ISUP call flow between switches and the end entity

[savita.sharma]

hello,

I m havin' some confusions with the flow of signalling packets between switch nodes.

as we see in cisco and few other documents they say that :

phone ---------- --switch------------ss7------------switch-------------------------phone2

call start--------- >switch--IAM1--->ss7---IAM2-->switch-----call setup-->phone2

ring tone <-----switch<--ACM1--SS7<---ACM2-switch<--alerting----------phone2

what i m want to know is .

Is it that ,moment IAM1 is sent to the 1st switch ACM1 is sent back and then IAM2 is sent to the next swith which pages the called party if not busy , sends ACM2 .???

Pls confirm this .

savita

[Chester Rieman]

Savita,

Here is how it should work:

Originating Intermediate terminating

office office office

|------------IAM------------------>| |

| |--------------IAM2--------->|

| |<-------------ACM-----------|-

|<----------ACM2-----------------| |-

Hope this helps

[savita.sharma]

what happens in a cascading situation? does the flow remails same ?

Savita