Feeds

BT overdoses on Cisco security fix

IOS patching goes awry

  • alert
  • submit to reddit

Top 5 reasons to deploy VMware with Tegile

BT restored its ADSL network to normal operation this afternoon after attempts to guard against a serious security problem overnight inadvertently disrupted the connections of a substantial minority of UK Net users this morning.

In response to a serious DoS risk affecting a wide range of Cisco routers and switches (which emerged yesterday), BT sensibly decided to upgrade the software on its core network routers to non-vulnerable versions of Cisco's IOS software. Unfortunately not everything went smoothly.

BT took a number of routers out of service overnight in order to apply patches. This left fewer routers to share the load, which shouldn't have been a problem.

However some of these routers stopped working normally, resulting in widespread packet loss which left a substantial number of ADSL users unable to get online.

Matthew Watkins of ISP IDNet explained: "We're a relatively small ISP, and we've got about 10 per cent of our customers affected with 90 per cent packet-loss on the broadband network."

"BT have given winks and nods to the recent Cisco bug. Looks like they're trying to apply filters and perform software updates to their Cisco kit."

According to Watkins, customers were having problems connecting to the Hitchin exchange. Letchworth, Cambridge and some parts of London were also affected, readers tell us, though the extent of the problem this morning remains unclear.

Mark Williamson, of telecoms reseller Gether, commented: "In trying to prevent a DoS attack they [BT] have managed to deny service to thousands of users."

This morning, BT told Williamson that all "the ADSL providers using the Central Pipe are unable to connect".

A BT spokeswoman confirmed that there were issues with BT's ADSL network this morning brought about as a side effect of "work to protect the network" against the Cisco router DoS vulnerability that emerged this week.

Although reluctant to go into too many details, she said that there was a problem with the operation of BT's ADSL network this morning which impacted a "number of service providers" until services were restored at 1:30pm this afternoon. ®

Related Stories

Cisco IOS DoS exploit released in the wild
Cisco issues network security brown alert
Power failure leads to BTo blackout
April 1 ADSL outage hits ISPs and users
UK hit by major ADSL outage

Beginner's guide to SSL certificates

More from The Register

next story
It's Big, it's Blue... it's simply FABLESS! IBM's chip-free future
Or why the reversal of globalisation ain't gonna 'appen
'Hmm, why CAN'T I run a water pipe through that rack of media servers?'
Leaving Las Vegas for Armenia kludging and Dubai dune bashing
Microsoft and Dell’s cloud in a box: Instant Azure for the data centre
A less painful way to run Microsoft’s private cloud
Facebook slurps 'paste sites' for STOLEN passwords, sprinkles on hash and salt
Zuck's ad empire DOESN'T see details in plain text. Phew!
CAGE MATCH: Microsoft, Dell open co-located bit barns in Oz
Whole new species of XaaS spawning in the antipodes
AWS pulls desktop-as-a-service from the PC
Support for PCoIP protocol means zero clients can run cloudy desktops
prev story

Whitepapers

Cloud and hybrid-cloud data protection for VMware
Learn how quick and easy it is to configure backups and perform restores for VMware environments.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Three 1TB solid state scorchers up for grabs
Big SSDs can be expensive but think big and think free because you could be the lucky winner of one of three 1TB Samsung SSD 840 EVO drives that we’re giving away worth over £300 apiece.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.