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ghell
25-03-2007, 13:50
Do they use SNMP software located in the installation disk they no doubt give out to new customers nowadays, or just QoS on their end?

I ask because someone I know, and myself, have both used NTL (under various names, when I joined it was all C&W) in Guildford since before they were giving out free 56k oh so long ago. Neither of us used any kind of installation disk because they are not needed and nobody in their right mind should install anything their ISP gives them (I don't actually know if VM/NTL gives/gave out an installation disk, I assume they do/did) and neither of us have had any problems with traffic shaping. We also have rather complicated network setups that would most likely stop SNMP getting through to VM anyway. However, QoS is done without needing to enable SNMP software on the client machine, so if they were using QoS then it would shape my traffic nomater what software I installed or OS I am using.

Also, I have found reports around that people using various linux distros (Fedora is my distro of choice) have also had no problem with traffic shaping. This leads me to believe that VM are using SNMP which must be activated by their software to monitor traffic. If this is the case, the simple solution to shaping is not to install any of their crap on any of your machines.

Does anyone have any information on how VM use traffic shaping?

handyman
25-03-2007, 13:54
Does anyone have any information on how VM use traffic shaping?

The use hardware at the headends in order to traffic shape.

ghell
25-03-2007, 14:06
That's pretty vague, do they use QoS to monitor and shape traffic in said hardware or what?

If that is the case, how come nomatter how much I torrent (legally, though I expect that makes no difference) I don't get any kind of performance hit?

Also, I'm not trying to actually bypass the shaping or something (I have read in other posts that, for example, Bill C can't post any details that would allow someone to bypass it) I'm just curious as to how they do it and why it affects some but not others.

Bill C
25-03-2007, 14:32
That's pretty vague, do they use QoS to monitor and shape traffic in said hardware or what?

If that is the case, how come nomatter how much I torrent (legally, though I expect that makes no difference) I don't get any kind of performance hit?

Also, I'm not trying to actually bypass the shaping or something (I have read in other posts that, for example, Bill C can't post any details that would allow someone to bypass it) I'm just curious as to how they do it and why it affects some but not others.There is nothing you can do at your end to bypass it. As for how it works i would be stunned if you get that sort of information on a open forum from someone who works for Virginmedia on there broadband network. :D

As for it affecting some and not others That's how it should be. Affect the heavy users at peak times and allow those that surf and play games a good QOS. Then in off peak times let the leechers leech there cotton socks off.

ghell
25-03-2007, 15:01
Yea, I didn't expect to get the information from someone who has signed a nondisclosure agreement, but I was hoping someone might happen to know, or it might be in the public domain.

I am a heavy user, so is the other person I know, and neither of us have been affected by shaping. This is why I was saying it was affecting some (insert: heavy users) but not others.

Does it say anywhere what is affected by shaping (for example bittorrent can be detected and shaped on its own), or is it the connection as a whole, ie if you use a certain amount or are in a certain percentile of the heaviest users etc, your line speed is cut. I wouldn't have thought it would be the connection as a whole because encryption is commonly used to bypass bittorrent traffic shaping, and if it was simply based on the usage (ie dumb throttling rather than shaping) encryption wouldn't make a difference.

Doesn't the modem itself contain the bandwidth setting (but refresh it from the ISP) or is that just a theoretical maximum which the ISPs shaping can still limit.

jules_mountain
18-02-2008, 16:12
It's all very simple really. You access your VM service via their cable modem which is connected to your computer. The cable modem has hardware very similar to a cut down pc with its own motherboard and OS. That means that the service provider can communicate to the modem completely independently to whatever is connected in order to, amongst other things, ascertain the traffic flowing between modem and provider. In other words they don't need you to install any software on your pc, you could connect a toaster to their modem and if it used bandwith they would still be able to monitor how much!

NotaVMFan
18-02-2008, 16:37
Yea, I didn't expect to get the information from someone who has signed a nondisclosure agreement, but I was hoping someone might happen to know, or it might be in the public domain.

I am a heavy user, so is the other person I know, and neither of us have been affected by shaping. This is why I was saying it was affecting some (insert: heavy users) but not others.

Does it say anywhere what is affected by shaping (for example bittorrent can be detected and shaped on its own), or is it the connection as a whole, ie if you use a certain amount or are in a certain percentile of the heaviest users etc, your line speed is cut. I wouldn't have thought it would be the connection as a whole because encryption is commonly used to bypass bittorrent traffic shaping, and if it was simply based on the usage (ie dumb throttling rather than shaping) encryption wouldn't make a difference.

