EPC: A new core network for the new LTE radio technology

Many new transmission facilities to the cellular towers are visible part of the LTE structure.


The second, invisible to the public, is equally important part: The technology and infrastructure with which these new LTE transmission facilities are operated and controlled, the so-called core network, changes radically. This core network for LTE (Engineered packet-based core network) and Evolved Packet Core Evolved Packet or designated system. It basically works like the normal Internet, the technical term for this technology is an IP-based network or English an all-IP network. But what does that mean and how this network is different from a GSM network or a UMTS network, so what is the new in it?

GSM, UMTS and LTE networks: the differences

Put simply, the current mobile phone networks were completely fixed, or in large part on voice telephony. The GSM network, the second generation of mobile phone was originally designed as a pure network; other functions such as SMS and data transmission were then gradually it. The UMTS network calls and sending large amounts of data as equal functions together. The core network is divided into a part of UMTS, which provided fixed channels for the transmission of telephone calls (circuit switched) and one of the different data sets – like the Internet – transported.

The LTE network has – like the Internet – the absolute data priority. Telephoning is thus only one of many sub-functions of data transmission. A development is reconstructed, which is advanced in the fixed network have further calls is no longer handled through a separate channel, but runs as a Voice over IP over the Internet.

Which then affects the manner in which the LTE core network works: It is anything from one terminal to the other terminal to the Internet technology – are transmitted – the Internet Protocol, or IP. Technically speaking, it is an IP-based network or an all-IP network.

This fundamental change in the net makes the data transmission speed – both for downloading and sending, as well as in the reaction times. The Australian IT specialist Stuart Corner says: It is not primarily be the new LTE data radio technology, which allows high speed jumps, but most of all the new core network.

Signaling data: By registering for the bill

The new network is allocated differently: Over a part of running the so-called signaling data – for example, the registration of the participant in the network, its verification and identification, the location of their mobile device – the other part of the so-called user data – ie services that he accepts the scheme as phone or mobile Internet.

Among the parts that manage the signaling data and edit include Management Mobility Entity, short MME (Management of the mobile units), the Home Subscriber Server, short HSS (Subscriber Server) and the Policy and Charging Rules Function, briefly PCRF (fees office).

Logs in the MME to the mobile device, and then is forwarded to a location which the services – manages – ie the data transmissions. The MME also retrieves the information about the customer at HSS – because they are deposited there, in the GSM and UMTS networks had this customer database the name of Home Location Register (HLR). The PCRF can – depending on the rate – to specific data flows from that terminal or declines; it calculates how much the service costs at the rate reserved by the customer and shall issue an invoice.

User data: designing services funneled through the net

The services themselves are carried out in the so-called SAE gateway. The acronym stands for System Architecture Evolution Gateway – and said in German as the main interface for the network. This gateway consists of two areas: First, since the serving gateway is – short SGW in German about services portal. There the user’s terminal is managed by the application at the MME continues. It remains registered so when the user switches between two cell towers or when switching from LTE to a different wireless technology. It takes the data packets received by the user sends – for example by surfing – and forwards it to the exit.

The output is referred to as PDN Gateway, which is German for Public Data Network Gateway as portal to the public networks. And that is its function: Here the data to other networks – other mobile networks, Internet – forwarded and received the input data for the terminal of customers and forwarded.


LTE Speed

The new mobile technology Long Term Evolution (LTE ) promises particularly high rates of data transmission: Both when downloading from the internet, and when sending data, the speed is much faster than the older LTE wireless data technology UMTS with HSPA.

LTE Receiving data

In LTE networks, which are currently being commonly built in Asia and Europe, the operation speeds of theoretically up to 50 megabits per second (Mbit/s) when receiving data are already available. HSPA+, fastest wireless technology in 3G mobile network enables downloading of theoretically up to 43.2 Mbit/s.

LTE may actually even more. However, at speeds up to one gigabit per second (Gb/s) are possible only under laboratory conditions. The data rate depends on several factors. Determined the width of a frequency channel, the amount of data can be sent simultaneously. Several antennas increase in the transmitter and the receiver velocity.

What is the real average speeds will be using LTE in reality remains to be seen. In the U.S. you get in well-developed LTE network of Verizon Wireless at an average speed of about 10 megabits per second and can compete with DSL connections.

The transmission of data

When sending data rates, download can also be achieved, far higher mathematically than the current transmission rate. Technically feasible there are theoretical data rates of up to 86.4 Mbit/s.

