Tag Archives: NBNCo

NBNco’s FTTN – What’s in the box?

15/06/2023Australian TelcoAustralia, Australian Telecommunications History, FTTN, NBN, NBNCoNick

Note: All information contained here is sourced from: Photos provided by NBNco’s press pages, Googling part numbers from these photos, and public costing information.

This post covers the specifics and capabilities of NBNco’s FTTN solution, and is the result of some internet sleuthing.

If some of the info in here is now out of date, I’d love to know, let me know in the comments or drop me an email and I’ll update it.

FTTN in Numbers

A total of 24,544 nodes have been deployed upon completion of roll out. Each node is provisioned with 384 subscriber ports.

The hardware has 10Gbps shared between the 384 subscriber lines, equating to 208Mbps per subscriber.

Construction costs were $2.311 billion and hardware costs were $1.513 billion,

For the hardware this equates to $61,644 per node or $160 per subscriber line connected (each node is provisioned with 384 ports)

Full cost for node including hardware, construction and provisioning is $244,150 per node, which is $635 per port.

To operate the FTTN infrastructure costs $709 million per year (Made up of costs such as power, equipment servicing and spares). This equates to $28k per node per annum, or $75 per subscriber. (This does not take into account other costs such as access to the copper, transmission network, etc, just the costs to have the unit powered on the footpath.)

Overview

Inside the FTTN cabinets is a Alcatel Lucent (now Nokia) ISAM 7330 cabinet mounted on it’s side,

On the inside left of the door is a optic fibre tray where the transmission links come into the cabinet,

On the extreme left is a custom panel. It contains I/Os that are fed to the 7330, such as door open sensor, battery monitoring, AC power in, SPD and breaker.

Connection to subscriber lines happens on a frame at the end of the cabinet.

Alcatel Lucent ISAM 7330 FTTN

NBN co’s nodes are made up of Alcatel Lucent (Now Nokia) ISAM (Intelligent Services Access Manager) 7330 FTTN rack mounted it’s side.

Slot	Type	Function
1	GFC (General Facilities Card)	Power and alarm management
2	NT Slot (NANT-E Card)	Main processing and transmission
3	NTIO Slot (NDPS-C Card)	VDSL vectoring number-crunching
4	NT Slot (Free)	Optional (Unused) backup Main processing and transmission
5-12	LT (NDLT-F)	48 Port VDSL Subscriber DSLAM Interfaces

Slot numbering is just counting L to R, ALU documentation has different numbering

First up is the GFC (General Facilities Card) which handles alarm input / output, and power distribution. This connects to the custom IO panel on the far left of the cabinet, meaning the on-board IO ports aren’t all populated as it’s handled by the IO panel. (More on that later)

Next up is the first NT slot, there are two on the 7330, but in NBN’s case, only one is used; the second can be used for redundancy if one of the cards were to fail, but it seems this option has not been selected. In the first and only populated NT slot is an NANT-E Card (Combined NT Unit E) which handles transmission and main processing.

All the ISAM NANT cards support support RIPv2! But only the NANT-E card also supports BGP – Interestingly they don’t have BGP on all the NANT cards?

To the right of that is the NTIO slot, which has a NDPS-C card, which handles the vector processing for VDSL.

Brief overview of Vectoring: By adding vectoring to DSL signals allows noise on subscriber loops to be modeled, and then cancelled out with an integrated anti-phase signal matching that of the noise.

The vectoring in VDSL relies on pretty complex number crunching as the DSLAM has to constantly process the vectoring coefficients which are different for each line and can change based on the conditions of the subscriber loop etc. To do this the NDPS-C has two roles;
The NDPS-C’s Vectoring Control Entity performs non-real time calculations of vectoring coefficients and handles joining and leaving of vectored VDSL2 lines.
While the NDPS-C’s Vectoring Processor performs the real time matrix calculations based on crosstalk correction samples for the VDSL symbols collected from the subscriber lines.
The NDPS-C has a Twinax connection to every second LT Card.

After the NTIO slot is the unused NT slot.

Finally we have the 8 LT slots for line cards, which for FTTN is using the NDLT-F are 48 port line cards.

The 8 card slots allows 384 subscriber lines per node.

These are the cards which the actual subscriber lines ultimately connect to. With 10Gbps available from the NT to the LTs, means each LT card with 48 subs so 208 Mbps per subscriber max theoretical throughput.

