Akuvox SP-R5xP, Руководство администратора

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Administrator’s Guide for Akuvox SP-R5xP IP Phones
Akuvox Proprietary and Confidential. Copyright © 2014 Akuvox network Co., Ltd..
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Parameter Description
Priority Specify preferential treatment for the specific host entry. Lower
priority is more preferred.
Weight When priorities are equal, weight is used to differentiate the
preference. The preference is from highest to lowest. Keep the
same to load balance.
Port Identify the port number to be used.
Target Identify the actual host for an A query.
SRV query returns two records. The two SRV records point to different hosts and have the
same priority 0. The weight of the second record is higher than the first one, so the second
record will be picked first. The two records also contain a port “5060”, the IP phone uses this
port. If the Target is not a numeric IP address, the IP phone performs an A query. So in this case,
the IP phone uses“server1.akuvox.pbx.com" and “server2.akuvox.pbx.com" for the A query.
Outgoing Call When the Working Server Connection Fails
When a user initiates a call, the phone will go through the following steps to connect the call:
1. Sends the INVITE request to the primary server.
2. If the primary server does not respond correctly to the INVITE, then tries to make the call
using the secondary server.
3. If the secondary server is also unavailable, the IP phone will try the fallback server until it
either succeeds in making a call or exhausts all servers at which point the call will fail.
At the start of a call, server availability is determined by SIP signaling failure. SIP signaling
failure depends on the SIP protocol being used as described below:

If TCP is used, then the signaling fails if the connection or the send fails.

If UDP is used, then the signaling fails if ICMP is detected or if the signal times out. If the
signaling has been attempted through all servers in the list and this is the last server, then
the signaling fails after the complete UDP timeout defined in RFC 3261.
If it is not the last server in the list, the maximum number of retries depends on the configured
retry count.
Procedure
Server redundancy can be configured using the configuration files or locally.
Configuration File <r0000000000xx>.conf/
<MAC>.conf
Configure the transport type on the IP phone.
For more information.