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Old 29-01-2013, 18:19   #3330
Chrysalis
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Re: Think Broadband Ping Monitor Results (POST YOURS)

Quote:
Originally Posted by Sephiroth View Post
AFAIK, VM used TAS (Ack Suppression) in the form of Turbodox. I don't know the poosition now, but I imagine it could still be in use. Here is a supporting quote from Mark Wilkin in September 2010:

We've just released the new 12.01 firmware update for VM300 Cable Modems across our network.

The new firmware was tested over the past 8 weeks with 2000 customers including volunteers from this forum and we've seen no significant issues in testing.

The new firmware enables 100Mbps throughput for our forthcoming 100Mbps service and is also designed to improve upstream stability and throughput. It also turns back on the TDOX feature that was switched off in July with the 10.12 firmware, due to a bug affecting performance.


BTW, note VM saying that the VMNG300 was fit for 100 meg.
Qas are you sure large rwins reduce ack overhead? The only thing I have found that affects ack overhead is delayed acks, nagle algorithm and adjusting mtu(mss) size. Whilst boosting rwin allows higher throughput the ack throughput goes up with it. Also supressing acks isnt without consequence, its good for certian bulk downloads but bad for small packets. sacks also sends the same amount of acks, the difference sacks offers is just how recovery works if packets are dropped.

---------- Post added at 18:19 ---------- Previous post was at 18:19 ----------

Quote:
Originally Posted by qasdfdsaq View Post
As far as I know 12Mbit upload is never implemented before 2-channel bonded upstream is implemented. In other words, 40Mbps upload channels are a prerequisite before anybody gets 12Mb
Thats what I thought until my neighbour was put on 12mbit without bonding and I seen reports on tbb with the same.
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