Monday 20 June 2011

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:

Saturday 18 June 2011

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:

Monday 13 June 2011

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.

Sunday 12 June 2011

In The Next 10 Years...

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

Saturday 11 June 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.


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.

Wednesday 8 June 2011

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
View more presentations from Zahid Ghadialy
This and other Security related presentations are available on 3G4G website.