Showing posts with label UMTS. Show all posts
Showing posts with label UMTS. Show all posts

Wednesday, January 10, 2018

URN Namespace and IMEI

RFC8141 - A Uniform Resource Name (URN) is a Uniform Resource Identifier (URI) [ RFC3986] that is assigned under the "urn" URI scheme and a particular URN namespace, with the intent that the URN will be a persistent, location-independent resource identifier. A URN namespace is a collection of such URNs, each of which is (1) unique, (2) assigned in a consistent and managed way, and (3) assigned according to a common definition. (https://tools.ietf.org/pdf/rfc8141.pdf).

Image courtesy of Diameter-Protocol

RFC7255 - This specification defines how the Uniform Resource Name (URN) reserved for the Global System for Mobile Communications Association (GSMA) identities and its sub-namespace for the International Mobile station Equipment Identity (IMEI) can be used as an instance-id. Its purpose is to fulfil the requirements for defining how a specific URN needs to be constructed and used in the ’+sip.instance’ Contact header field parameter for outbound behaviour. (https://www.rfc-editor.org/rfc/pdfrfc/rfc7255.txt.pdf).

RFC7254 - This specification defines a Uniform Resource Name (URN) namespace for the Global System for Mobile Communications Association (GSMA) and a Namespace Specific String (NSS) for the International Mobile station Equipment Identity (IMEI), as well as an associated parameter for the International Mobile station Equipment Identity and Software Version number (IMEISV) as per the namespace registration requirement found in RFC 3406 [ 1]. The Namespace Identifier (NID) ’gsma’ is for identities used in GSM, Universal Mobile Telecommunications System (UMTS), and Long Term Evolution (LTE) networks. The IMEI and the IMEISV are managed by the GSMA, so this NID is managed by the GSMA. (https://tools.ietf.org/pdf/rfc7254.pdf).

Tuesday, September 23, 2014

CSA - Site Survey Method/LTE-UMTS SIBs

There is a huge volume of materials and standards to be considered when undertaking study or work as an InnerCity CSA (ICCSA) expert, technician or student. However, the materials and standards referred to at my webblog aim to control the flow of such volumous information and provide instead an easy guide to seeking out the information experts, technicians or students can be exposed to when involved with ICCSA.

A highly defined smartphone etc can be offered services by a range of mobile network access systems e.g. GSM, GERAN, UTRAN, e-UTRAN etc when switched ON and actively in use or in idle mode. Access system information for LTE and UMTS are mapped in System Information Blocks (SIBs). When conducting ICCSA test measurement it is useful to identify which broadcasted SIBs contain data to help understand the survey results. Knowing the content allocated to SIBs can assist enormously in interpretation and when considering the propositions highlighted in the previous discussion thread - http://cellsiteanalysis.blogspot.co.uk/2014/08/csa-site-survey-method4cell-types.html



Below are commonly referred to LTE/UMTS SIBs. GSM and GERAN data are mapped to System Information Types that will be given in the next discsssion.

LTE System Information Blocks
***************************
SIB 1 contains PLMN identity, tracking area code, and CI of the broadcasting cell. Q-RxLevMin minimumRSRP threshold that a broadcasting cell should be measured before initial cell selection, and later for random access performed by UE. SIB Mapping Info included to inform the UE which SIBs are transmitted and how they are scheduled.

SIB 2 contains timers and constants, access barring information, UL frequency information, and UL bandwidth information.

SIB 3 contains parameters for the cell reselection procedure.

SIB 4 contains neighbour cell information for intra-frequency cell reselection.

SIB 5 contains information for interfrequency cell reselection.

SIB 6 contains information for inter-RAT cell reselection to the UTRAN.

SIB 7 contains information for inter-RAT cell reselection to the GERAN.

SIB 8 contains information for inter-RAT cell reselection to CDMA2000.

SIB 9 is used to broadcast the home eNB name (HNB name).

SIB 10 and SIB 11 can be used to broadcast warning information to subscribers (e.g. tsunami warnings).

