ADSL2/2+ Frequently Asked Questions

7402 Series

How do I know if I'm connected to ADSL2/2+ or not?
I am not getting an ADSL Sync or my ADSL sync light keeps flashing. What is wrong?
How do I know what profile I am on?
What is my ADSL2/2+ sync speed?
Can I use ADSL2/2+ Billion modems on ADSL1?
Should I use the downstream and upstream attainable rate to indicate my ADSL2/2+ maximum speed?
I want to improve sync speed, what can I do?
The Central Office/exchange only offers up to ADSL2, what Connect Mode should I set in Configuration → WAN → ADSL?
I heard that by setting the Coding Gain, I could gain faster speed. Should I do that?
Can I use line filter from my previous ADSL1 modem?
My Billion BIPAC 7402 is taking ages to get a line sync. Is my Billion modem/router broken?
I sync at 13mbit but when I do speed tests I only get about 1000kb/sec throughput on speed tests. Why am I not getting the full speeds when I download?
But I have downloaded from a local file mirror and I still get only about 1000 kb/sec with my Billion 7402. What's wrong?
Why can't I get the full 24Mbit speeds when ISPs say up to 24Mbit on their plans?
I read in one of the ADSL 2+ charts that I should be getting a certain sync speed compared to the distance from my exchange. Why am I not getting even close to that sync speed?

Q: How do I know if I'm connected to ADSL2/2+ or not?

A: Go to Configuration → WAN → ADSL, and then check out the Connect Mode.
If you are connected to ADSL 2+, please make sure the connect mode is set to ADSL 2+ auto fallback.
If you are connected to ADSL 2, then make sure it is set to ADSL 2 auto fallback.

Q: I am not getting an ADSL Sync or my ADSL sync light keeps flashing. What is wrong?

A: Check your connections and make sure your ADSL line filters are connected properly.
Make sure you have the latest firmware available at http://www.billion.com.au.
In the web configuration of the Modem, Go to Configuration → WAN → ADSL and make sure in connect mode you have the right setting.
For example if you are on an ADSL 2+ profile, make sure you have set it to ADSL 2+ auto fallback, then click on Apply and wait between 1 and 2 minutes to establish a ADSL solid sync light on your modem.

Q: How do I know what profile I am on?

A: Call your ISP and ask them whether you are on an ADSL 2+ or ADSL 2 profile.

Q: What is my ADSL2/2+ sync speed?

A: Go to Configuration → WAN → ADSL, and look out for Upstream and Downstream value.
Upstream and Downstream value shows your current ADSL2/2+ speed.

Q: Can I use ADSL2/2+ Billion modems on ADSL1?

A: Yes, you can. All ADSL2/2+ Billion modems are backward compatible with the original ADSL standard (8 mbps downstream/1 mbps upstream).

Q: Should I use the downstream and upstream attainable rate to indicate my ADSL2/2+ maximum speed?

A: No, attainable rate should not be used as the measurement of maximum speed in a true sense. The attainable rates only show the possible speed on the perfect/noiseless phone line condition, which is very unlikely to have in most houses. Very rarely will you get the attainable rate.

Q: I want to improve sync speed, what can I do?

A: There are a few things you can do to make your speed faster.
In some instances it will be faster and in some instances it won't make any difference:

• Install a central splitter. For this you will need to get an ACA certified cable installer. Typically you could gain between 1-4 mbps by just installing a central splitter in your house.
• Use line filters on all phone sockets, even on unused phone sockets. Unused phone sockets could became a passive noise generator for ADSL2/2+. ADSL2/2+ technology is very sensitive to line noise, and by doing so should improve the speed.
• Check the phone line cabling in your house as this could affect speeds, however re-cabling your house may or may not change speeds.

Q: The Central Office/exchange only offers up to ADSL2, what Connect Mode should I set in Configuration → WAN → ADSL?

A: ADSL2 autofallback will be the most appropriate Connect Mode.

Q: I heard that by setting the Coding Gain, I could gain faster speed. Should I do that?

A: It is best to leave the Coding Gain to its default value, Auto. You can tweak the coding gain settings to achieve slightly higher speeds, however this is not recommended since you will lose ADSL line sync very often and the connection will become very unstable.

Q: Can I use line filter from my previous ADSL1 modem?

A: Yes, you can.

Q: My Billion BIPAC 7402 is taking ages to get a line sync. Is my Billion modem/router broken?

A: No, that's normal. Billion 7402 series takes around 1-2 minutes to get a line sync.

Q: I sync at 13mbit but when I do speed tests I only get about 1000kb/sec throughput on speed tests. Why am I not getting the full speeds when I download?

A: Make sure you go to your local file mirror to download a good size file. To get accurate speed results try and download a 30MB file. This is the best way to test your throughputs. Speed tests on most sites are very inaccurate and are more geared towards ADSL 1 not ADSL 2 or 2+.

Q: But I have downloaded from a local file mirror and I still get only about 1000 kb/sec with my Billion 7402. What's wrong?

A: Expect to lose between 20 to 30% of your line sync when testing throughput speeds. This is due to the fact that ADSL 2/2+ copper lines are very sensitive, and the cabling in your house could also be affecting the speeds you get. When Telstra put in these copper lines, they did not have ADSL2 or 2+ in mind back then. We are already pushing the limits of speed on these copper lines. Things that can affect speeds could be if your phone line is connected near a power socket. Interference from the power socket can also affect speeds. There are many many factors that can affect ADSL 2/2+ speeds. A general rule of thumb is to knock off 20 to 30% of what an ISP says that you can achieve as far as speeds or sync. If you have fairly good line conditions you should be able to achieve throughput speeds close to the sync speeds.

Q: Why can't I get the full 24Mbit speeds when ISPs say up to 24Mbit on their plans?

A: If you want to get the full 24Mbit speed you literally need to live inside the Central Office (Exchange). It is VERY rare for anyone to attain those full speeds unless they are a stones throw from the exchange and they also need to have perfect line conditions.

Q: I read in one of the ADSL 2+ charts that I should be getting a certain sync speed compared to the distance from my exchange. Why am I not getting even close to that sync speed?

A: As mentioned before, there are several factors that determines your sync speed. As a general rule of thumb expect to take off 20 to 30% from what ISPs or charts tell you. The charts point out sync speeds in a perfect line condition which majority of Australian homes will not have. Factors such as filters, central splitter, cabling inside your house, phone lines next to a power outlet, all affect sync speeds. Sometimes the lines or the environment can be so bad that you could lose up to 50% of sync speeds. Check the "I want to improve sync speed, what can I do?" FAQ on improving sync and speeds.

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