Examples

Ex	Messages on Originating Call Leg	Ingress SIP Interface Config	Ingress SIP Interface Config	Messages on Terminating Call Leg
1	INVITE → Supported: timer SE: 200 ← 200 OK Require: timer SE: 200; refresher=uas INVITE → Supported: timer SE: 1200; refresher=uas ← 200 OK Require: timer SE: 500; refresher=uas	session-expires: 500 min-se: 200 request-refresher: none response-refresher: uas this element becomes refresher	session-expires: 500 min-se: 400 request-refresher: none response-refresher: uas	INVITE→ Supported: timer SE: 500 Min-se: 400 ← 200 OK Require: timer SE: 400; refresher=uas
2		session-expires: 500 min-se: 200 request-refresher: none response-refresher: uac this element becomes refresher	session-expires: 500 min-se: 400 request-refresher: uas response-refresher: uas this element becomes refresher	INVITE → Supported: timer SE: 500; refresher=uas Min-se: 400 ────────────────── ← 200 OK
3	INVITE → Supported: timer SE: 1200; refresher=uac Min-se: 800 ────────────────── ← 200 OK Require: timer SE: 800; refresher=uac	session-expires: 500 min-se: 200 request-refresher: none response-refresher: uas	No session timer configuration this element becomes refresher	INVITE → Supported: timer ────────────────── ← 200 OK Require: timer SE: 400; refresher=uac
4	INVITE → Supported: timer SE: 200; refresher=uac ────────────────── ← 200 OK Require: timer SE: 200; refresher=uac	session-expires: 500 min-se: 200 request-refresher: none response-refresher: uas	No session timer configuration	INVITE → Supported: timer ────────────────── ← 200 OK
5	INVITE → Supported: timer SE: 200 ────────────────── ← 200 OK	No session timer configuration	session-expires: 500 min-se: 400 request-refresher: uas response-refresher: uas this element becomes refresher	INVITE → Supported: timer SE: 500; refresher=uas Min-se: 400 ────────────────── ← 200 OK
6	INVITE → Supported: timer SE: 200 ────────────────── ← 200 OK Require: timer SE: 400; refresher=uas	No session timer configuration SBC behavior stays same as current behavior	No session timer configuration	INVITE → Supported: timer SE: 200 ────────────────── ← 200 OK Require: timer SE: 400; refresher=uas
7	INVITE → Require: timer SE: 200 ────────────────── ← 420 Unsupported: timer	No SIP feature for timer No session timer configuration SD behavior stays same as current behavior	No session timer configuration
8	INVITE → Require: timer SE: 200 ────────────────── ← 420 Unsupported: timer	SIP feature configured for timer No session timer configuration SD behavior stays same as current behavior	No session timer configuration	INVITE → Required: timer SE: 200 ────────────────── ← 420 Unsupported: timer
9	INVITE → Require: timer SE: 200 ────────────────── ← 200 OK	SIP feature configured for timer No session timer configuration	session-expires: 500 min-se: 400 request-refresher: none response-refresher: uas this element becomes refresher	INVITE → Supported: timer SE: 500 Min-se: 400 ────────────────── ← 200 OK Require: timer SE: 500; refresher=uac
10	INVITE → Require: timer SE: 200 ────────────────── ← 200 OK Require: timer SE: 200; refresher=uac	No SIP feature for timer session-expires: 500 min-se: 200 request-refresher: none response-refresher: uac	session-expires: 500 min-se: 400 request-refresher: uas response-refresher: uas	INVITE → Supported: timer SE: 500; refresher=uas Min-se: 400 ────────────────── ← 200 OK Require: timer SE: 500; refresher=uas
11	INVITE → Require: timer SE: 200 ────────────────── ← 420 Unsupported: timer	No SIP feature for timer No session timer configuration	session-expires: 500 min-se: 400 request-refresher: none response-refresher: uas
12	INVITE → SE: 200 ────────────────── ← 200 OK SE: 500; refresher=uas	session-expires: 500 min-se: 500 request-refresher: none response-refresher: uas this element becomes refresher	No session timer configuration	INVITE → ────────────────── ← 200 OK
13	INVITE → ────────────────── ← 200 OK	No session timer configuration	session-expires: 500 min-se: 400 request-refresher: none response-refresher: uas	INVITE → Supported: timer SE: 500 Min-se: 400 ────────────────── ← 200 OK Require: timer SE: 400; refresher=uas
14	INVITE → ────────────────── ← 421 Require: timer	No session timer configuration SD behavior stays same as current behavior	No session timer configuration
15	INVITE → Supported: timer SE: 200 ────────────────── ← 422 Min-se: 400	session-expires: 500 min-se: 400
16	INVITE → Supported: timer SE: 200 ────────────────── ← 200 OK Require: timer SE: 200; refresher=uac	session-expires: 800 min-se: 90 request-refresher: none response-refresher: uac	session-expires: 800 min-se: 90 request-refresher: none response-refresher: uac	INVITE → Supported: timer SE: 800 Min-se: 90 ────────────────── ← 422 Min-se: 900 ────────────────── INVITE → Supported: timer SE: 900 Min-se: 900 ────────────────── ← 200 OK Require: timer SE: 900; refresher=uas