POTS overlay is supported, this allowed VF services coexisted on the same copper during the rollout. M / X pairs are no longer added inline on new connections. (More on that on cabling).

Power & Environment

The 7330 has a 40 amp draw at -48v would mean the unit consumes 1920w

The -48v supply is provided by 2x Eltek Flatpack2 rectifiers, each providing 1Kw each.

These can be configured to provide 1Kw with redundancy to protect against the failure of one of the Flatpack2 units, or 2Kw with no redundancy, which is what is used here.

On the extreme left is a custom panel. It contains alarm I/Os that are fed to the 7330, such as door open sensor, battery monitoring, etc.

It also is the input for AC power in, surge protection device and breakers.

I did have some additional information on the batteries used and the power calculations, however NBNco’s security team have asked that this be removed.

Cabling

Incoming transmission fiber comes in on NBNco’s green ribbon fibre, which terminates on a break out tray on the left hand side wall of the cabinet. Spliced inside the tray is a duplex LC pigtail for connecting the SMF to the 7330. I don’t have the specifics on the optics used.

Subscriber lines come in via an IDC distribution frame (Quante IDS) on the right hand side end of the cabinet, accessed through a seperate door.

This frame is referred to as the CCF – Cross Connect Frame.

There are two sets of blocks on the CCF, termination of ‘X’ and ‘C’ Pairs.

‘X’ Pairs are the VF Pairs (PSTN lines) connecting to the pillar where they are jumpered back to the ‘M’ pairs back to the serving exchange,

‘C’ Pairs are the pairs containing combined VDSL & VF services to to the pillar where they are jumpered to the ‘O’ pairs which run out to the customer’s premises,

NBN Skymuster Satellite Technical Overview

24/06/2020Australian Telco, RFLTSS, NBN, NBNCo, Skymuster, SSL, SSL-1300, ViaSatNick

I’m a bit of a radio nerd & I’ve worked Satellites before, so the Skymuster / LTSS program had me curious. So here’s some nitty-gritty details on NBNCo’s Skymuster Satellite service.

The Payload

NBNco called the LTSS (Long Term Satellite service) but before launch they re-branded as “Skymuster”.

NBNco provided an Interim service called ISS (Interim Satellite Service). before the launch. IPSTAR satellite (Formerly ABG) and Optus services delivered this. Both of these had limited bandwidth and has since been largely replaced by the Skymuster / LTSS.

NBNCo contracted Space Systems / Loral, a US based satellite manufacturer to design and build the payloads. It’s based on the SSL 1300 platform.

When deployed, the payload itself measures 26 metres long, 9 metres tall and 12 metres wide, and weighs in at 6400Kg. Before deployment, in the satellite’s compressed form it fits within a 5-meter launch-vehicle fairing.

Communication to earth is via Ka-band frequencies which allows for greater density of spot beams and frequency reuse. However, capacity improvement through higher frequencies does come with some tradeoffs. Ka-band frequencies, are more susceptible to weather related conditions compared to Ku-band frequencies. Directional accuracy becomes way more important when aligning the customer dishes in Ka band also.

Direction	Min Freq	Max Freq
Earth to Satellite	27Ghz	31Ghz
Satellite to Earth	17.7Ghz	22Ghz

These emissions are within the range of the higher end software defined radio receivers. I’m curious to see what’s being transmitted, but that’s a topic for another day.

The downlink uses RH and LH circular polarisation.

The Journey

SSL assembled the satelite in California.

SSL staff packed it into a crate and loaded into the belly of an Antinov An-124 which is flown to the launch site.

There are two Skymuster Satellites, NBN-Co 1A & 1B. 1B provides infill / capacity layer for 1A but both are identical. If the 1A satellite was lost during launch / deployment, 1B could be sent up in it’s place. This is still a real risk when launching anything.

NBN-Co 1A was the first launched, riding on a Ariane-5ECA from Guiana Space Centre in French Guiana, South America. 1A launched on 30.09.2015 and 1B launched 05.10.2016 in the same configuration.

After launch to a transit orbit, the satellites had to navigate up into a geostationary orbit at ~36,000Km. This was done using it’s 4 × SPT-100 plasma thrusters, which are exactly as cool as they sound. The final navigation process took up 40% of the fuel in the satellite. Fuel is the determining factor for the expected ~15 year lifetime of the two satellites.