Once again, we will have to see how high the rate offered is real then. It is determined by the technology, but also through the utilization of the radio cell or the distance of the user to the transmission tower.


LTE Standardization

3GPP is initiative responsible for the standardization of LTE mobile technology. 3GPP Stands for Third Generation Partnership project.


The initiative focuses on the standardization of LTE and third generation wireless technologies such as UMTS.


Technical specifications of LTE


In various releases since 1999, the 3GPP initiative has published technical specifications for different areas of mobile communications technology. The release 8 focuses on the standardization of LTE technology and is the most recently completed. In releases 9 AND 10 further standardization of LTE technology are made.


Release 9 is concerned with improvements and enhancements of HSPA and LTE Release 10 defines the technical specifications of LTE-Advanced. For Release 9, the development of the remaining issues to be completed in March 2011. Release 10 is still under development, a completion data is unknown.


About 3GPP


3GPP was created in 1988 with the goal of creating a global mobile applicable third generation system. Practically to the standardization by 3GPP to enable the users to get in as many networks worldwide with the same equipment, the same services as in his home network. The detailed technical specifications are intended to describe all aspects of mobile technology so precise that the mobile devices of all manufacturers without errors on all cellular functions.


The initiative consists of 3GPP Organizational Partners (OPs) and Market Representation Partner (MRP). OP’s are the world’s defining standards bodies in the IT industry: the Association of Radio Industries and Business, Japan (ARIB), the European Telecommunications Standards Institute (ETSI), the Alliance for Telecommunications Industry Solutions, USA (ATIS), the Telecommunications Technology Associations Korea (TTA), the Telecommunications Technology Committee, Japan (TTC) and the China Communications Standards Association (CCSA). About this Organizational Partners worldwide a majority of all mobile operators, manufacturers and regulators is organized in the 3GPP initiative.

LTE – Investments, Costs and Profits

Mobile operators have pulled out of the expensive purchase of UMTS licenses, the expensive construction of UMTS networks and the subsequent price of their teachings battle for customers.


But with LTE, users pay only a fraction of the transmission frequencies. For network construction, the price is the decisive criterion in selecting among the network equipment. And customers for data services in LTE networks will have to pay significantly more than what they have been accustomed to from UMTS networks.



UMTS: The more data, the more cheaper


The mobile plan has a problem; you need to inject more data into ever cheaper prices through their wireless networks. Since the new technology LTE is just right, the cost of production for fast data transmission in mobile communications should be lower. The cost per bit is lower for the network operators from four to ten times more than in HSDPA. This is also related to the fact that through new applied in LTE radio technologies, such as multiple-antenna method MIMO or the new modulation schemes OFDMA, with ten times more. LTE phones can be provided at a location with high speed internet than with UMTS. With LTE, so the profit margin is the mobile data tends to increase and the number of potential customers multiplied at one location.



LTE Expansion Cheaper than UMTS


The cost of the LTE expansion circulates different numbers. The bidding for the frequencies is already certain.


Expenditure incurred in the bidding for the frequencies, the cost for network deployment. The US firm Aircom, a network specialist, estimates that a mobile operator in Central Europe needs to spend about 670 million euros for the LTE network construction in the first year.


Lot of costs should come together after all, it must not only upgraded base stations to LTE or LTE base stations will be built, it must be a new IP-based core network to be created. And finally, the data lines must be upgraded from the base stations to the new core network to process the large amounts of data, because what good is fast wireless network if it only blcks the access to the core network. This looks like a high investment.


Pressure on network equipment


In order to make sense economically, the LTE expansion should cost only a fraction of what was spent on the construction of UMTS network, so the experts explain the Finnnish IT consultancy Rewheel. My solution to this dilemma: The network equipment should rethink their pricing somewhat.


New tariffs: LTE’s are not as bargain


After the business model was not a UMTS rousing success for many years, the mobile operators want LTE would not have to wait due to the investment pays.


And that probably means that they do not just invest less than in the UMTS networks, but they will charge higher prices at the retail level.


LTE is surely not only once at a bargain price.

A Brief History of LTE

The short history of LTE shows only five years it took from the start until the introduction. This follows the mobile a trend that can be observed in new technologies: What is now on the market, may have a million customers in near future.


Digital Mobile Radio: from GSM to LTE


The first phone last 28 years to crack 10 million mark of users. The cable television made it in 25 years to get the phone in 9 years, the wireless data transmission in 6 years, from zero to ten million customers. Faster new technologies are accepted by the mass market.


