Rumours of Juniper Router Module Glitches

Reports continue to swirl that service providers are having trouble with Juniper Networks' OC-192 Internet router modules.

The alleged problem is a packet-ordering snag when data flows enter the card. Incoming packets are directed to four processors, and when the flow is reconstructed the packets can be out of sequence, according to participants on a Juniper mailing list and sources who have contacted Network World responding to a story on the alleged problem (http://www.nwfusion.com/edge/news/2000/1109routerprob.html).

A couple of respondents say Level 3 returned modules to Juniper because the packet ordering situation was disrupting the carrier's voice-over-IP service. Level 3 says it does not comment on relationships with vendors and that its 3Voice voice-over-IP service is problem-free.

A participant on the Juniper mailing list says the situation can occur with packets of different sizes - a smaller packet can be processed faster than a larger one and incorrectly positioned in front of the larger packet when the flow is reconstructed.

The participant, whose e-mail domain is Claranet, a British ISP, says this can happen with flows exceeding 300Mbyte/sec. But flows of that nature are rare in normal ISP networks, he adds.

Juniper again says there's nothing wrong with their OC-192 modules, and that reports of Level 3 returning their blades are untrue. But the company acknowledges that its M-160 router, within which the OC-192 blades run, can reorder packets under specific conditions.

Carl Showalter, Juniper's vice president of marketing, says, however, that this is not an unusual condition and it has not impacted customer buying decisions.