- This topic has 3 replies, 1 voice, and was last updated 16 years, 2 months ago by Dennis.
17th March 2005 at 11:24 #40752DennisGuest
Do you have practical experience with GSM technology that BSS allocates the A interface (BSC-MSC) circuits? In all networks I have seen there always allocaction is done by MSC and selected CIC is present in ASSIGNMENT REQUEST message. But in spec is described also allocation of A CIC by BSC (MSC gets info about selected CIC in ASSIGNMENT COMPLETE msg.) Have you ever seen this?
With this is connected also strange procedure started by CHANGE CIRCUIT from the MSC to the BSS. It requests a change of the circuit allocated to a connection. BSC replies by CHANGE CIRCUIT ACKNOWLED where is present new A CIC selected for call – have you ever seen this procedure in practice. Do you have idea if it is supported by some vendor?17th March 2005 at 21:12 #40753OliverGuest
I do not know if this is a standard requirement but it is supported by Nokia BSC.
In this case you have to defined an erase hunting group so BSC allocates circuits on A interface.
This gives you a faster call setup and save signalling over A interface.
BR18th March 2005 at 02:52 #40754Mohsin IsmailGuest
Hi Oliver and dennis
It’s very interesting features and very useful for network dimensioning and design between MSC-BSC. Oliver did you have any signalling trace for this features? Is very appreciate if you can email to me..
And dennis, could you please specify the spec referrences so as I can read further.
Mohsin18th March 2005 at 08:50 #40755DennisGuest
to Mohsin – BSSMAP GSM 08.08
If I understood coretly – you wrote that Nokia BSC supports allocation of A CIC. I such case A CIC does not have to be allocated by MSC and can be allocated by BSC. It is not clear to me why it implies faster call setup???
It is not clear to me “an erase hunting group” – what does it mean.
Have you ever seen A CIC allocation by BSC in practice?
And what about change circuit procedure? I can imagine practical ussage eg. when A CICs are allocated by BSC and from MSC side you want to block some PCM E1 on which some active call are running. Prior blocking you can reallocate CIC to other E1 PCM by change circuit procedure… Do you have any other idea for what this procedure can be useful? Have you ever seen it in practice?