[menog] ADSL Service Provider Bandwidth Forecasting

[Paolo Lucente]

Agree with Nigel. 

* Having already some subscribers onboard, monitor the current
  scenario. Depending on the exercise (see point below) simple
  aggregate bandwidth statistics can be also sufficient. But
  one might want to resort to something like NetFlow or sFlow.
 
* The key exercise here is to figure out an average effective
  bandwidth usage per subscriber. This can be done precisely as
  Nigel described - coarse grained - or by adding variables:
  for example because it can be expected different distribution
  of customers/offered DSL speeds across regions/areas/exchanges
  and hence know how the bandwidth value changes by changing the
  mix.

* Design bandwidth requirements around your peak hour. Set (or
  recall if already defined within the company) a threshold of
  "when to upgrade" a backbone link. Accepted thresholds are in
  the area 60-80% (matter of personal and technical details) but
  it can also vary due to organizational matters: growth rate vs
  lead time for upgrading all the components involved.

* The contention ratio in this scheme becomes a derived value.
  Or the ratio between the average effective bandwidth usage
  and the offered (nominal) capacity. Of course, a third element
  can be introduced: the guaranteed bandwidth rate - ie. adjust
  upward (or downward) the average effective bandwidth usage. In
  this case the contention ratio will be calculated between the
  guaranteed rate and the offered capacity.

* ADSL is asymmetric whereas the backhaul will likely be symmetric;
  it intuitively means the design revolves around only the greatest
  component - the downstream bandwidth.

Regards,
Paolo


On Sat, Mar 13, 2010 at 06:58:59PM +0000, Nigel Titley wrote:
> Kiyam,
> 
> >From experience in operating a fairly large ADSL user base in the UK, we
> estimate 19Kb per naive user and 38kb per "power user". We get this
> figure simply by taking the peak total bandwidth over a month and
> dividing by the number of customers. This should enable you to work out
> your bandwidth requirement given a sales forecast. We operate an
> effectively uncontended network (ie if we see congestion, we upgrade
> bandwidth).
> 
> Does this help?
> 
> Nigel
> 
> Yasser Ragab wrote:
> > Please mention how many subscribers per each packages and what is the
> > contention ratio that you use?
> > 
> >  
> > 
> > Best Regards,
> > 
> > Yasser Omar.
> > 
> > 2Connect w.l.l
> > 
> >  
> > 
> > ------------------------------------------------------------------------
> > 
> > *From:* menog-bounces at menog.net [mailto:menog-bounces at menog.net] *On
> > Behalf Of *Kiyam Kadir
> > *Sent:* Saturday, 13 March 2010 8:35 PM
> > *To:* amr.essam at tedata.net; amaged at gmail.com; menog-bounces at menog.net;
> > menog at menog.net
> > *Subject:* RE: [menog] ADSL Service Provider Bandwidth Forecasting
> > 
> >  
> > 
> > ladies and gentlemen,
> > 
> > I apologize that I didn?t make my request clear.
> > 
> >  
> > 
> > I was asking the exact mathematical formula or equation for how to
> > calculate the bandwidth requirements.
> > 
> >  
> > 
> > we have got 5 service classes ranging from 256kbps up to 3mbps
> > downstream and 128kbps up to 768kbps upstream.
> > 
> >  
> > 
> > now we have got around 10k subscribers and I would like to know what is
> > best practice in your companies like if the CIO was
> > 
> > asked how much bandwidth he/she requests the management to provide, in
> > order to give these users a reasonable contention ratio and
> > 
> > browsing experience.
> > 
> >  
> > 
> > Please do not make any comments on the given bandwidths as we are in
> > Iraq and internet resources are still difficult to get. I know that in
> > Sweden
> > 
> > people are having about 1gbps internet but yet we are in Iraq.
> > 
> >  
> > 
> >  
> > 
> >  
> > 
> >  
> > 
> >  
> > 
> > Thank you
> > 
> >  
> > 
> >  
> > 
> > Best regards,
> > 
> >  
> > 
> >  
> > 
> > Kiyam Kadir
> > 
> > Goran Net ISP
> > 
> > Business Development Manager
> > 
> > EMail: kiyam at gorannet.net <mailto:kiyam at gorannet.net>
> > 
> > Tel: 00964 (0) 770 2 666 666
> > 
> >  
> > 
> >  
> > 
> > *From:* Amr Essam [mailto:amr.essam at tedata.net]
> > *Sent:* Saturday, March 13, 2010 19:58
> > *To:* amaged at gmail.com; Kiyam Kadir; menog-bounces at menog.net;
> > menog at menog.net
> > *Subject:* Re: [menog] ADSL Service Provider Bandwidth Forecasting
> > 
> >  
> > 
> > Dears,
> > 
> > I agree with what Ahmed said, in addition that there should be a
> > targeted plan from the company to reach certain number of customers
> > planned on different locations, the plan should include customers with
> > different speeds, and upon this you start to check capacity of the
> > locations to increase the BW, usual forecasts comes out in a 3 to 5
> > years plan but I assume yearly plan for targeted number of xdsl
> > ports/clients.
> > 
> > --
> > Amr Essam
> > TE Data
> > 
> > ------------------------------------------------------------------------
> > 
> > *From: *amaged at gmail.com
> > 
> > *Date: *Sat, 13 Mar 2010 15:17:13 +0000
> > 
> > *To: *Kiyam Kadir<kiyam at gorannet.net>; <menog-bounces at menog.net>;
> > <menog at menog.net>
> > 
> > *Subject: *Re: [menog] ADSL Service Provider Bandwidth Forecasting
> > 
> >  
> > 
> > Dear Kiyam,
> > 
> > Based on reports coming from their commercial team on the subscribers
> > rate of increase during the previous year.
> > 
> > Regards,
> > Ahmed Maged
> > 
> > Sent from my BlackBerry? wireless handheld
> > 
> > ------------------------------------------------------------------------
> > 
> > *From: *"Kiyam Kadir" <kiyam at gorannet.net>
> > 
> > *Date: *Sat, 13 Mar 2010 17:17:51 +0300
> > 
> > *To: *<menog at menog.net>
> > 
> > *Subject: *[menog] ADSL Service Provider Bandwidth Forecasting
> > 
> >  
> > 
> > Dear ladies and gentlemen,
> > 
> > can anyone of you point me in the right direction on how a xDSL service
> > provider forecasts bandwidth upgrades, calculates future requirements
> > and bandwidth
> > 
> > contention ratio calculations ?
> > 
> >  
> > 
> > any help is appreciated.
> > 
> >  
> > 
> > PS: Should Philip see this email I would appreciate if he can point me
> > in the right direction to read this in his book or at least write
> > something about and put it in his book.
> > 
> > J
> > 
> >  
> > 
> > thank you in advance.
> > 
> >  
> > 
> >  
> > 
> >  
> > 
> > Thank you
> > 
> >  
> > 
> >  
> > 
> > Best regards,
> > 
> >  
> > 
> >  
> > 
> > Kiyam Kadir
> > 
> > Goran Net ISP
> > 
> > Business Development Manager
> > 
> > EMail: kiyam at gorannet.net <mailto:kiyam at gorannet.net>
> > 
> > Tel: 00964 (0) 770 2 666 666
> > 
> >  
> > 
> >  
> > 
>