SIB 12 assigned for Commercial Mobile Alerting System (CMAS) information usage


UMTS System Information Blocks
*****************************
SIB 1 NAS System Information, UE Timer and counter for RRC idle and connected mode

SIB 2 URA Identity

SIB 3 Parameter for Cell Selection and Cell Reselection

SIB 4 Parameter for Cell Selection and Cell Reselection in RRC connected mode

SIB 5 Parameter for configuration of Common Physical Channel (CPCH) of actual cell

SIB 6 Parameter for configuration of Common and shared Physical Channel of actual cell

SIB 7 Fast changing parameter for uplink Interference and Dynamic Persistent Level

SIB 8 Static CPCH Information of actual cell [FDD only]

SIB 9 CPCH Information of actual cell [FDD only]

SIB 10 Information for UE, which DCH is controlled by Dynamic Resource Allocation Control Procedure

SIB 11 Measurement Control Information of actual cell

SIB 12 Measurement Control Information of actual cell in RRC connected mode

SIB 13 ANSI-41 System Information

SIB 13.1 ANSI-41 RAND Information

SIB 13.2 ANSI-41 User Zone Identification

SIB 13.3 ANSI-41 Private Neighbour List

SIB 13.4 ANSI-41 Global Service Redirection

SIB 14 UL outer loop power control information for common and dedicated physical channels in RRC idle and connected mode

SIB 15 Information for UE positioning method

SIB 15.1 Information for UE GPS positioning method with Differential Global Positionig System (DGPS) correction

SIB 15.2 Information for GPS Navigation-Model

SIB 15.3 Information for GPS Almanac, ionospheric and UTC Model

SIB 15.4 Ciphering Information of SIB 15.5

SIB 15.5 Information for OTDOA UE positioning method

SIB 16 Information of Radio Bearer, transport and physical channels for UE in RRC idle or connection mode in case of Handover to UTRA

SIB 17 Fast changing parameter for the configuration of Shared Physical Channels in RRC conected mode [FDD only]

SIB 18 PLMN Identifies neighbour cells

Monday, May 05, 2014

New Book - RFPS (Radio Frequency Propagation Survey)

Joe Hoy from Forensic Analytics joins us this month at Cell Site Analysis blog to outline the purpose and content for his forthcoming book regarding  RFPS (Radio Frequency Propagation Survey).

What is your background, Joe?
"I am a telecoms engineer and trainer with 27 years of industry experience. For the last 17 years I have concentrated on telecoms training, specialising in cellular technologies particularly, for the past few years, 4G LTE.

"I have also worked extensively as a forensic cell site analyst and expert witness, contributing to many high-profile cases for either the prosecution or the defence. I’ve undertaken the work of the RFPS surveyor, capturing measurements of cellular coverage at crime scenes and other locations and have also provided extensive training for cell site analysts and RFPS engineers.




What is your current employment?
 "I now run a company called Forensic Analytics, we develop and supply software tools, such as our CSAS (Cell Site Analysis Suite) tool, to police forces and cell site analysis companies to aid them in processing call data records and RF survey results and also help them to effectively analyse, query, visualise and present that data. Traditionally, cell site analysis and their attendant forensic radio surveys were undertaken by external cell site experts, but there has been a growing trend, in the UK but also elsewhere, for law enforcement agencies to reduce the cost of forensic cell site investigations by taking some or all of the survey work ‘in house’.

Who are the potnetial readers of your book and why? 
"Many police forces now employ their own radio surveyors who undertake radio surveys for them – although there are many experienced radio engineers included in this set, in many cases the people being employed to perform these tasks are investigators and do not come from a cellular radio engineering background. Their understanding of the background of the role can therefore be somewhat limited and their technical understanding of the operation of the networks they are surveying may benefit from additional enhancement.

"In light of this, I have been asked by John Wiley Sons, the technical book publisher, to write a book that outlines the theory and practice related to the RFPS (Radio Frequency Propagation Survey) discipline within the field of cell site analysis.



Can you provide CSA blog readers with a brief outline of the content of the book
 "The first half of the book provides a reasonably simple but nonetheless detailed overview of radio theory, of basic cellular network principles and concepts and of the operation of cellular networks. The radio theory section provides an introduction to basic radio theory and offers simple explanations of the mathematical concepts that underlie radio measurements scales such as dB and dBm. The network types section is mainly focused on 3GPP network types – GSM, UMTS and LTE – but also provides an overview of the operation of other network types, such as 3GPP2 cdmaOne/CDMA2000/EV-DO, Chinese TD-SCDMA, WMIAX, WiFi, iDEN, TETRA and others.

