Cisco and Annex M ADSL in the UK

dave-lew99

dave-lew99

dave-lew99

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I'm asking here as i will get a more sensible answer than in the Networks forum.

Do Cisco support Annex M ADSL2+ in the UK yet? If not is there any indication of when?

We have some simple branch office type access that could easily be filled by an 800 series product but i'm holding off because i want it to work properly...

Failing Cisco, what alternatives are available for a similar price and features to the 871 Sec+ product?
 
From what i've seen, when Annex M isn't working properly you end up with ~16mb throughput.

If the hardware support is there and it will be extended through firmware updates then that's a viable option.
 
Could be worth looking at an Ethernet router and getting a modem to run in bridge mode, not as neat but at least you know the modem will be compatible with the service.
 
That's a good idea but i'll just get "why don't you use the current modem in bridge mode"

Problem is, the current modem is some thomson rubbish or other...

I'll leave it gestating in the back of my mind, by the time i get around to it the support may well be better... you never know
 
dave-lew99 said:
That's a good idea but i'll just get "why don't you use the current modem in bridge mode"

Problem is, the current modem is some thomson rubbish or other...

I'll leave it gestating in the back of my mind, by the time i get around to it the support may well be better... you never know
Click to expand...

Well for what its worth I know at least one person running an 877M on AAISP using AnnexM via Be wholesale.

12.4(22)T3, C870-ADVISPSERVICESK9-M

Code: 
interface ATM0
no ip address
no atm ilmi-keepalive
pvc 0 0/101 
pppoe-client dial-pool-number 1
!
dsl sync mode itu
dsl operating-mode adsl2+ 
dsl enable-training-log 
dsl bitswap both

Given that AFAIK only Be provide AnnexM lines in the UK you're probably either with Be retail or using a wholesale provider like AAISP or Fluidata so the above might be handy :)
 
Does this mean that you'll never get more than 16Mbit by default on an 877m? I've got a current sync speed of 15762kbps on my 877M also on Be - do I have to enable Annex-M explicitly to get a higher sync?

Code: 
talkbot#sh dsl interface
ATM0
Alcatel 20190 chipset information
                ATU-R (DS)                      ATU-C (US)
Modem Status:    Showtime (DMTDSL_SHOWTIME)
DSL Mode:        ITU G.992.5 (ADSL2+) Annex M
ITU STD NUM:     0x03                            0x2
Chip Vendor ID:  'STMI'                          'BDCM'
Chip Vendor Specific:  0x0000                    0x918F
Chip Vendor Country:   0x0F                      0xB5
Modem Vendor ID: 'CSCO'                          '    '
Modem Vendor Specific: 0x0000                    0x0000
Modem Vendor Country:  0xB5                      0x00
Serial Number Near:    FCZ123464EX
Serial Number Far:
Modem VerChip ID:        C196P (1) capability-enabled
DFE BOM:         DFE3.0 Annex M (3)
Capacity Used:   100%                            100%
Noise Margin:     6.0 dB                          6.0 dB
Output Power:    18.5 dBm                        12.5 dBm
Attenuation:     21.0 dB                         12.0 dB
FEC ES Errors:    0                               0
ES Errors:        1                              6172
SES Errors:       1                               5
LOSES Errors:     1                               0
UES Errors:       0                              11368
Defect Status:   None                            None
Last Fail Code:  None
Watchdog Counter: 0x9C
Watchdog Resets: 0
Selftest Result: 0x00
Subfunction:     0x00
Interrupts:      4140 (0 spurious)
PHY Access Err:  0
Activations:     1
LED Status:      ON
LED On Time:     100
LED Off Time:    100
Init FW:         init_AMR-3.0.014_no_bist.bin
Operation FW:    AMR-3.0.014.bin
FW Source:       embedded
FW Version:      3.0.14

                 DS Channel1      DS Channel0   US Channel1       US Channel0
Speed (kbps):             0            15762             0              2372
Cells:                    0       1331901721             0         932708386
Reed-Solomon EC:          0            18777             0                 0
CRC Errors:               0              170             0              9436
Header Errors:            0              166             0             11744
Total BER:                0E-0           3161E-9
Leakage Average BER:      0E-0           2905E-11
Interleave Delay:         0               60             0                21
                        ATU-R (DS)      ATU-C (US)
Bitswap:               enabled            enabled
Bitswap success:          0                   0
Bitswap failure:          0                   0

LOM Monitoring : Disabled

*edit* just read the above again, seems Annex M is working...
 