Doesn't the modem itself contain the bandwidth setting (but refresh it from the ISP) or is that just a theoretical maximum which the ISPs shaping can still limit.


What I can make out it`s done using the Mac of the modem at the headend.

There was a manual floating about from Cisco systems detailing how the Traffic management worked.

I`ll endeavour to find the link and add it to this post...

dev
18-02-2008, 17:08
afaik VM don't do any traditional traffic shaping (all types of traffic have the same priority). Again, afaik, the STM is done at the headend and counts all traffic to/from your modem (whether it is requested by you or not). That amount is totalled up between 4pm and 9pm and if you hit the limit set for your speed, your speed is then dropped to the speed outlined in the STM rules.

VM would be stupid to rely on snmp as most firewalls would probably block it and would require running at least another process, not to mention working out if it was local traffic or not.

moaningmags
19-02-2008, 02:04
Very few people actually use the disk.
I've never used it in the 8 yrs I've been a customer and in
almost 3 years doing tech support, I always get the customer
to cancel the install disk.
So relying on the disk to traffic manage people is useless.

Stuart
19-02-2008, 02:11
What I can make out it`s done using the Mac of the modem at the headend.

There was a manual floating about from Cisco systems detailing how the Traffic management worked.

I`ll endeavour to find the link and add it to this post...

You do realise you have ressurected a thread that is nearly a year old?

---------- Post added at 01:11 ---------- Previous post was at 01:09 ----------


VM would be stupid to rely on snmp as most firewalls would probably block it and would require running at least another process, not to mention working out if it was local traffic or not.

They wouldn't need to access your computer for the snmp protocol to work. All they would need would be for the modem to answer any queries. Seeing as the modem should be connected between your firewall or router and Virgin's network, the query wouldn't even reach your firewall.

NotaVMFan
19-02-2008, 11:40
[QUOTE=Stuart C;34491780]You do realise you have ressurected a thread that is nearly a year old?

---------- Post added at 01:11 ---------- Previous post was at 01:09 ----------


You need to goto Specsavers ;)

It was Jules who ressurected the thread..

xspeedyx
19-02-2008, 12:28
I would like to see how they do this but never will hopefully they will remove it soon but I dont really get that affected by it thanks to lovely utorrent setting been tweaked

dav
19-02-2008, 13:42
I would like to see how they do this but never will hopefully they will remove it soon but I dont really get that affected by it thanks to lovely utorrent setting been tweaked


I'm intrigued.

Could you elaborate if it doesn't just involve scheduling?

jcuk
19-02-2008, 21:50
STM is brought into effect at the CMTS on the UBR. This is done at Layer 2 Level - MAC.

Traffic is monitored, Amount of bandwidth is measured between the modems MAC address and the CMTS it is connected to. Assuming this is the case, then rebooting your cable modem may enable you to connect to another CMTS and bypass the STM - but im sure VM Techs arent that stupid, so the information would be centrally logged on the UBR.

As soon as you reach the D/l Amount during the peak times, which are 4-12pm. Then STM is triggered for the corresponding MAC Address. It does not send a new config down to the cable modem, its just altered at the CMTS for that specific MAC entry.

This is my understanding, which means the only way to bypass it would be going down to the UBR location, breaking into the building, wiring upto a terminal and modifying the MAC Tables at L2.

Id doubt STM is controlled any higher than Layer 2 MAC, simply because above this, IP's are dynamically assigned, so you would end up bypassing with a simple reboot.

Thats my views anyway.

Only way your gonna get a true answer is if your working within our Networks team.

NB : Im under the impression QoS is at Layer 3, but could be wrong, someone with more experience could post up on QoS.

xspeedyx
19-02-2008, 23:45
I'm intrigued.

Could you elaborate if it doesn't just involve scheduling?

scheduling is all I meant

---------- Post added at 22:45 ---------- Previous post was at 22:45 ----------

STM is brought into effect at the CMTS on the UBR. This is done at Layer 2 Level - MAC.

Traffic is monitored, Amount of bandwidth is measured between the modems MAC address and the CMTS it is connected to. Assuming this is the case, then rebooting your cable modem may enable you to connect to another CMTS and bypass the STM - but im sure VM Techs arent that stupid, so the information would be centrally logged on the UBR.

As soon as you reach the D/l Amount during the peak times, which are 4-12pm. Then STM is triggered for the corresponding MAC Address. It does not send a new config down to the cable modem, its just altered at the CMTS for that specific MAC entry.