"One of the main aims of the first half of the book is to introduce new surveyors to enough fundamental concepts to enable them to understand the meaning and significance of the measurements they will capture during surveys. It also provides details of the specific types of measurement that are captured for each network type and gives an idea of the typical range of values to be expected.


"The second half of the book focuses on forensic radio surveys; the various types of survey, the techniques employed for each survey type, the considerations and potential problems that can be encountered when surveying different types of network.


"This book is intended to be used as both a text book and as an aide memoire handbook by forensic radio survey engineers, particularly those working for official police agencies. It is not intended to act as a detailed technical reference for cell site experts or others who already understand these topics.

 
Which markets would benefit from your book?
"There is a growing market for cell site analysis in general. The UK has largely pioneered this area of forensic activity and has an experienced and mature market but the market in other parts of the world is still developing. Many countries use cell site techniques but base their conclusions purely on the proximity of a cell to a significant location. This isn’t ‘proof’ in an empirical sense and this type of cell site evidence is subject to challenge and dismissal in court. As cell site markets and techniques mature in other countries there will be a need for proper RFPS evidence and therefore, I hope, a growing market for the information provided in this book.


When will your book be available and how do readers get hold of a copy?
 "The book is due to be published by Wiley in the Autumn, but for further details please contact me at joe.hoy@forensicanalytics.co.uk. For details of our CSAS tool go to www.forensicanalytics.co.uk."

Friday, June 18, 2010

GSM Mast Installations (Density)

GSM Mast Installations (Density)
.
When planning a cellular radio network there are many aspects to consider. The matter of radio technology and their frequencies (carriers) are but two examples. A relevance to be understood from these examples relate to what services may be obtained and delivered through these carriers? GSM for basic voice and text services and W-CDMA providing high data rates for video, gaming and conferencing etc.
.
Germane and relevant to obtaining radio services are the radio access technologies needed for that - Masts and Antennas. In radio engineering terms, antennas provide the physical technology to access the services obtained in the radio coverage by use of transmitters and receivers, commonly referred to by the acronym TRXs. The Masts provide the physical location for the siting of the TRXs. An important aspect of Mast installations is knowing the potential customer numbers that will use the services obtained from them. The calculation used for the number of customers and the number of calls that can be handled by one Mast's TRXs is calculated using the Erlang formulae - the number of calls and time length of each call in an hour.
.
Generally, though, to understand how Erlang can be used to determine the number of Masts and TRXs for an area let's just say there are 50,000 potential customers for a particular area. Let us also say to retain quality of service three sectors with 2 or 4 TRXs per sector, s222 or s444 respectively, are required. Let's also indicate that it is known that:
.
=======
.
1 TRX = 3 erlang, 2 TRXs = 5 erlang, 3 TRXs = 15 erlang, 4 TRXs = 20 erlang
.
The relevant TRXs selected for this Mast installation scenario are 2 TRXs and 4 TRXs.
.
Let:
.
50,000 x 0.02 erlang, where 0.02 erlang is used per customer = **1000 erlang
.
Each sector of an s444 may carry up to 20 erlang x 3 sectors = **60 erlang
.
**1000/**60 = 16.7
.
Therefore:
.
16.7 (17) Mast installations would be needed where a configuration of TRXs s444
.
or where
.
33.4 (35) Mast installations would be needed where a configuration of TRX s222
.
================
.
Remember the above is intended only to be illustrative so that it can be used to draw inferences about Masts installations and potential user numbers based upon the density of Masts in an area. An inference, such as, why a Mast further away than Masts sited closer to where a mobile station (MS) may be located routed the text message to the MS?
.
There are a large number of issues to be considered but let us take iwo important issues to be considered are:
.
- Point-to-Area predictions for terrestrial services 30 MHz to 3000 MHz
- Point-to-Point short message service (SMS)
.
In relation to point-to-area it could be the height of buildings surrounding the MS may be a cause for a distant Mast routing a point-to-point SMS text message. Alternatively, it may be the routing of the point-to-point SMS text message from a distant Mast occurred because the MS, in the idle mode, was surrounded by Masts that were at call traffic capacity. Alternatively it could be because of a combination of both buildings and call traffic capacity.
.
Knowing matters like these are very useful when dealing cell site analysis and a reason why they are incorporated into the Core Skills Knowledge of the TrewMTE training courses:
.
GSM Cell Site Analysis Training Course
-------------------------------------------------------
.
Course One: GSM Core Skills Knowledge Course (CSA Part 1)
3-days training
.
Course Two: GSM Cell Site Analysis Course (CSA Part 2)
3-days training
.
Course Three: GSM Cell Site Analysis Course (CSA Part 3)
3-days training
.
3G Cell Site Analysis Training Course
----------------------------------------------------
Course One: 3G Core Skills Knowledge Course (CSA Part 1)
4-days training
.
Course Two: 3G Cell Site Analysis Course (CSA Part 2)
3-days training
.
Course Three: 3G Cell Site Analysis Course (CSA Part 3)
3-days training
.
SIM Card Training
-------------------------
GSM SIM Card Training Course
3-days training
.
USIM/UICC Card Training
------------------------------------
3G USIM/UICC Training Course
3-days training
.
GSM/3G Handset Examination Training
------------------------------------------------------
GSM/3G Mobile Telephone Training Course
4-days training
------------------------------------------------------
MTEB Mobile Telephone Evidence Diplomas (MTEdipl).

