AltiGen MAXCS 7.0 Update 1 ACM Administration - Manual (Page 147)

Configuring Virtual Board HMCP
MaxCS 7.5 Administration Manual 131
• When adding additional combo licenses, the system will also increase the RTP ports it uses and will use
these new ports. If these additional ports are not added to the firewall ,calls will not have audio.
• 1,000 G.711 voice processing resources will be licensed to the system when one HMCP Media Server
license is registered.
• The more VPR assigned, the slower the system will be when it starts up. To calculate the optimized
number of VPR you need, use the following formula:
Total G.711 VPR = Total number of extensions X 2
Total G.711/G.722/G.723/729 VPR = Total number of remote IP phone users + Total Tie Trunk Channels
that will use compressed codec
• Adding HMCP licenses or changing assigned numbers does not require restarting the AltiGen switching
service.
• In the event that you need to decrease the assigned numbers of HMCP resources (reassigned to the
second HMCP server, for example), the system must be rebooted for the configuration to take effect.
Parameters in IP Header —QoS and TTL assignments.
QoS assignment – IP TOS/DiffServ Byte Value. The default TOS/DiffServ byte hex value "A0"
(10100000) signals the network switch and router that RTP packets are "Critical". To set the value for
Diffserv Code Expedited Forwarding (DSCP EF), you can enter hex value "B8" (10111000).
TTL assignment – For IP paging multicasting only. The purpose of the TTL (Time To Live) is to regulate
how many hosts the IP paging packets can pass through. The TTL value is reduced by one on every hop.
You may need to adjust this value if there are remote AltiGen IP phones at different locations that register
to MAXCS through WAN and require the IP paging feature. The value will be the number of routers from
MAXCS to remote IP phone plus one.
Media Pass-Through Support for HMCP
Another MaxCS 7.5 enhancement for system performance and voice quality is the Media Pass-through
feature. This feature applies only to HMCP Softswitch systems; it is enabled by default.
While the Media Pass-through feature is enabled, the HMCP driver doesn’t need to do encoding and decoding
on both channels. This approach has the following benefits:
• Improved system performance, because no MIPS is required for codec processing
• Improved voice quality, because no distortion is introduced by additional compressed codecs
• Reduced voice latency, because it eliminates the delay introduced by codec and jitter buffer processing
In addition to benefits to direct calls, pass-through applies during call recording, silent monitoring, and
coaching.
G.722 pass-through is enabled by default.
Conditions Not Supported
Media pass-through cannot support all conditions in the HMCP system, even if both connected channels are
using same codec. The following MAXCS features do not supported media pass-through:
• Call playing – The trunk call playing must use encoder and decoder on RTP channel
• Conference calls – All RTP channels in a conference bridge must be encoded and decoded voice
Assign HMCP Resources to IP Extensions
After you configure the HMCP board, you need to configure extensions to use the HMCP voice processing,
conferencing, and recording resources.