In reply to a post by RobertoS:

Looks remarkably like PlusNet's classifications to me .

That's the IP VPN product, nothing to do with residential or business broadband.


From: http://www.zen.co.uk/business/leased-lines-and-ipvpn...

Our IP VPN service equips your business with a private fully managed Wide Area Network (WAN) which guarantees the performance of your voice, multimedia and application traffic.

But it is to do with their MPLS network which is apparently being used at an increasing number of exchanges to provide FTTC for residential and business customers.

Are you sure it isn't applied in the same way as PlusNet's for non MPLS customers?

Edited by RobertoS (Mon 23-Sep-13 22:50:45)

In reply to a post by RobertoS:

But it is to do with their MPLS network which is apparently being used at an increasing number of exchanges to provide FTTC for residential and business customers.

Are you sure it isn't applied in the same way as PlusNet's for non MPLS customers?

This shows a fundamental misunderstanding of how this technology works and implies a blind copy/paste earlier on.

I'll be back in a bit to explain if someone hasn't already.

Err - no!

I realised, (hence the wording of my post), that the specific prioritisation methodology of MPLS will not be the same as the PlusNet one used for bog standard OR/BTW FTTC, but the existence of the classification system could very easily mean similar exists within it.

If the company has thought through the need for serious business use through MPLS, don't you think there is just the teeniest little chance they have applied an equivalent system for all their WBMC products? If PlusNet can do it, Zen certainly can.

Or do you have inside information to the contrary.

Importantly, even if this QoS system is only applied to the business VPN customers, that means it is seen as a benefit. Logically therefore, PlusNet's system should also be seen as a benefit.

Seeing as you appear to be in nit-picking critical mode, rather than system logic thinking mode, I have to say I was quite surprised at your description of Plusnet's IP Profile copying as being an essential part of QoS.

Right.

The CoS as sold on the IP VPN service is based around traffic marked at the customer premises by a local router / firewall. Most likely the Fortigate that Zen provide as a managed service doesn't 'do' MPLS but traffic is encapsulated by the first hop on the Zen network after the firewall.

When an access list or maybe even a DPI rule is matched the firewall will mark traffic with the relevant DSCP bits to mark the traffic as one of the 6 classes, this marking will then be used to assess how to handle the packet throughout the Zen MPLS network until it's popped out of the MPLS cloud at the remote side, or out of MPLS and onto the public Internet.

Note this only applies upstream as far as Internet traffic goes, the traffic coming in from the Internet will be unmarked as there's nothing there to mark it.

The Plusnet network uses Procera DPI kit to mark and police traffic in between the BT Wholesale network and their own. They require a limit on each connection so that they can properly prioritise traffic when they deliver it to end users without allowing the downstream on the connection to saturate.

CoS / QoS on an IP VPN or leased line isn't uncommon at all. It's essential to reliably running VoIP and other real time applications on links which also carry bulk traffic, however it's not the same as Plusnet's DPI system identifying traffic dynamically. QoS on a local router or firewall prevents bulk transfers from overwhelming upstream bandwidth on the local router. Note upstream - Plusnet police downstream.

They are cousins and use the same basic thing but one is Internet facing while the other is on each end of an IP VPN, is policing upstream, and the edges reside on customer sites.

For Zen to do this to Internet traffic as well they would require big expensive DPI boxes sitting between BT Wholesale and the rest of their network. They either ain't got them or if they have they are just monitoring, not marking which would be a waste as traffic stats can be obtained in many cheaper ways than a GigE capable DPI box.

Essentially thing about it this way. The Zen system is to ensure companies get a smooth experience across the Zen network in between their remote sites by controlling the priority of their traffic as it leaves their sites to ensure bulk data doesn't crowd out real time, and to ensure timely delivery of data as it traverses the Zen network.

The Plusnet model is to ensure that WBC / IPSC links don't max out and to prioritise the delivery of traffic to individual users, hence lives at the edge of the Plusnet network between themselves and BT Wholesale with a single point of marking and policing of traffic - the Zen model gets marked in one place then policed in many.

In reply to a post by RobertoS:

Seeing as you appear to be in nit-picking critical mode, rather than system logic thinking mode, I have to say I was quite surprised at your description of Plusnet's IP Profile copying as being an essential part of QoS.

How else do you propose they prevent an individual customer's link from saturating and causing serialisation if they don't police very slightly below its maximum capacity, Bob?

The rest of your post just shows you have no idea what you're talking about.

What Zen do is an out of the box feature on routers and firewalls.

What Plusnet do is a bespoke solution that relies on subscriber aware layer 7 DPI hardware snooping RADIUS transactions and interacting with bespoke reporting and customer management systems to ensure appropriate profiles are applied to appropriate customers.

EDIT: Edited to add additional detail to show how absurd the idea is that a basic DSCP marking based QoS/CoS system is in any way equivalent to a layer 7 subscriber aware traffic management system.

This is where you Google to try and find something to nitpick given it was obviously Google that gave you the Zen IP VPN stuff on which you blindly copy/pasted.

Edited by deleted (Mon 23-Sep-13 23:27:26)

Line rental and call charges look very reasonable with IDNet on a 30 day minimum term - what I did notice though was a charge of £48 if switching from LLU.

But as Zen appear to be using the new MPLS POPs for consumer-grade FTTC, thus bypassing WBMC where they have these and feeding direct from Openreach via GEA, the undoubtedly valid technical profundity of your shooting down of me may not be entirely relevant.

yes in affect it appears zen are subsidising BTw exchanges from their backhaul ones.

I wish zen had a online checker tho to confirm if on a zen or btw backhaul, as zen are very tempting for me, the BTw/BTr routing is a bit whacked and I want a static ip. The map that was published a while back on the tbb news page indicates they have a POP in my city which has me assuming my exchange will be zen backhaul.

The article has been updated today.

At the moment it is only available to existing Zen customers. Which explains why it isn't shown on their public website pages.