Friday, November 13, 2009

Mobile Phones, Security, Economy and Employment

Mobile Phones, Security, Economy and Employment
.
An article in the Telegraph on the 6th November 2009 caught my eye, titled "Inventor of mobile phones says they have become 'too complicated" are the thoughts of Martin Cooper who was th lead engineer at Motorola and made the first mobile phone call in 1973.
.
.
Echos of how complicated mobile phones can be are common views heard from many users. However, we need to make the distinction that complicated doesn't mean they are "functionally unused". As usage and personal data populates many memory areas in mobiles it is because of that "functional use" it is so important to mobile telephone examination.
.
The places where user information proliferates are places in smart phones memory that are simply not being examined by practitioners as they are being led to place too much reliance upon the machinery (reading devices) where the output is being presented parrot fashion. The machinery does not contain the high level of competence necessary to cope with all the aspects associated mobile telephone evidence. Neither, for that matter, does the machinery examine all areas of memory. The current round up of forensic readers on the market simply surf certain quarters where certain information resides in memory. Data recovered can also vary dependent upon the machinery and the machinery recovering data from some makes, models and firmware versions. It is great having tools but they really do not supercede in any shape, manner or form the ability of the knowledge and skills needed by the practitioner.
.
The above are some issues that are influencing the need for a common mobile telephone forensics standard in the UK. Other factors that require change:
.
-No longer have unnecessary separated areas between law enforcement and the independent sector.
-No longer have poorly considered policies, practices and procedures regarding mobile telephone examination and evidence because they are not fully considered by all
-No longer have various public agencies promulgating confused and diametrically opposed procedures
.
Another reason why it is important to have a single common standard approach (and a second reason why I started the mobile forensics and evidence Pathfinder Approach) is the misrespresentation regarding the status of 'mobile phone'. Inspite of a hugh array of information about wireless, radio, radio signals and their role in the creation of a mobile phone, there still remains a persistence in the forensic and evidential system in indulging the notion that mobile phones are computers. That is rather ashame because whether it is done for cheap-labelling or getting bigger budgets (more than likely) it is largely unnecessarily and willful. Computer forensics in the area of data recovery from mobile phones has made an enormous contribution to our field. But after data recovery has been performed what else does computer forensics do for mobile phone wireless, radio, radio signals etc? Nothing. That is because computer forensics is not a discipline needed to embrace wireless; computing is rather a subset of wireless communications.
.
A mobile phone is a wireless device at first instance and designed for that purpose. It has a history, decades before the hybrid (computer) was created. Mobile phones allow for instantaneous radio telecommunications to place and to enable voice and data to be communicated. The device also allows for a memory area to record exchange of information. Overall this makes wireless devices useful to the user and gives them an appeal of user-friendliness.
.
Memory, code and data can be found in many systems and devices and code and data may be subjected to computation, but in their finite existence they are not a computer. These elements are storage, protocol and information. The only area where mobile telephones are connected with computer, per se, is that they have a CPU to enable computation. But mobile phones could operate without a CPU albeit currently the experience would no doubt not be too pleasureable, and in the future where the commonly understood CPU is dispensed with.
.
Yet a further reason why practitioners tacitly admit, through their conduct, that a mobile phone is a wireless device and not a computer is through the use of radio isolation (faraday rooms, tents or bags). Faraday rooms can cost £70K of tax payers money. So why would practitioners use radio isolation if the device under test was simply a computer? Moreover, how could cell site analysis be conducted if mobile telephones were simply a computer?
.
Moreover, wireless and mobile telephones have their own legalisation, directive, standards and guidelines - none of these designate them, technically or otherwise, as computers. Indeed there is a huge number of mobile telephone departments and labs in the public sector - none of them are labelled computer.
.
