this is architecture of 3G technology now first question arises that what is 3G technical name ? some people say that 3G is wcdma this is wrong as a telecom Engineer you must know technical name for 3G technology so its technical name is UMTS(universal mobile telecommunication system) in wcdma there is an air interface so technically wcdma is not 3G you should never say 3G is wcdma this is 3G umts.
3g umts network
now we will see what is the major changes in 3G umts network for this you should know that whole network is divided into two parts one is UTRAN and second is CORE network as shown in above architecture you should remember that in 3G umts whatever changes made is in RAN part only there is no major changes in core network and no any hardware added in core network only hardware and software is upgraded in core network in 3G umts technology only hardware changes in RAN parts if you have study previous post 2G gsm architecture we say our mobile MS means mobile station but here in 3G umts architecture our mobile is called UE(user equipment) here in 3G umts architecture our mobile handset connect with NodeB if you remember in 2G gsm architecture our mobile was connected with BTS but here with NodeB so if in any architecture talk about NodeB then you must understand this is 3G umts architecture without any confusion NodeB will similarly work as BTS but this is new hardware upgraded in 3G umts architecture next NodeB is connected with RNC while in 2G gsm architecture BTS was connected with BSC so here RNC(radio network controller) will work like BSC manages and control radio resources one RNC will control many NodeB depends upon capacity of RNC but this is new hardware upgraded in 3G umts architecture hence this two major changes NodeB and RNC in hardware 3G umts architecture.
is umts 3g ?
now RNC is further connected with MSC with interface Iu-cs which is circuit switching for voice call and other RNC interface with SGSN(serving GPRS support node) Iu-ps interface which is packet switching used for data connection you can compare with 2G there was no internet service but in 3G umts we will get internet services with the help of new hardware SGSN so if you see the above 3G umts architecture RNC connect with two ways one for voice call use and other for internet service data connection and both the route is different hence in 3G umts internet service is available due to new hardware addition when you made voice call then your request goes through mobile to NodeB and NodeB to RNC and RNC to MSC and GMSC like this but when you want to connect to facebook server then your request similar goes to RNC now from RNC to SGSN and SGSN to GGSN(gateway GPRS support node) and will connect to facebook server and you will use the internet service CG is charging gateway which is use for data used by user you get the message alert you have used 10Mb data and your balance data is 100Mb this is done by charging gateway.
BG is boarder gateway which is used for connection of network in other circle when you go to roaming.
MSC server is use for all authentication purpose but MGW (media gateway) allocate the channel for call setup here MSC is divided into two parts MGW and MSC server user plan and control plan.
other hardware like GMSC, HLR,AUC,EIR we have already discussed in details in 2G gsm architecture you can refer now we will discuss here working of SGSN.
SGSN(Serving GPRS support node) function
SGSN routing and transfer data,mobility management, logical connection link control,help in billing, authentication, location update,current VLR now SGSN verify your authentication then request is forwarded to GGSN.
GGSN(gateway GPRS support node)
it is like a router connect your mobile to internet which server you want to access, current SGSN address save more than one SGSN GGSN connect and save its current address.
One RNC can communicate with other RNC with the help of Iur interface in 3G umts architecture but in 2G gsm architecture one BSC can not communicate with other BSC this is important feature of RNC.
now very important point whenever there is change in RAN part then your handset mobile or user equipment will change so from 2G to 3G umts hardware changes in RAN part so your mobile is change to 3G here 2G gsm mobile will not support you have to purchase 3G mobile.
next important point in 2G technology mobile is called MS means mobile station but in 3G umts architecture mobile is called UE(user equipment) because 3G mobile working as laptop all feature enable like internet,touch screen,camera,whats up every feature is available like equipment so it is called user equipment. 3G umts bandwidth available is 5MHz but the actual channel bandwidth we get in 3G umts is 3.84mbps the frequency available in india for 3G umts is 2100MHz 0r 1800MHz.
now we will continue in next post keep reading i hope you have enjoyed learning 3g umts thanks for reading and sharing to others.
dated 2nd Oct 2018.