Feeds

Shocked jocks' O2 calls crossed with Brummies, now everyone's cross

No crappy crossbar to blame either

Designing a Defense for Mobile Applications

O2 customers in Birmingham have been listening in to callers in Scotland with the kind of crossed lines not usually experienced on a telephone network for decades.

The problem isn't widespread, but O2 has confirmed that customers around Birmingham have found themselves lurking on Scottish calls in an unrequested party line, able to listen in to what should be private communications without the knowledge of those making them.

Reg reader Phil Armstrong told us about the problem on Friday, having reported it to O2, but the operator wasn't able to confirm the existence of the crossed lines to us until after the weekend and even now admits to being unable to replicate the problem despite having received "a handful" of complaints.

Crossed lines get their name from the first automatic phone networks, based around a "crossbar" switch. Connections were established using a frame with two layers of parallel wires, giving the appearance of a grid when viewed from above but actually just apart from each other. A hammer at each cross point could push the wires together, making an electrical connection, and banks of such frames connected phone calls.

But two hammers pushing two intersections with only one intersection between them could create a contact at that point, a "crossed line", connecting two separate calls into a single party line.

It seems very unlikely that O2 has been running its network over networking kit approaching its centenary, entertaining as that thought is, so the problem here is obviously more digital in nature but it seems a good deal harder to track down.

Reports of similar problems on O2 go back to 2010 at least, pointing to some long-term but very rare problem that flares up every now and then. O2 say it'll update us when it can, but in the meantime anyone discussing assassination plans or dead-drop locations should stay off O2 especially if they're in Scotland. ®

HP ProLiant Gen8: Integrated lifecycle automation

More from The Register

next story
Auntie remains MYSTIFIED by that weekend BBC iPlayer and website outage
Still doing 'forensics' on the caching layer – Beeb digi wonk
Bring back error correction, say Danish 'net boffins
We don't need no steenkin' TCP/IP retransmission and the congestion it causes
NBN Co adds apartments to FTTP rollout
Commercial trial locations to go live in September
GoTenna: How does this 'magic' work?
An ideal product if you believe the Earth is flat
Samsung Z Tizen OS mobe is post-phoned – this time for good?
Russian launch for Sammy's non-droid knocked back
Telstra to KILL 2G network by end of 2016
GSM now stands for Grave-Seeking-Mobile network
Seeking LTE expert to insert small cells into BT customers' places
Is this the first step to a FON-a-like 4G network?
What FTC lawsuit? T-Mobile US touts 10GB, $100 family-of-4 plan
Folks 'could use that money for more important things' says CEO Legere
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.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Application security programs and practises
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Securing Web Applications Made Simple and Scalable
Learn how automated security testing can provide a simple and scalable way to protect your web applications.