Roaming with the IP eXchange (IPX)

From Wikipedia:

Traditionally, voice traffic interconnection between different operators has utilized the international SS7/TDM networks. However, lately the all-IP paradigm with VoIP is being rapidly introduced by different operators in various forms, such as IMS. In order to minimize the number of conversions between packet-switched voice and circuit-switched voice there is a clear need to deploy an IP based NNI (Network-to-Network Interface) and therefore an IP based interconnection network.

It is also evident that a large number of IP based services (such as Presence or IM) simply cannot be interconnected using a SS7/TDM network, further increasing the need for evolution into an IP based interconnection network.

Since the year 2000 GSM operators have been using GRX (GPRS Roaming Exchange) network for routing the IP based commercial roaming traffic between visited and home operators. Mainly 2.5G and 3G data roaming has been using GRX. GRX is a private IP network (separated from internet) consisting of multiple different GRX carriers that are connected to each other via peering points. However, GRX is limited only to GSM operator community and not all GRX's are capable of meeting the demands of real-time services.

Even though the GRX environment is not entirely suitable as a common IP network for interconnection and roaming, it offers a good starting point for the development of IPX. IPX development has been done in various GSM Association projects and working groups since 2004.

The following presentation is from LTE World Summit:

The IP Interconnect in VoLTE - Market & Technical requirements

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Benefit of 1.4GHz for Mobile Downlink

Significant benefits could flow from use of 1.4 GHz band for a supplemental mobile downlink for enhanced multi-media and broadband services, according to a study by Plum Consulting conducted for Ericsson and Qualcomm.

The study by Plum Consulting shows that using the 1.4 GHz band (i.e. 1452-1492 MHz also called 1.5 GHz by the European Parliament or the L-band by the CEPT) for terrestrial supplemental mobile downlink could generate a net present value for Europe of as much as EUR54 billion over a 10 year period.

The band is currently allocated for use by digital audio broadcasting (DAB) services in most European countries -- part of the band is allocated to terrestrial networks and part is allocated to satellite networks. None of these services have developed in the band. Rather in all countries in Europe the satellite part of the band is unused and this is also the case in the terrestrial component in most countries.

There could be up to eight times as much data being downloaded than is being uploaded in mobile networks. This imbalance is expected to grow, as rich mobile content is increasingly made available and as consumer demand continues to soar. The study found that the use of the 1.4 GHz band as a supplemental downlink band for mobile applications is shown to drastically ease capacity, to enable considerably higher user data rates, to substantially enhance the user experience and to provide significant economic benefits.

The value of releasing the 1.4 GHz band depends on whether other substitute spectrum may become available in the next 5 to 10 years. Starting from today, all countries in Europe have planned or are planning to release the 800 MHz and 2.6 GHz bands in the next two years. There is equipment available for use in both bands and services are already deployed in some countries.

Which other bands might be released over the next 10-15 years? Table 3-2 gives a number of candidate bands, ordered by the likely timing for release, including the 1.4 GHz band for completeness. In each case, we summarise the current status of the band, initiatives that suggest it might be a candidate for future release and our views on the possible timing of deployment based on the difficulty of clearing the band and the harmonisation/standardisation initiatives that would need to be undertaken before equipment would be mass produced for the band.

The white paper is embedded below for reference:

Economic study of the benefits from use of 1.4 GHz for a supplemental mobile downlink

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Explaining the Alcatel-Lucent 'lightRadio' concept

Cognitive LTE Small Cell Networks

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Home eNode B (HeNB) Architecture options

I blogged last year about the different LTE Home eNodeB architecture options, their advantages and disadvantages. Then there was the Qualcomm white paper architecture that listed these options as well. Now there is a white paper from the Femto Forum that discusses these architecture options in detail and their advantages and disadvantages. The presentation is embedded below.

HeNB (LTE Femto) Network Architecture

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In The Next 10 Years...

Verizon Wireless Promotional video...shown in the LTE World Summit 2011

Smart Meters Data and Privacy

I have in the past discussed about Smart Grids and Smart meters in this post and have mentioned some of the privacy concerns. Each electrical device has its signature which could be exploited by some rogue elements to find out if there are any people in the household or itss empty. If its empty they could take advantage by breaking in the house, etc.

Last week I heard a presentation by Onzo in a Cambridge Wireless event about Smart meters (embedded below). This was the most detailed presentation I saw that explained how this data from the smart meters

If you browse the slides you will notice that the device signatures can be used to pinpoint the type of device and in most cases also the make and model of the device. It can even point out if a device is malfunctioning or about to breakdown. The customers can get a detailed summary of the main appliances in the house and how much electricity they consume and this would be without any physical intervention in the electrical circuit in the place.

I am sure that are many positive uses of this data and can be used by various governmental agencies to learn more about people behaviour, use it for monitoring crimes (think CSI) and many other advanced services that may not yet be imaginable but the privacy concerns and worries will remain.

The presentation below starts from slide 21 that shows the data part but feel free to view the previous slides.

The First 50 Billion Data Points

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Finally, I would like to mention that most of the information I have seen about Smart meters actually only include Electric meters. I find it difficult to foresee how we would have smart meters for Gas, Water and Sewage and how the data can be exploited in a positive way.

Smart people, dumb objects, networked environments

Nice presentation explaining Internet of Things (IoT).Smart people, dumb objects, networked environments

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3GPP LTE Security Aspects

Regular readers may have realised that Security is one of my favourite topics. Having worked on Security extensively in UMTS and now in LTE, I am always keen to have a complete understanding of the Security aspects of UMTS / LTE.Here is a presentation from a 3GPP workshop held in Bangalore in May 2011.
3GPP LTESecurity Aspects

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This and other Security related presentations are available on 3G4G website.

Billing based on QoS and QoE

With Spectrum coming at a price the operators are keen to make as much money as possible out of the data packages being provided to the consumers. The operators want to stop users using over the top (OTT) services like Skype thereby losing potential revenue. They also want the users to stop using services that are offered by the operator thereby maximising their revenue.

A valid argument put forward by the operators is that 90% of the bandwidth is used by just 10% of the users. This gives them the reason to look at the packets and restrict the rogue users.

As a result they are now turning to deep packet inspection (DPI) to make sure that the users are not using the services they are being restricted to use. AllOt is one such company offering this service.

The following presentation is from the LTE World Summit:

They also have some interesting Videos on the net that have been embedded below. They give a good idea on the services being offered to the operators.

Finally, a term QoS and QoE always causes confusion. Here is a simple explanation via Dan Warren on twitter:

QoS = call gets established and I can hear what is being said, everything else is QoE

Carrier Aggregation with a difference

Click on picture to enlarge

Another one from the LTE World Summit. This is from a presentation by Ariela Zeira of Interdigital.

What is being proposed is that Carrier Aggregation can use both the licensed as well as unlicensed bands but the signalling should only happen in the licensed band to keep the operator in control.

Note that this is only proposed for Small Cells / Femtocells.

The only concern that I have with this approach is that this may cause interference with the other devices using the same band (especially ISM band). So the WiFi may not work while the LTE device is aggregating this ISM band and the same goes for bluetooth.

Comments welcome!