AnnexM as i understood it increases your upstream sync and in some/most cases actually decreases your downstream sync speed due to the extra tones used! This is exactly what I experience on my Be* Pro line.
 
Last edited:
Not sure what all this talk is of Annex M providing better downstream sync? Annex M simply allocates more tones for upstream than it would otherwise. Result is that you get more upstream, at the expense of downstream.
 
When I enabled Annex-M, I lost around 1500 of downstream, but my upload increase to 1.900 with a downstream of 13,000.

I've got a 877 Annex-M. I will be trialing Annex-M very soon with the WBC platform !
 
From what i've seen on the Be* forums, people previously syncing at 22mb+ with the Thomson Speedtouch thing end up at ~16mb using an 877.

Seems unclear if they're using the 877M though.

Is anyone in a position to try the original router just to see their speed?
 
My 877 generally sync`d only 2mbit slower than the Be supplied Thompson. I sync at 24 with the Thompson and around 22 with the Cisco.
 
From what we have experienced, 877's have caused some strange issues on ADSL2+ enabled lines with certain dslams, even without Annex M in use;

Slower sync speeds for a start over other hardware, but in worst case completely unstable syncs leading to a flapping connection every 10-60 seconds.

Cisco released a new ADSL firmware .bin for the 877 which was meant to bring better ADSL2+ Annex A support and similar support for certain dslams as the 877M boasts (even though that list of dslams is still tiny), however this made no improvement on a couple of test lines provided through Zen (no LLU, so actually on BT's 21CN ADSL2+ Network).

Of course it's very possible we just got unlucky with the exchange dslam's, and the slower sync speeds are due to the line profile being repeatedly fubared by resyncs, but what does annoy me is there is no way to set the dsl operating-mode to ADSL2+ Annex A only, so as not to negotiate between A and M within the ADSL2+ Space, as i'm wondering if this is causing our sync issues.

...Ethernet all the way :P

//TrX
 
TrX said:
Cisco released a new ADSL firmware .bin for the 877 which was meant to bring better ADSL2+ Annex A support and similar support for certain dslams as the 877M boasts (even though that list of dslams is still tiny), however this made no improvement on a couple of test lines provided through Zen (no LLU, so actually on BT's 21CN ADSL2+ Network).
Click to expand...

I'd expect the LLU providers to be easier in this respect as I expect they actually standardise their DSLAMs a little, BT still insist on buying from multiple manufacturers (and some are unfortunately worse than others reliability wise - I'm looking at you Fujitsu...). They do it for good reason but it's a pain, I'd have thought LLU providers are at least sticking with one manufacturer.

Then again, I'm largely avoiding DSL these days, it's a mess and fixing it doesn't appeal at the moment...
 
bigredshark said:
I'd expect the LLU providers to be easier in this respect as I expect they actually standardise their DSLAMs a little, BT still insist on buying from multiple manufacturers (and some are unfortunately worse than others reliability wise - I'm looking at you Fujitsu...). They do it for good reason but it's a pain, I'd have thought LLU providers are at least sticking with one manufacturer.

Then again, I'm largely avoiding DSL these days, it's a mess and fixing it doesn't appeal at the moment...
Click to expand...

Thanks for the input, I had an inkling that it could boil down to BT's kit, sadly some of our links need to stay on ADSL for cost purposes and we could really do to leverage the speed of ADSL2+ Annex M.

I will try and get an LLU provider circuit installed and see if that shows us 'the light'.

Ahh well, anyone blow me a fiber? ;)

//TrX
 
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