Feeds

Aftershocks of undersea cable outage hit UK ISPs

DDoS attack theory debunked

  • alert
  • submit to reddit

The Essential Guide to IT Transformation

A damaged undersea transatlantic cable led to the failure of other Internet systems which resulted in serious problems for many UK Net users this week.

Damage to a cable somewhere off the French coast at around 4pm on Tuesday afternoon caused havoc for Net and phone users in the UK.

BT has confirmed that some of its voice services were hit by the outage, while NTL blamed the cable problem for downing its Net service - including web browsing, email, FTP and newsgroups - for around eight hours until around 1am on Wednesday morning.

An NTL spokeswoman told The Register that because of knock-on effects users still experienced problems when traffic was re-routed (see NTL status page here).

Put under extra pressure, NTL's DNS servers failed, she said. That meant users were unable to log onto Web sites using their host name, even though the sites were reachable to users who knew their IP address. Email and other services were hosed for the same reason.

NTL's users were the worst affected,but we understand blueyonder, BT, Freeserve, Pipex and Nildram users all experienced problems to a lesser or greater extent. Telewest, which continues to investigate the problem, has confirmed its blueyonder subscribers also experienced difficulties accessing email and personal webspace for around four hours on Tuesday night.

A Telewest representative commented: "While the problems were ongoing we saw a massive increase in DNS look-ups for Zone Alarm, which seemed to be a side effect of the cable damage and some networks being down."

Behaviour like this has led to a theory that Zone Alarms was been attacked in a DDoS attack routed through insecure UK ISP networks.

But this theory fails to stack up, according to Neil Barrett, technical director at security consultancy Information Risk Management (IRM), and an expert on computer forensics,.

"Name server lookups were slow but in other aspects the Internet was performing normally. This just didn't have the look and feel of a DDoS attack," he said. ®

Related Stories

Damaged undersea cable blamed for UK Net problems
WorldPay recovers from massive attack

The Essential Guide to IT Transformation

More from The Register

next story
Trying to sell your house? It'd better have KILLER mobile coverage
More NB than transport links to next-gen buyers - study
iWallet: No BONKING PLEASE, we're Apple
BLE-ding iPhones, not NFC bonkers, will drive trend - marketeers
Auntie remains MYSTIFIED by that weekend BBC iPlayer and website outage
Still doing 'forensics' on the caching layer – Beeb digi wonk
Scotland's BIG question: Will independence cost me my broadband?
They can take our lives, but they'll never take our SPECTRUM
NBN Co adds apartments to FTTP rollout
Commercial trial locations to go live in September
Samsung Z Tizen OS mobe is post-phoned – this time for good?
Russian launch for Sammy's non-droid knocked back
Speak your brains on SIGNAL-FREE mobile comms
Readers chat to the pair who flog the tech
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.
The Essential Guide to IT Transformation
ServiceNow discusses three IT transformations that can help CIO's automate IT services to transform IT and the enterprise.
Maximize storage efficiency across the enterprise
The HP StoreOnce backup solution offers highly flexible, centrally managed, and highly efficient data protection for any enterprise.