Dan Warne20 May 2007, 11:00 AM
Optus has admitted the Huawei hardware running its ADSL2+ broadband network has a fault that is preventing certain brands of modem from successfully connecting.
 Huawei: won a $100million equipment contract to supply the DSLAMs for Optus' broadband network, which has since developed a significant fault |
Optus has admitted the Huawei hardware running its ADSL2+ broadband network "does not support" certain brands of modem.
Worse, if a user tries to connect with one of the modems, it will lock up the user's port at the exchange, requiring a manual reset by Optus technical staff.
The fault is known to affect Optus' DSLAMs when current model Dynalink modems (RTA1025W, RTA1320 and RTA1045VW) as well as certain newer NetComm modems (NB9, NB6) attempt to connect. The modems are based on the Broadcom BCM6348 chipset.
The modems' maker, NetComm, claims there is nothing wrong with the modems themselves, and blames a bug in the Huawei DSLAM firmware, and in particular the line cards installed into the DSLAMs by Optus, which are based on an Infineon chipset.
NetComm (owner of both the NetComm and Dynalink modem brands in Australia) expressed frustration with the lack of resolution from Optus to date.
"Dynalink's ADSL2+ modems adhere to all relevant Australian and international specifications and standards," said NetComm's Danny Morrison.
"They were also recently tested by Telstra and listed as approved ADSL equipment, having passed IP1149 testing.
"Accordingly Dynalink's ADSL2+ modems are compatible with most DSLAMs in the market, assuming they also adhere to these standards. As was demonstrated in the recent [APC] testing at Internode, they operate particularly well with Ericsson and other Broadcom-based DSLAMs.
"A similar interoperability issue was previously identified by a major Taiwanese telco and was successfully resolved by upgrading their ADSL2+ DSLAMs to a new revision of firmware. A similar DSLAM firmware solution has been provided to Optus and it is understood that they are now planning an upgrade the affected DSLAMs, but this is likely to take several months to complete.
"An interim solution has been recommended that should prevent the issue occurring in many situations and may be used as a workaround until the affected Optus DSLAMs have been upgraded. If the DSLAM port profile or modem is set to ADSL/ADSL2 modes only (ADSL2+ is effectively disabled temporarily) then the issue may not occur.
"Whilst operating in ADSL/ADSL2 mode is likely to reduce the actual service speed attained compared to ADSL2+ this should help to provide reliability of service for customers, until the Optus DSLAM firmware upgrades are completed," Morrison concluded.
Optus sells its ADSL2+ service on a wholesale basis to a number of popular ISPs including Exetel, Westnet and Netspace (though Netspace is yet to start commissioning services based on Optus ports).
National ISP Exetel was recently forced to take the extraordinary step of suspending sales of ADSL2+ connections through Optus because of the problem.
"Exetel [has] ceased offering the NB9W (our top selling modem) pending resolution of these issues. We had also found the same problem with some other manufacturer's modems using the Broadcomm chip set," the company said in a forum posting on its website.
"We were deeply concerned that Optus would send an advice to a wholesale customer suggesting that changes they proposed to make could have the impact of rendering current customer [modems] unusable.
"Never, ever, having heard of a firmware upgrade that wasn't fully backwards compatible (from any hardware manufacturer anywhere in the world for the past 30 years) we sought clarification of what we considered to be a badly worded advice from someone who hadn't checked what they were writing.
"To date we haven't received such a clarification so the suspension of offering ADSL2 services on the Optus network remains in place. This, obviously, costs Exetel business (including yours in all probability) but Exetel's management have to make decisions based on the information provided to them or, as in this case, not provided to them," the company said.
An Optus spokesperson issued a terse statement in response to a number of questions put to the company by APC: "Optus does not support the Dynalink modem, however we do offer a range of modems that are subject to ongoing testing and approved to work on the Optus broadband network."
The company did not answer our question about whether it would provide compensation to people who had connected to Optus Broadband without being advised they could not use a Dynalink or newer NetComm modem with their connection, or to ISPs who had been selling the Broadcom-based modems.