This is my understanding, which means the only way to bypass it would be going down to the UBR location, breaking into the building, wiring upto a terminal and modifying the MAC Tables at L2.

Id doubt STM is controlled any higher than Layer 2 MAC, simply because above this, IP's are dynamically assigned, so you would end up bypassing with a simple reboot.

Thats my views anyway.

Only way your gonna get a true answer is if your working within our Networks team.

NB : Im under the impression QoS is at Layer 3, but could be wrong, someone with more experience could post up on QoS.

STM time frame is 4-9pm not 4-12pm change a month ago.

check the STM page

TehTech
20-02-2008, 02:05
scheduling is all I meant

---------- Post added at 22:45 ---------- Previous post was at 22:45 ----------



STM time frame is 4-9pm not 4-12pm change a month ago.

check the STM page

Has it been verified yet if jcuk is indeed VM staff?
On 1 hand he SHOULD know his stuff, but has been corrected a few times now, but then again, with hardly anyone knowing what they are doing there, Im sure he fits in nicely!

jcuk
20-02-2008, 02:28
Has it been verified yet if jcuk is indeed VM staff?
On 1 hand he SHOULD know his stuff, but has been corrected a few times now, but then again, with hardly anyone knowing what they are doing there, Im sure he fits in nicely!

lol! i really shouldnt be should i :P

as i said tho mate, im not entirely sure if thats how it works, thats my theory from studying networking and cisco related stuff, dont take my word for it! ive been wrong a few times before :P

TehTech
20-02-2008, 15:10
lol! i really shouldnt be should i :P

as i said tho mate, im not entirely sure if thats how it works, thats my theory from studying networking and cisco related stuff, dont take my word for it! ive been wrong a few times before :P

Reason I asked is cos when someone has problems, a vm staff member will ask for the custmers details like MAC address & account numbers, and staff has always said to not give out info until they have been verified as being staff, just wander if you have been verified or not, cos no offence, I could say I also worked for VM and obtain peoples info such as their MAC addresses, full names, account numbers & address, so as I say, if you are actually a staff member, then I apologise, but cant be too careful these days! :)

jcuk
20-02-2008, 17:14
oh i am! didnt know i had to be verified tho :o

obviously mr staff here didnt read the 'READ THIS NOW' Threads :P

Gazjam
01-09-2009, 17:06
A friend of mine is a CCIP working with VM on the Tech.
Non disclosure agreements have indeed been signed, but its amazing what a few brandies will do.

Anyway...

Alot Netenforcer / Deep packet inspection.

VM will deny it, but its what she consulted on and indeed, oversaw the implementation of.

BenMcr
01-09-2009, 18:27
Which means what exactly? I'm pretty sure it is already know that there is Alot kit on the cable network. I think Broadbandings has mentioned it before

And congrats on being the second person on this thread to revive it after a year ;)

Robertus
01-09-2009, 19:05
When did VM start shaping?

BenMcr
01-09-2009, 19:07
On cable they haven't

Robertus
01-09-2009, 19:09
Ah cool...was thinking I'd missed something .

Ignitionnet
01-09-2009, 19:42
Blimey thread necromancy!

There are Allot Omega Series gateways on the DSL interconnects between VM and Cable and Wireless which handle the shapery there.

On the ex-ntl network there are some Allot NetEnforcers monitoring traffic, these aren't really much of a priority and it wouldn't surprise me if they were switched off now.

VM may introduce Allot AC-10000s or similar onto the cable network at some point, however if there is a project to deploy them it's not been widely done yet - VM would trial on the cable network before they deployed wholesale especially as it would require considerable work to integrate these with the CMTS so that they could be valuable for shaping traffic. That or they use them in the very popular way UPC have and upset people with a sledgehammer cracking a nut approach.

I can only apologise for my cynicism, you can imagine how many 'a friend said...' type things I see in all sorts of technology related boards. CCIPs or not that doesn't really make things more believable given that certifications appear to be handed out like penny sweets these days.

zing_deleted
01-09-2009, 19:48
Very few people actually use the disk.
I've never used it in the 8 yrs I've been a customer and in
almost 3 years doing tech support, I always get the customer
to cancel the install disk.
So relying on the disk to traffic manage people is useless.

what you should say there is not many people who know what they are doing use the disc ;)

moaningmags
01-09-2009, 22:23
Lol the disk isn't given out anymore.