Once in final position SSL performed 2 months worth of tests referred to as “In Orbit Testing”. SSL then handed over operational Telemetry, Tracking and Command (TT&C) to Optus Satellite (Singtel). Optus are tasked with keeping it in it’s current position.

Customer Hardware

Ericsson manage the installation, and subcontract to Hills and Skybridge for the actual work.

Out Door Unit (ODU)

There are currently 3 Satellite Antenna options that are available for
installation, 80cm, 1.2m & 1.8m.

Narrower Ka-Band signals drops off more rapidly than Ku-Band signals. This means that aligning the Ka-Band antenna within the degrees of usable Azimuth within the Line of Sight maximises the antenna gain.

Required accuracy for each of the antennas:

80 cm: 1.4 degrees,
120 cm: 1.0 degrees
180 cm: 0.7 degrees

The below graph shows being off by 1 degree from the required accuracy, leads to -30dB drop. This translates to a power ratio of 1000, or 1/1000 of the power if correctly aligned.

The alignment process is done by the installer pointing the dish in the correct azimuth / elevation. This is based on compass / inclinometer readings, or smart phone apps. Once a rough alignment has been set, a tone-generator on the TIRA is used to align the dish.

This process requires a 16 digit installation key.

The key containing the frequency used in the installation, beam Assignment & TRIA Polarisation (The 6w version has automatic (Polarisation).

That’s entered into the installation setup page at:

http://192.168.100.1/install

TIRA’s has a built in Tone Generator which is used to “Point and Peak” the dish from the roof. The tones are:

Heartbeat 3KHz
Pointing Tones 2.5 – 3.1KHz
Peaking Tones 2.5, 2.95, 3.1 and 3.3KHz

ViaSat have videos on how the alignment process is performed.

IDU (Modem) / NTD

The modem itself is manufactured by ViaSat. I can’t find any specifics it seems to be in the RM511x line of Satellite modems.

There were some issues with a firmware update on these in 2018, that saw firmware getting rolled back.

The modems / IDU / NTDs for the ISS are not compatible with the LTSS.

There’s some nice teardown photos of a similar ViaSat modem here.

TRIA (Transmit/Receive Integrated Assembly )

The TRIA is the equivalent of a feed horn, an all in one Tx/Rx assembly. They are available in 3w and 6w variants, based on the estimated signal levels of the installation location. That’s determined by factors like high rain areas or if the subscriber is on the edge of a beam.

The 6W version has an extra F-Connector for the required DC power injection. The 6w version also has a two F-Connector gang-plate / wallplate when installed for the second RG6 run to power it.

Interestingly there’s a minimum length of cable run (8m) specified for these installations. Anything less than 8m leads to lower resistance and possible overheating.

There is a minimum length of 8m for the cable run this is very
important as it provides the right amount of cable resistance so
the modem does not get hot and over heat. Max cable run is 50m.

Configuration

Transparent Performance Enhancing Proxy (TPEP)

TPEP aka Web Acceleration, is a service offered by NBNco to spoof TCP replies, to make the handshake more efficient. It can, unsurprisingly, lead to headaches accessing services, particularly those that employ TLS.

Web Interface

http://192.168.5.100:8080/xWebGateway.cgi
user name = ADMIN and the password = operator (lower case)

Beam Selection

The installer key sets the beam, and his can be remotely changed by NBNco MAC / NOC team.

BIRRAUS have a good article explaining the spot beams available.

Educational Port

Like the other NBNco NTDs, there are multiple UNI-D ports available on the Skymuster modem allowing segregation of services.

One option that seems to be gaining traction is a dedicated port on the modem for educational use, on one of the UNI-D ports on the modem.

Educational Ports are configured to allow access for remote / distance education students.

The local state government sets pricing, speeds and data usages.

Ground Stations

There are 9 active and one standby ground stations, geographically spread across Australia, with a standby in Wolumna, NSW. The standby is capable of assuming control for any of the other ground stations.

ViaSat built the equipment and services different spot beams.

Again, BIRRAUS have this covered in their article, but here’s an extract they’ve made listing the ground stations and beams serviced.

Future

Solar Transit

Solar transits happen twice yearly when the satellite is aligned directly between the sun and Australia.

The immense solar radiation from the sun overloads the transceivers on the ground, as they’re positioned at the satelite, with the sun behind it overloading the signals.

