Part 1 of 2:
A " Gold Master Electrician " elevated ACMA accredited licensed cabler sent us a quote recently after visiting a client's site ( residence ).
Let's leave aside the arguably excessive charges for just 2 data points ( new Cat6 run and wall socket in bedroom directly connected to a new Cat6 wall socket in the Granny Flat some 10m away )
The problem is the property has long already been connected to the NBN on FttN VDSL2 ( using the DJA0230 naturally ) – all that was needed was to remove the bridge taps plus ( i.e. additional phone sockets typically in the kitchen & back to base legacy alarm ) add the Cat6 sockets and Ethernet run.
I was, therefore, highly surprised that a so-called reputable cabler can get things so wrong mistaking FttN for HFC.
To illustrate:
FttN VDSL2 Cat3 Voice grade 2 pair copper wire:
versus
HFC Coax RG-6:
Naturally I dismissed the quote and ignored their follow up calls ( pre-COVID times )
After some delays I found someone ( Part 2 ). These good ones are hard to come by – one in 5 was truly competent, on average from personal experience.
Before that some basic info about VDSL2:
Bridge taps are common in Aussie households - typical build has a redundant phone socket in the kitchen. Chances are that if a well-equipped registered cabler were to test, one would likely get a miserable sync rate, like this:
More technical stuff in this VDSL2 PDF
For VDSL2, the length of the copper run to the Node matters very much as signals degrade with distance ( not as the crow flies kinda distance but electrical distance ).
So having a sole phone socket would result in better sync rates as opposed to several sockets. There's a good chance that the first socket or closest socket to the street would result in the best of VDSL2 signals, and this is what the customer needed - removal of all phone sockets other than the one deemed best.
VDSL2 ( NBN variant, not TransACT etc. ) in Straya:
NBN is a Layer 2 wholesaler. Their clients are RSPs who in turns have smaller RSPs and us peeps as their clients. The RSP's equipment meets NBN at any one of 121 POIs nationwide. Your premises meets the NBN's infrastucture at the first telecom socket. Fromn there, it goes to a Node and to the DSLAM hosted typically in ex-Telstra Exchanges.
The NBN network has 121 Points of Interconnect (POI’s). These are located in select telephone exchange buildings. However, not every exchange will have a one. These Points of Interconnect are located Australia wide with the following breakdown:
New South Wales: 41
Victoria: 30
Queensland: 22
Western Australia: 14
South Australia: 9
Tasmania: 2
ACT: 2
Northern Territory: 1
More:
https://www.nbnco.com.au/content/dam/nb ... t-2013.pdf
https://www.nbnco.com.au/blog/the-nbn-p ... work-works
NBN uses the Broadcom xDSL chipset in their DSLAMs. Other xDSL chipsets meant for the Asian or European markets are less likely to perform well.
https://www.theregister.com/2014/02/24/ ... l_routers/
and confirmed with a VDSL2 capable device;
( Note Bitswap and SRA - more later on mandated technical requirements for xDSL by NBN ).
So your RSP does not play a role via-a-vis you except at the POI level. Therefore, your best VDSL2 experience is complying to what NBN sets out and has nothing to do with your RSP at lower layer DSL Layer 2. Your RSP only comes in at higher layers - Layer 3 onwards for IP, authentication and so on. Once you have a decent VDSL2 sync rate with NBN's infrastructure, it'll remain constant - your RSP cannot influence this lower layer.
So this means you are free to bring your own NBN compliant VDSL2 device, not necessarily that which is imposed by your RSP.
NBN's UniDSL requirements ( Page 43 onwards )
NBN UniDSL specs
So a decent experience on VDSL2 involves:
a) Being as close as possible to the Node ( or MicroNode ) in electrical distance - Layer 1
b) Re-wiring the home to remove all legacy ADSL splitters, microfilter as well as other phone sockets ( disconnecting )- there's a cost involved but worth it if not renting - Layer 1
c) Getting a Broadcom xDSL based CPE for Layer 2 ( also known as modem router ) - there aren't many in the market that are the "all-in-one" types - in fact, having a modular approach is best - a separation of VDSL, VOIP and WiFi / Mesh Wireless.
d) On higher Layers, a decent RSP that does not skimp on CVC and provides POI charts as well as operate in a transparent & fair manner.
1)The physical layer is the first layer of the Open System Interconnection Model (OSI Model). The physical layer deals with bit-level transmission between different devices and supports electrical or mechanical interfaces connecting to the physical medium for synchronized communication.
Physical Layer includes:
-electrical /optional protocol voltage level
-the timing of voltage change
-physical data rates -maximum transmission distance
-physical connectors
-network interface cards
2)The Data-Link layer is the protocol layer in a program that handles the moving of data in and out across a physical link in a network. The Data-Link layer is layer 2 in the Open Systems Interconnect (OSI) model for a set of telecommunication protocols.
Data Link layer includes:
-media access control (MAC)
-logical link control (LLC)
-play at this layer:-PPP (point-to-point protocol), -FR (frame relay ),-Ethernet,-Token Ring,-LAPD (Link Access Procedures, D channel ),-FDDI ,
Switches are layer 2 devices except for layer 3 ones
3)The network layer is the third level of the Open Systems Interconnection Model (OSI Model) and the layer that provides data routing paths for network communication. Data is transferred in the form of packets via logical network paths in an ordered format controlled by the network layer.
Network Layer includes:
-routing of that across a logical network path is enabled here and defines packets and addressing format.
-IP (internet protocol)
-IPX (internetwork packet exchange)
-ARP(address resolution protocol)
-ICMP(Internet Control Message Protocol)
4)Transport layer is a conceptual division of methods in the layered architecture of protocols in the network stack in the Internet Protocol Suite and the Open Systems Interconnection (OSI). The protocols of the layer provide host-to-host communication services for applications.
-TCP
-UDP
-SPX
-Flow and error control
NBN = Layer 2, RSP = Layer 3, Router ( not modem ) Layer 3/4
https://www.dummies.com/programming/net ... r-network/
OSI Layers explanation attempt:
Layer 2 uses MAC addresses and is responsible for frame delivery from hop to hop.
Layer 3 uses IP addresses and is responsible for packet delivery from end to end.
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Layer 4 accomplishes this by using an addressing scheme known as Port Numbers.
Specifically, two methods of distinguishing network streams exist. They are known as the Transmission Control Protocol (TCP), or the User Datagram Protocol (UDP).
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