Two further reasons for a common standard created by all practitioners to underpin integrity:
.
- to give courts of law guarantee about the relability of mobile telephone evidence and opinion and to allow the legal system to it jobs as opposed to trying to hoodiwink the legal system or dictate to it; the current position is high% of evidence is being pushed through on the nod without any appropriate or independent assessment or scrutiny. This is occurring because many claiming themselves to be experts the basis for which is that they have had several mobile phones or owned mobile phones or visited forums or bought a piece of equipment that reads mobile phones. This area potentially opens the door to a huge range of appeal cases costing tax payers many millions of pounds which society can ill-afford given the economic pressures on the UK for the next 6 years.
.
- there is no single coherent standard for mobile telephone examination in the UK, despite the fact that up until 2003/4 Britain led the world in mobile telephone examination and evidence which was underpinned with alot of my work that begun the programme to help law enforcement understand the technological evidence with which they were dealing. When the public sector changes took place, experience was through out of the window in favour for opening pandora's box; anyone with relatively limited experience could give mobile evidence or had a desire to train others in mobile phone evidence, they could do so; Britain's international standing has been allowed to plummet and has been dropping further ever since. This is what awaits the Olympic Games in 2012 in this country and it is important to rectify this.
.
Lastly, I point out to Government Ministers looking at this matter, you will have seen the UK MTEB Mobile Forensics Conference 25th and 26th November 2009. The point of the Pathfinder Approach is to ensure Governement has the experience available to it, not simply from Law Enforcement, but from the independent sector where 90% of knowledge and skills are developed for mobile phone examination and evidence.
.
However, there is some disappointing news that many of the Constabularies are not even sending one representative to the Conference because we are told they have no money (even where everyone knows the Conference charge is extremely low and is a not-for-profits Conference). Also, that apparently it would impact for the attending person to justify how s/he will do their work to catch up after 2-days away from the office; this is on the basis that delegation of work doesn't exist. On the back of that, numerous outsources to those Constabulary not attending, have not signed up either. This is not a case of forcing them to attend, but it highlights the glaring obvious gaps across the UK and the regional educated pot-holed thinking in the country.
.
A list of delegates of those attending Conference and speakers supporting the Pathfinder Approach can be provided to Ministers. I can confirm there are some law enforcement and public agencies attending.
.
The Economy and Employment
Maybe the NAO and/or the Competition Commissioner might start to look and to see whether the way the forensic system is divvied up stilfes proper competition in the UK and impacts on town and urban regeneration to help develop small businesses, leading to employment. For instance, what is the point of a Constabulary throwing £1-million or more at one firm when a contract for 3 years @ £100,000.00p.a. to one small firm could enable eg one-person business to take on, say, one secretary and one assistance for 3 years:
.
- £50,000.00 Principal
- £27,0000 Secretary/Assistant
- £5,000.00 for equipment
- £1800.00 for compliance training and checking
- £16,200 for office rent/business rates/phone etc etc
.
Using the £1-million as the financial basis, multiply the above idea by 10 new small businesses, 20 people newly employed, rejuvernation of local funding to locals councils and suddenly spread across the country the grass roots of growth can start without the Governement having to increase current funding levels. Certainly, if I were offered a deal like this and with my understanding of the forensics arena I could have turned one of these businesses in two years providing employment for 10 people and in 3 years employ 25 people and teach other businesses how to do it as well. I have been in this business for over 20 years. The Police have never offered me a £1 million or £500K pa contract for that matter but still seek out my advice. So why can we not put my skills to help others.
.
To assist I have a plan that can keep those new businesses up to common standard for 3 years under their contracts. Also I have a team I have identified that along with myself could spear head this project to lift it off the ground.
.
How will this help Parliament. MPs from all parties can now go back to their constituencies and offer some hope of rejuvenation and employment.
.
Hmmm....I wonder if "Dragons' Den" might be interested in this.