The new LTE technologies were developed as fast as any other telecommunications technology. For comparison: In 1982, the development of GSM by “Groupie Special Mobile”. It was launched by the European Conference of Postal and Telecommunications Administrations. In 1991, the first GSM network in Finland went on the air. In 1992, GSM set internationally by the market. In 1987, the UMTS Basic Research, 1992, the frequencies stipulated for 2001 launched the first commercial UMTS network, followed by the Standards for the additional technology to quickly send HSDPA(2002) and HSUPA (2005).


The UMTS technology was initially developed hesitant, we had already a digital mobile radio standard and the number of applications for faster wireless data transfer was still very manageable. Later, the networks were constructed reluctant, partly because they had to pay high license fees and the lack of money for investment, partly because the applications bring quick profits, were not in sight.


In LTE, it goes very fast


LTE everything goes much faster. For those applications that need more and more data faster by radio are finally been on UMTS market.


LTE is considered the birth of 2004, when in Toronto, held a workshop on wireless networks and LTE. About forty mobile operators were represented, to research institutes and universities. As a result, created a study on how to rapidly develop and build a fast data network, has short response times and nearly bring the performance of a wired network.


In June 2007, the standard for new mobile technology is being committed. In 2008, Ericsson unveils the Mobile World Congress in Barcelona, the first time establishes a connection between two compact LTE terminals, there will be a transfer rate of 25 mbps per second achieved.  End of 2008, the Korean company LG to introduce the first-install LTE chip, it could reach peak speed at 60Mbps.


Finally, in December 2009, the first commercial LTE network in Sweden is put into operation, in late summer and fall of 2010 in Germany, the first LTE phone masts ready.

LTE: The Fastest Developed Technology


For the Global Supplier Association, a global trade association for the mobile industry, LTE is now “ the most rapidly developing technology in the history of telecommunications.”


Meanwhile, large-scale commercial LTE networks available in many countries and areas.

LTE Surf Sticks

LTE Sticks are technically radio modems, meaning little combined transmitting and receiving equipment, which operate on different frequencies.


They can be connected via the USB ports to virtually any device such as a larger netbook, laptop or home PC. The sticks are in demand, such as to use abroad, or a change to a new and faster wireless data technology, and they are easy to replace. In addition to the relatively small size and low weight, this versatility and the slight changes are the greatest advantage of the sticks.


Even with the older data radio technologies of UMTS and GSM, sticks still dominates the modem market, other solutions such as built-in modem or modem card format to be used much less frequently. For the majority of users, LTE Surfsticks will be the solution that makes mobile internet the fastest and easiest access.


The new LTE Sticks come from the Far East, currently dominate the South Korean manufacturer Samsung, LG Electronics and Pantech market, China’s Huawei tries to win over new entrants.


So the first LTE Stick was Samsung GT-B3740, which is developed by Samsung in Vodafone Brand. The next stick from Swedish-finished network operator Telia Sonera is the GT-B3710 from Samsung. Meanwhile, there is B3730, which dominated alongside LTE is UMTS and HSPA, GSM and EDGE, as well as wireless technologies. The device sends in LTE mode on the frequency 2600MHz. It is also used in the Vienna LTE network of the Austrian mobile operator A1 Telecom Austria. The B3740 is likely to be an optimized version with a similar standard.


The second LTE stick comes from Chinese mobile phone supplier, HUAWEI, it is HUAWEI E398. The device was tested in the LTE network of O2 and is now available at Telekom from the second half of 2011. In Austria, it is the mobile operator A1 Telekom Austria offered on its website.



Global Supply of LTE Sticks


There are very few data sticks, which are with wireless data LTE technology, so pure LTE Sticks have others technologies backward, such as UMTS, GSM and CDMA 2000 network to send and receive. Overall, a clear trend is emerging to stick with multi-technology, pure LTE Data sticks are shunned by the mobile operators.



The Pantech UML290, originates from South Korea, and sells for US Verizon Wireless LTE network. It’s like the stick used in Scandinavia and Austria from Samsung, sends an older and slower wireless technology on board. In the case it is spread in the U.S. CDMA 2000, and therefore he receives on 800 Mhz and 900 Mhz. For LTE reception, it is in the range of 700 MHz road.


