1 Misconfigured routers: devices installed incorrectly in the first instance

2 Faulty Ethernet cards: poor quality cards that fail soon after installation, but take some time to detect

3 Broadcast storms: caused by legacy applications on legacy servers, which should have been taken out of commission

4 Unwanted protocols: many networks suffer from having had Windows terminals, printers and other peripherals installed along with extra protocols, but these are left on the network when they are no longer in regular use

5 Poor switch allocation: LAN bottlenecks caused by too many devices being allocated to run through one overloaded switch

6 Server overloading: poor ongoing maintenance of file servers causing slow spots on the network

7 Faulty devices: fundamental faults with devices attached to the network, which can be difficult to detect initially

8 SNMP management tools: the design of Simple Network Management Protocol (SNMP) is such that it can impact the performance of the devices being managed and adds to the traffic burden on the network.

9 Rogue equipment: unauthorised connection of illegitimate or inappropriate devices to the network

10 Power outage: the total failure of power supplies to networked devices

Simple Flaws and Human Error

The Top 10 reasons for Local Area Network (LAN) downtime was compiled by Chevin, a British network management company, following a poll conducted over six weeks by staff at its UK customer support centre. Chevin argues that "simple human error and lack of proper planning leading to basic faults are the two root causes of LAN downtime and inefficiencies". ®