-----Original Message----- From: Juha Saarinen [mailto:juha(a)saarinen.org] Sent: Monday, 29 November 2004 12:43 p.m. To: NZ NOG Subject: [nznog] What characterises an NGN?
Wrote a bit about Telecom's NGN variant here:
http://computerworld.co.nz/news.nsf/UNID/C740B2DD592E9EDDCC256 F58000FBD33
I'm curious as to what the NOG thinks of this approach. If I look at:
http://www.iec.org/online/tutorials/next_gen/
an NGN is defined as:
"The next-generation network seamlessly blends the public switched telephone network (PSTN) and the public switched data network (PSDN), creating a single multiservice network. [...]"
Is it fair to assume that pushing CO functionality to the network edge requires an end-to-end managed solution?
There seem to be three different questions here. The first concerns what an NGN is. Once upon a time telcos ran phone networks. When they added data services, like X.25, they built separate networks to provide those services. An NGN is about putting together the necessary bits to build a network which carries voice and data over one network instead of several. The pieces tend to include an MPLS core, aggregation devices, and so on. It's tempting to say that they're standard hardware rather than the high-cost proprietary stuff telcos used in the past. But in real life there aren't many really big Junipers outside the carrier space. Anyway, the key point about it is that a telco only has one of it, which provides a range of services. There will be cases where limitations to equipment may dictate how a service can be provided, and others where the telco has some choices. "What the NOG thinks of this approach" may well be influenced by what it is an approach to. It's not clear to me, looking at the article, wha the service is that's being decribed. If the service in question is multipoint VPN's, then it seems to me to make perfect sense that customer routing information has to be shared with the carrier. Otherwise how would the carrier's provider edge routers work out where to send the customer's packets? If the service is point to point tunnelling, that's a different matter. As to whether pushing CO functionality to the network edge requires an end-to-end managed solution, I suspect the real-life answer to be "yes". But with a couple of provisos. The first is that 'end-to-end' for a carrier may not be the same as 'end-to-end' for the customers of the carrier, or for the customers of the customers of a carrier. If a telco is going to sell multiple services over a single piece of wire carrying IP packets, it does make sense for the telco to apply whatever shaping, policing etc, policies it's going to use at the customer premises. I don't immediately see how that could be done without putting a telco-administered box at the customer's premises. But if "A customer can choose to tag their own traffic to the correct QoS value, or Telecom can do this for them in the endpoints", then presumably a customer can mark their own traffic and then have Telecom's box on their premises act simply as Telecom's check that their marking matches whatever the service is supposed to be. The second proviso is really the previous question again. It's quite possible to run lower-quality services over the same, or most of the same infrastructure. I'd be very surprised to see all customers getting the same level of management regardless of what they're paying. All opinions mine only. All comments relate to telco networks in general except where I quote the original article. - Donald Neal Donald Neal |Hydrangea - warning by the Lone Technical Specialist | Ranger's colleague NGN Operations | Integration & Services Division +----------------------------------- Alcatel NZ Ltd - Telecom's network operations manager ------------------------------------------------------------------------------ "This communication, including any attachments, is confidential. If you are not the intended recipient, you should not read it - please contact me immediately, destroy it, and do not copy or use any part of this communication or disclose anything about it. Thank you. Please note that this communication does not designate an information system for the purposes of the Electronic Transactions Act 2002." ------------------------------------------------------------------------------