Iu-CS in UMTS

Hi,

I understand that Iu-CS is the interface in UMTS which links the RNC
(Radio Network Controller) with a 3G MSC (3G Mobile Switching Centre).

But, what is the expansion/meaning for 'Iu' in 'Iu-CS' ?
I searched the internet, but i did not find relevant info about it.
I find info that CS is for Circuit Switch. But not for 'Iu'.
Any ideas ?

Thx in advans,
Karthik Balaguru

Iu means interface in UMTS. There is no expansion for it.

In UMTS you have:
IuB - Interface between the Base Stations and the RNCs
IuCS (part of the Iu) - Interface between RNCs and the Core for
circuit switched services (voice, video telephony)
IuPS (part of Iu) - Interface between RNCs and the Core for packet
switched services (data)
IuR - Interfance amonst RNCs

Faisal...

On 26 Sep, 23:49, karthikbalaguru <karthikbalagur...@gmail.com> wrote:
> Hi,
>
> I understand that Iu-CS is the interface in UMTS which links the RNC
> (Radio Network Controller) with a 3G MSC (3G Mobile Switching Centre).
>
> But, what is the expansion/meaning for 'Iu' in 'Iu-CS' ?
> I searched the internet, but i did not find relevant info about it.
> I find info that CS is for Circuit Switch. But not for 'Iu'.
> Any ideas ?
>
> Thx in advans,
> Karthik Balaguru