                             Utility to extract the new EPP Account ID
  3. licence.php                            Secret Key to run the Licenced software
  4. transcomDACEPP.pdf        This document
  5. info.php                                  Utility for obtaining your Nominet Order Code

Too use the software you will need the following :

  1. A suitable Linux server or at least shell access, located as close as possible to the Nominet DAC and EPP servers.
  2. A Nominet IPS tag (Nominet charge £100 a year)
  3. A Nominet DAC account (Nominet charge £25 a year)
  4. EPP fully configured on your IPS tag account
  5. A Nominet domain owner account ID

The script uses an encrypted licencing system for licence management, you are permitted to run as many copies as you like on multiple machines, not forgetting that DAC hits will be added together for all the shells running, and that Nominet have a policy of only 4 concurrent DAC sockets per Tag.

Copy the files directly into a Linux Shell directory, edit the file and add your epp password, registrar account ID (where names will be registered) and your licence key. The licence.key file must remain in the same directory.

Depending on your PHP setup, the script can be run in a number of ways :


./ <FILE>

php <FILE>

php5 <FILE>

Gain access to a linux shell, if you’re doing this remotely then Putty is an ideal application, log in, change to the directory when the file is, and when at the prompt simply run [prefix] <FILE>.rl. You can modify the name of the file for ease, but do not modify the or licence.key file names.

The software version will show, followed by the LSV4 licencing server authorisation checks, after which, the software will access the DAC and advise you of your limits. It willnow log you into the Nominet EPP server and report the status of your connection. If this fails, check the error reports indicated and at the end of this document for fault finding.

The DAC reports on your limits and hit availability, given over 1 minute and 24 hour intervals. If you have exceeded your limits, the DAC will report B, 123 , the numbers represent the seconds you need to wait, during which time the software will hold.

Next you will be asked for the domain name you want to catch, be aware though that if you enter a domain that isn’t currently registered, it will be registered immediately. Any Nominet uk TLD will be accepted.

Following this you have the option to enter the associated .uk TLD (not personal version), this will enable automatic registration of the .uk variant, this can be bypassed by just pressing enter, if this is done, it will produce a syntax error code at the end as no .uk domain was entered, this is normal.

You can now enter the number of DAC sessions you will run, up to 4 (commercial and corporate only) is permissible under Nominet’s access policy. These sessions can be all on the same machine, or spread over many systems and networks, but will ALL operate under the same TAG

Next enter the time period for the domain(s) to drop, normally the time left upto midnight UK time. Any value in hours is accepted, but for safe operation use 24 hrs, which will spread the allotted 432000 hits over the DAC sessions and over 24 hours. The minimum recommended time is 7.2 hours which equates to 1000 hits per minute, again, this is the maximum allowable rate before penalties.

The software will then output the delay time, per DAC session, in milliseconds. DAC hit calculation rates are shown at the end of this document and as a separate file.

After this, the Nominet responses for DAC and EPP sockets will be shown, and there will be a prompt to start the process, simply hit enter.

If the domain hasn’t dropped, the script will then run, a line of dots will show one for each dac access, and at 59 minutes a ‘*’, ‘K’ or ‘M’ will show representing the software initiating the Nominet EPP hold open and other processes determined by your version, for another 59 minutes.

When (and if) the domain drops, the script will run the EPP registration process, and if you’r lucky, you will have the domain(s), it will report the acquisition with the XML code, four common ones are programmed, others will be reported by an XML dump.

 The software will report errors during the setup process, what it can’t do is tell you if you’ve entered a typo in a domain name… If you did, it will register the domains immediately (if they are available), but, these can be deleted within a specific time frame through the Nominet web management system. Note that changes to the EPP and DAC IP’s and passwords via the management system can take longer than 24 hours to process by Nominet.

If you get errors during the EPP login process, it can be for a number of reasons:

  • wrong password entered
  • password doesn’t match up with that specified at Nominet
  • TAG must be entered in CAPITAL letters (evaluation copy only)
  • IP of your system not is allocated with Nominet
  • firewall port 700 not open

Once the DAC socket is open, it reports few errors as it doesn’t need a password, your authorisation is by your system IP, and gained only after Nominet approval and payment of the £25 + vat per year fee.

When running the software and hitting enter to start the DAC process, if it’s successful, you will see a series of dots “.” representing each DAC hit. If it fails, you will see a single “.” And a message from the DAC with your IP, advising that it’s not registered.

Should you exceed the allowable hit rate of 432000 over a 24hr period or 1000 hits per minute, the DAC will produce codes advising the status and delays until it can be used again, during which time, the DAC cannot be used.

Maximums per Hour per Min per Second ms Time us Time
DAC Hits (24 hrs) 432000 18000 300 5.00 200 200000
DAC Hits (12 hrs) 432000 36000 600 10.00 100 100000
DAC Hits (7.2 hrs) 432000 60000 1000 16.67 60 60000
Maximums per Hour per Min per Second ms Time us Time
DAC Hits (24 hrs) 432000 36000 150 2.50 400 400000
DAC Hits (12 hrs) 432000 72000 300 5.00 200 200000
DAC Hits (7.2 hrs) 432000 120000 500 8.33 120 120000
Maximums per Hour per Min per Second ms Time us Time
DAC Hits (24 hrs) 432000 54000 100 1.67 600 600000
DAC Hits (12 hrs) 432000 108000 200 3.33 300 300000
DAC Hits (7.2 hrs) 432000 180000 333 5.56 180 180000
Maximums per Hour per Min per Second ms Time us Time
DAC Hits (24 hrs) 432000 72000 75 1.25 800 800000
DAC Hits (12 hrs) 432000 144000 150 2.50 400 400000
DAC Hits (7.2 hrs) 432000 240000 250 4.17 240 240000
Running Dacs 1 2 3 4
Time ms ms ms Ms
SAFE 24 200 400 600 800
23 192 383 575 767
22 183 367 550 733
21 175 350 525 700
20 167 333 500 667
19 158 317 475 633
18 150 300 450 600
17 142 283 425 567
16 133 267 400 533
15 125 250 375 500
14 117 233 350 467
13 108 217 325 433
12 100 200 300 400
11 92 183 275 367
10 83 167 250 333
9 75 150 225 300
8 67 133 200 267
MAX 7.2 60 120 180 240
7 58 117 175 233
6 50 100 150 200
5 42 83 125 167
4 33 67 100 133
3 25 50 75 100
2 17 33 50 67
1 8 17 25 33

Good Luck !!

The Transcom Group
Copyright 1993 – 2017 Transcom – Design Technology Ltd