The second stick, Verizon Wireless LG VL600 of the South Korean manufacturer LG Electronics. With LTE, it’s in the 700 MHz band travelling with the frequency used the U.S. 3G CDMA 2000 technology, it can send and receive on the 800MHz and 1900MHz band. LG Electronics also has the LD 100 model that is used in Japanese LTE network of Docomo. It also speaks several wireless data technologies, besides LTE, there is UMTS and HSPA, plug for the Japanese to travel abroad, GSM and GPRS are also included. GSM will be gradually switched off in Japanese networks.


What to look for LTE Sticks


All LTE Sticks on the market are significantly larger than the surf sticks with pure UMTS or GSM technologies; they therefore require more space on your laptop. If two or more USB ports close together, this may lead to another USB ports blocked. Therefore a rotatable mechanism for raising the stick is very useful to save some space with a bent 90 degrees stick, and most of these sticks have rotate mechanism.


Pure LTE Sticks can only be used where LTE is available. Since the LTE network is expanding coverage in many areas, it would take many years for LTE network to cover every corner. Therefore in some areas, you have to use other technologies UMTS and GSM, and the associated wireless data technologies HSPA and EDGE, to dominate the modem.


Several sticks offer external antenna connectors; one is for the older mobile technologies and one for LTE. This is an important consideration when buying, LTE will be predominantly at home or hospital use, we recommend you might install an LTE external antenna.

LTE Smartphones

The first LTE Smartphone brough the Korean company Samsung with model “Craft” on the market, it is from the regional provider MetroPCS LTE in its LTE network in Las Vegas and currently offered in many other urban regions.


The Craft dominated the radion data technology LTE and common in the US technology of the third generation mobile CDMA 2000. The latter is also urgently needed, as is still the problem of voice transmission through LTE unresolved. Must the “Craft”, when a phone call is made, switch to the CDMA network. Then abort the current download and it can simultaneously send and receive in two technologies and the unit now not even. In short: if you surf and there is a phone call, you can fly from the Internet.


According to the manufacturers and mobile operators 2011 is the year of LTE smartphones. This applies first of all to the market in the U.S. Here is the LTE rollout in the area so far advanced that there are enough customers for such devices.


Besides the already mentioned Craft by Samsung, there are no Metro PCS, a second LTE smartphone of the Korean Samsung “Galaxy Indulge”.


The “Thunderbolt”, were announced as the new LTE Smartphone by the Taiwanese company HTC, and the US. Mobile phone manufacture Motorola model “Bionic” and the Korean LG model “Revolution”.


Tips for LTE Smartphones


And LTE Smartphone should be proficient in addition to the latest and fastest data transfer technology, the transmission in UMTS networks including HSPA(and possibly HSPA+) with GPRS and EDGE and GSM networks in the second generation mobile. It must be as quickly as possible. Finally, it will take years for the LTE networks everywhere. And many customers want apart from the major urban centers to the mobile internet.


When purchasing a LTE Smartphone, an important point is to know the telephone solution. This equipment is recommended to perform without net change, when you call out. However, currently, it’s not yet clear when devices will have this capability on the market.

SMS in LTE—Only use the time-proven Technology

With new LTE Smartphones, which are available in many markets now, users want to get exactly the same services as the old UMTS smartphones, the service includes SMS.


The SMS is, in evolutionary, actually a waste product. In GSM and UMTS networks, there is so-called signaling channel, which is used for user to display the signal strength of its cellular network. There was in the early days of mobile phones still free space and so they came up with the idea of sending short text messages via this radio channel. The success surprised the inventor. Developed to today, some phones seems to become the second function of a mobile phone, and this function should continue under LTE netwoks.


SMS is also continued on the old networks


At the point under the LTE network, which is responsible for signaling data, SMS is then processed over GSM or UMTS networks forwarded. Thus, even a lot of SMS services continue to be used, which have proven themselves – such as the configuration of mobile phones via SMS – without having to make major changes. The technical term for this SMS technology in LTE networks “ Circuit Switched Fallback for SMS”.


The Future: SMS as a simple Internet File


The alternative is to completely treat the SMS in LTE network. This will eventually be made. But for this you have to build an entirely new element in LTE networks – the so-called IP multimedia Subsystem. This element is everything – to put it simply – as an Internet file treats – from voice call up just to SMS.


This is complex, as the example shows SMS:  If you want to existing services – such as smartphone SMS configuration – switch to the new mode of transmission, you need to build these services virtually from scratch – with the provider as the terminal of the customer. This costs time and money.