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Month: July 2012

Techy: How secure are credit card numbers

From my “over a year ago” post about test credit and debit card numbers, I did wonder how unique/secure a credit or debit card number is. For example: If I knew “x” digits of your card number, how many possible cards would I have to guess at to hit your credit card number.

I’m basing these findings on a the most common length of credit card numbers – 16 digits.

Number of digits known Number of card possibilities if you have the “check digit” at the end Number of card possibilities if you do not have the “check digit” Observations
16 1 1 You’ve got the whole number anyway!
15 1 1 You can either calculate the missing check digit if that’s the only thing you are missing, or calculate the missing number from the check digit
14 10 100 By covering one number and the final number, you’ve just made it 10 times harder to work out your credit card number!
13 100 1,000  
12 1,000 10,000  
11 10,000 100,000  
10 100,000 1,000,000  
09 1,000,000 10,000,000  
08 10,000,000 100,000,000  
07 100,000,000 1,000,000,000,000  
06 1,000,000,000 10,000,000,000,000  
05 10,000,000,000 100,000,000,000,000  
04 100,000,000,000 1,000,000,000,000,000  
03 1,000,000,000,000 10,000,000,000,000,000  
02 10,000,000,000,000 100,000,00,000,000,000  
01 100,000,000,000,000 1,000,000,000,000,000,000 This could just be the check digit

Marking old posts

I’ve just added a piece of code from “Jem on WordPress” to flag that content older than 6 months on this blog may be inaccurate and not reflect “now” (this comes as I’ve just realised this would be my 996th [19 private, 6 drafts] post in a period of time spanning 15th of October 2001 to “today”: and that’s a long time in anybody’s book

Avoid Public Service Events – Hard Sell Unsolicited Calls

I’ve just received an unsolicited marketing call from a “Nick” (based in Birmingham, withheld number) at Public Service Events (aka and telling me details about an event they are holding on the 26th of September 2012 at The Barbican in London for “Excellence in Customer Service – Supporting Quality Public Services” and asking if we’d be interested in attending as “it’ll help benefit your company and get some of the £X million per year spending in the public sector”.

Whilst he said he ways on a deadline (“I need a decision by 3pm”), it still took 20 minutes for him to give the web site address for Public Service and then when I found the event page, I saw that they were going to charge us £895+vat each to attend (Public Sector, who according to Nick, are facing big cutbacks and are looking at finding ways to save money – “only” have to pay £395+vat each!). When I asked if we were going to have to pay the £895, he said “no, as that’s not what I’m offering”. He then went about networking, business opportunities and that it’ll be a shame to miss out on this event. 25 minutes in: “Whilst I’m not able to negotiate on the time, as I need a decision by 3pm, I can negotiate on the price. The list price is £3,000“…

Yep, £3,000! For that he was offering “delegates email address and contact details at the end [opt in only, but you can pass their details to other people to recoup the cost], flyer in the delegate bag, mention on their website [which has 30,000 public sector visitors per week] and 3 complimentary passes [which you can sell/give to other people to recoup the cost]”.

I said we didn’t have the budget and whilst we would like to attend, we couldn’t justify that price. We had a maximum budget of £500 we could spend. “But couldn’t you use a contingency or emergency money, surely you’ve put some aside?” Well, yes, for an emergency! He said he’ll be able to get it down to £2,000 (after “speaking to the events manager”) and then down to £1,500 (that’s “half price and the lowest I can go” and then to £1,000 (I feel sorry for anybody paying the full £3,000).

Note that all those prices are still above the £500 budget stated.

35 minutes in and I terminated the call.


They also operate as Public Service Review has had similar complaints about “hard sell” techniques recorded. Who Calls Me has listings for 01782630200, 01214558820, 01214563336, 01782667340, 01782633159, 01315553970 and other numbers: I think we can guess why they are now with holding their number (so you can’t search for it).

Oh – they’ve also had an ASA Complaint upheld against them.

Online Support Services – pricing compared

Here’s a quick reference list of online/cloud/SAAS support/helpdesk/CRM systems that I’m aware and pricing for 2 full time and 1 part time (10 hours month: 1 hour per day) helpdesk agent/staff with a custom URL/domain mapping (such as, knowledge base feature and, ideally, Twitter and/or Facebook interactions. Pricing is given on a “per month” payment plan.

Sirportly – £44.97/month
Unlimited staff at £14.99 each per month. Integrates with Twitter and Facebook
FreshDesk – $58/month
Unlimited staff at $19/month per full time staff and $2/per day for additional part-time agents. Unlimited Twitter accounts and multiple Facebook accounts – $59/month
Unlimited staff at $49/month per full time staff (1st one free) and $1/per hour for additional part-time agents. 2 Twitter accounts and 2 Facebook pages included by default: can add extras for a fee
Kayako Resolve OnDemand – $87/month
Unlimited staff at $29 each per month. No interactions with Twitter or Facebook
ZenDesk – $87/month
Unlimited staff at $29/month (3 staff included on $20/year “Starter” package, but no custom URL). Unlimited Twitter accounts and 2 Facebook pages
HappyFox – $99/month
Up to 5 staff (3 staff on $39/month package, but no custom URL). No interactions with Twitter or Facebook

Quicknotes: PHP Pear Modules

Just really for my memory:

To install all of the above:

pear channel-discover
pear install pearplex/PHPExcel
pear channel-discover
pear install bairwell/Bairwell_Geocoder

If you want to make your own PEAR module, consider PHIX Project