This lasts for about 6 minutes twice yearly, and affects different ground stations and each of the satellites at different times.

Copper Cutoff

Currently the copper decommissioning does not apply to Skymuster services. This means customers with a copper POTS line, can keep it indefinitely.

This has lead to headaches with incumbent providers who had intended to decommission / sell off remote exchanges, but will be required under Universal Service Obligation to keep them active.

3rd Satellite

Due to unexpectedly large uptake of Skymuster services, NBNco had floated the possibility of launching a 3rd Satelite in 2020:

Scenario 3: Third satellite – This scenario assumes that NBN Co constructs and launches a third satellite at the end of CY20. This mitigates the need to build some fixed wireless base stations and FTTN distribution areas. The capacity of this satellite will only be partially required to meet NBN Co’s needs

Scenario 4: Third satellite in partnership – This scenario mirrors Scenario 3, but assumes that NBN Co enters into a partnership with an external party to access only the required capacity on a third satellite rather than building and owning it outright.
Source – NBNco Fixed Wireless & Satellite Review

Portable Services

Apart from spot-beam migration, there are no technical limitations preventing portable Skymuster services from becoming a service offered.

Qantas are using this to power the in-flight WiFi on their domestic fleet of 80 Boeing 737 and Airbus A330s. Though it seems that may no longer be the case.

The NBNco launched a fleet of “Road Muster” 4WDs for promotion of the services. They drive from town to town, spruiking the benefits of Skymuster.

On the roof of the 4WD is a Satellite ODU, which seems to be self / remote positioning.

Online sleuthing reveals it’s a EXPLORER 8120 manufactured by Cobham. It featuring auto-acquire, drive-away antenna system using Dynamic Pointing Correction technology. At $32k USD, it’s rather pricey, and outside the range of most grey-nomads and campers.

If a user wanted to manually position the dish, they could using a service like DishPointer.com or Wolfram Alpha. This would give a rough alignment and then the tone generator “Point and Peak” for the fine adjustment.

Layer 3 Services

Skymuster services are setup as L2 services.

NBNCo has highlighted from day 1, the option of using Layer 3 for deliver to enable deep packet inspection.

This would allow them to prioritise traffic more easily / efficiently.

Corrections

Please let me know in the comments if I’ve got anything here wrong.

NBNCo Transit Demystified

08/12/2019Australian TelcoAVC, CVC, NBN, NBNCo, TC-4, Traffic ClassNick

There’s always a lot of talk and opinion about the technologies the NBN employs, it’s effectiveness, etc.

I’ve made a conscious decision to steer clear of opinion in this blog, but there’s often talk and blame shifting between NBNco and RSPs, so I thought I’d cover how the business model works.

Because of this I thought it’d be interesting to write about how the network actually works between carriers (RSPs) and NBNco.

Physical Structure

Last Mile

The last mile in US terms, CAN in Australian Telecom lingo, is connecting the subscriber edge to the network.

NBNCo employs a few different technologies for this, depending on a number of factors;

Fiber to the Premises (Original standard – End to end fibre)
Fiber to the Node (Later addition) (Street based DLAMs for VDSL / DPUs)
Fixed Wireless (Fixed LTE)
Fiber to the Curb (Mini DSLAM powered by Modem shared between 4 subscribers and fed by fiber)
HFC – Reusing the former Optus Coax network (previously used for cable internet & pay TV)
Skymuster (Satellite service)

NBNco Backhaul

All these last mile services get consolidated and eventually end up at a local PoI – Point of Interconnect, (typically called a POP if you’re any other telco).

These are typically hosted inside exchanges, but not every exchange is an NBNco PoI, if it’s not it uses NBN Backhaul to get to the nearest PoI.

NBNco currently operates 121 PoI sites.

NBNco don’t exclusively use TEBA sites, some are hosted in NBNco “Depots”, there’s currently 10 sites not in TEBA footprints.

At the PoI

Retail Service Providers (RSPs) have to have racks inside the PoI locations, and essentially setup layer 2 cross-connects to the NBNco racks.

Once the traffic is on the RSP network, it’s the RSP’s responsibility to carry it where it needs to go, via their own network / backhaul.

