ARCH wait on SENDREQ wait event

 I see "ARCH wait on SENDREQ" as always the top event in my production database.

DB Ver: 9.2.0.8

OS: MS 2003 Server

Data Guard was implemented on similar type of system. Network team informed that network response is good between the primary and stand by systems.

Top event in statspack report:

Top 5 Timed Events
~~~~~~~~~~~~~~~~~~                                            % Total
Event                                               Waits    Time (s) Ela Time
-------------------------------------------- ------------ ----------- --------
ARCH wait on SENDREQ                  524         736       53.44

Please find the few parameter details on primary DB:

_log_archive_callout                 string      LOCAL_FIRST=TRUE

log_archive_dest_1                   string      LOCATION=F:\arch\<ISD>

log_archive_dest_2                   string      service= <TNS_SID> arch reopen=60