Welltech SIPPBX 6200 V.3.1.0 User Manual
Page 42
Welltech Computer Co., Ltd.
SIPPBX 6200S/GS Release 3.1.0 User Guide
- 42 -
Figure 4.1-2
Advance Parameter Description:
• Call Validation Time: The timer to check periodically call is valid or not.
SIPPBX 6200 will send re-INVITE periodically for call validation. This
parameter also refers to the session timer RFC 4028 Min-se header. 422
will be sent when Session-Expires is smaller call validation time.
• NAT Compare Method: How to detect a NAT user
- IP Only: Compare IP only
- IP / Port: Compare IP and UDP port
• RetransmissionT1 (msec.): T1 determines several timers as defined in
RFC3261. For example, when an unreliable transport protocol is used, a
Client Invite transaction retransmits requests at an interval that start at T1
seconds and doubles after every retransmission. A Client General
transaction retransmits requests at an interval that starts at T1 and doubles
until it reaches T2. (Default Value: 500ms) **
• RetransmissionT2 (msec.): Determines the maximum retransmission
interval as defined in RFC3261. For example, when an unreliable transport