Billing and Metering

Of course, if NBNco is handing off the pipes of customer traffic off to each RSP they need a way to charge the RSPs for this, this is handled by two elements – CVCs equating to the bandwidth at the PoI and AVCs equating to a fixed standing charge per connection monthly.

CVC – Connectivity Virtual Circuit

At the PoI the connection between the NBNco rack and the RSP rack is metered over a CVC – Connectivity Virtual Circuit.

This is shared across all users of that RSP at that PoI.

Let’s say I’m an RSP and I’ve purchased a 1Mbps CVC shared across my 1,000 customers at that PoI, the customers aren’t going to have a good experience.

Of course, CVC bandwidth isn’t free, previously NBNco charged on average $15.25/Mbps.

This had the effect of ensuring each RSP had just enough CVC bandwidth for their customers, but this led to some customers having a poor experience on switching to NBNco as they found their speeds dropped due to not enough CVC bandwidth at the PoI for that RSP.

In June 2017 NBNco announced a change to the pricing structure to try and encourage RSPs to buy more CVC bandwidth to ensure customers speeds weren’t bottlenecked at the CVC.

The new pricing structure makes it more financially attractive to buy more CVC bandwidth based on how many active connections (AVCs) an RSP has in place.

NBNco now charges $17.50 per symmetrical Mbps for each traffic class. (More on traffic classes later)

This means at each PoI the RSP must have a pool of CVC bandwidth large enough to meet the needs of all the customers connections (AVCs) bandwidth needs at that PoI.

AVC – Access Virtual Circuit

NBNco charges AVC fees based on the speed tier the end user will have and the traffic class (QoS) the service has applied.

(This speed tier is regardless of if the RSP has the CVC bandwidth to support this)

Introducing NNIs

NBNco acknolged in Jul 2018 that for some carriers (RSPs) having presence in 121 sites puts up a large barrier to entry.

To counteract this they introduced Network-Network Interface (NNI).

Imagine you’re operating an RSP with a footprint in capital cities and PoI / CVCs in populated areas, you can’t serve customers in remote areas without having a presence at their local NBNco PoI location and buying CVC bandwidth for that location – It just wouldn’t stack up financially.

NBNco introduced the NNI product to essentially backhaul the traffic from these customers to the nearest PoI their RSP is at and share the CVC bandwidth at that PoI.

Under the Hood with NBN FTTC Hardware (DPUs)

09/11/2019Australian TelcoDPU, FTTC, NBN, NBNCoNick

NBNco’s FTTC technology is accounting for a larger and larger share of the access network mix as the rollout nears completion, but let’s take a look at the hardware doing the heavy lifting.

I won’t go into the fiber network build NBNco are using (Squids, etc) in this post, we’ll just focus on the DSLAM that lives in the pit outside your house, or in NBN parlance – DPU or Distribution Point Unit.

In short, this is a 4 port DSLAM, fed by a fiber service and reverse powered.

The unit itself is waterproof, allowing it to live in the pit outside a customer premises, for FTTC deployments it’s common for every second P3 pit to contain a DPU (each pit typically feeds two premises).

There’s 4 copper tails for connecting in each of the 4 copper pairs to feed 4 premises. The copper run is typically less than 100m and is pretty easy to work out – Pace the distance from your first telephone outlet (TO) to your nearest pit, and there’s a 50% chance that’s the length of your cable run. Because of the short run of cable it’s a lot less to go wrong in the CAN, the only joint on the pair being the one on the DPU itself and anything inside the demarcac.

The DPU is powered by the customer’s modem via a reverse power feed, this means NBNco don’t have to worry about powering the unit, something on FTTN cabinets has been a maintenance headache due to battery backup maintenance.

The lead in cable to the customer premises is joined to the DPU via a “Snot Box”.

Unfortunately due to the enclosures being water tight and sealed, they don’t have the best thermal management. It’s not uncommon for them to reach 50+ degrees C in the field, which leads to a high failure rate, especially during summer.

NetComm Wireless / Casa NDD-4100

In 2016 NetComm Wireless (Now owned by Casa Systems) signed an agreement with NBNco to provide Fiber to the Distribution Point (FTTdp) Distribution Point Unit (DPU) equipment to NBNco for the launch in 2018, using their NetComm NDD-4100 units.

The unit has 4 ports for customer connections over a VDSL G.9923 interface, with reverse power feed, meaning the unit is fed by the CPE.

For backhaul the unit has GPON G.984 interface.