Chapter8. SIP Services
Allowed number of concurrent sessions
Enterthe number of concurrent SIP sessions which the Telecommuting Module should handle.
Leavethe field empty to allow as many sessions as there are SIP traversal licenses on the Telecommuting Module
(numberdisplayed inside parantheses). You can purchase additional SIP traversal licenses from your retailer.
Requests
Youcan configure timeouts for the different functions of the Telecommuting Module SIP module here. It is not
recommendedto change from the default values unless you really know what you’re doing.
Default timeout for INVITE requests
Whensending an INVITE request you can specify a timeout, telling how long you can wait before getting an
answer.
Ifno timeout is given when an INVITE request is sent, the Telecommuting Module sends the default timeout
enteredhere.
Maximum timeout for INVITE requests
Here,enter the maximum timeout to allow for an INVITE request. If a higher timeout is given, the Telecommuting
Modulechanges it to the value entered here.
SIP blacklist interval
Whenthe Telecommuting Module sends out a SIP request and no reply is received, the SIP peer (say, a SIP server
oran IP phone) will be blacklisten for the given time interval. This blacklisting means that no new SIP requests will
besent to the unit, even if requests that should be routed to this unit is received by the Telecommuting Module.
Ifthe SIP request which caused the blacklisting, or a subsequent SIP request for that unit, can be routed to another
deviceinstead, the Telecommuting Module will keep on sending those requests to the next known IP address for the
domain/userin question. When the blacklist ends, the Telecommuting Module will go back to sending requests to
thepreviously blacklisted unit again.
Ifa 0 is entered into this field, the SIP blacklisting will not be used by the Telecommuting Module.
Base retransmission timeout for SIP requests
Whenthe Telecommuting Module sends out a SIP request, it will expect a reply within a certain time. If no reply
hasbeen received within the Base retransmission timeout, the Telecommuting Module will start resending the
request.
Maximum number of retransmissions for INVITE requests
Whenthe Telecommuting Module sends out an INVITE request, it will wait for a reply until the Base
retransmissiontimeout and then start to retransmit the request. The time intervals between retransmissions will
doublefor each new retransmission.
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