Sunday, June 22, 2008

GSM Mast Installations (Density)

GSM Mast Installations (Density)
.
When planning a cellular radio network there are many aspects to consider. The matter of radio technology and their frequencies (carriers) are but two examples. A relevance to be understood from these examples relate to what services may be obtained and delivered through these carriers? GSM for basic voice and text services and W-CDMA providing high data rates for video, gaming and conferencing etc.
.
Germane and relevant to obtaining radio services are the radio access technologies needed for that - Masts and Antennas. In radio engineering terms, antennas provide the physical technology to access the services obtained in the radio coverage by use of transmitters and receivers, commonly referred to by the acronym TRXs. The Masts provide the physical location for the siting of the TRXs. An important aspect of Mast installations is knowing the potential customer numbers that will use the services obtained from them. The calculation used for the number of customers and the number of calls that can be handled by one Mast's TRXs is calculated using the Erlang formulae - the number of calls and time length of each call in an hour.
.
Generally, though, to understand how Erlang can be used to determine the number of Masts and TRXs for an area let's just say there are 50,000 potential customers for a particular area. Let us also say to retain quality of service three sectors with 2 or 4 TRXs per sector, s222 or s444 respectively, are required. Let's also indicate that it is known that:
.
=======
.
1 TRX = 3 erlang, 2 TRXs = 5 erlang, 3 TRXs = 15 erlang, 4 TRXs = 20 erlang
.
The relevant TRXs selected for this Mast installation scenario are 2 TRXs and 4 TRXs.
.
Let:
.
50,000 x 0.02 erlang, where 0.02 erlang is used per customer = **1000 erlang
.
Each sector of an s444 may carry up to 20 erlang x 3 sectors = **60 erlang
.
**1000/**60 = 16.7
.
Therefore:
.
16.7 (17) Mast installations would be needed where a configuration of TRXs s444
.
or where
.
33.4 (35) Mast installations would be needed where a configuration of TRX s222
.
================
.
Remember the above is intended only to be illustrative so that it can be used to draw inferences about Masts installations and potential user numbers based upon the density of Masts in an area. An inference, such as, why a Mast further away than Masts sited closer to where a mobile station (MS) may be located routed the text message to the MS?
.
There are a large number of issues to be considered but let us take it two important issues to be considered are:
.
- Point-to-Area predictions for terrestrial services 30 MHz to 3000 MHz
- Point-to-Point short message service (SMS)
.
In relation to point-to-area it could be the height of buildings surrounding the MS may be a cause for a distant Mast routing a point-to-point SMS text message. Alternatively, it may be the routing of the point-to-point SMS text message from a distant Mast occurred because the MS, in the idle mode, was surrounded by Masts that were at call traffic capacity. Alternatively it could be because of a combination of both buildings and call traffic capacity.
.
Knowing matters like these are very useful when dealing cell site analysis and a reason why they are incorporated into the Core Skills Knowledge of the TrewMTE training courses:
.
GSM Cell Site Analysis Training Course
-------------------------------------------------------
.
Course One: GSM Core Skills Knowledge Course (CSA Part 1)
3-days training
.
Course Two: GSM Cell Site Analysis Course (CSA Part 2)
3-days training
.
Course Three: GSM Cell Site Analysis Course (CSA Part 3)
3-days training
.
3G Cell Site Analysis Training Course
----------------------------------------------------
Course One: 3G Core Skills Knowledge Course (CSA Part 1)
4-days training
.
Course Two: 3G Cell Site Analysis Course (CSA Part 2)
3-days training
.
Course Three: 3G Cell Site Analysis Course (CSA Part 3)
3-days training
.
SIM Card Training
-------------------------
GSM SIM Card Training Course
3-days training
.
USIM/UICC Card Training
------------------------------------
3G USIM/UICC Training Course
3-days training
.
GSM/3G Handset Examination Training
------------------------------------------------------
GSM/3G Mobile Telephone Training Course
4-days training
.
All courses now have credits towards the MTEB Mobile Telephone Evidence Diploma (MTEdip).