Cisco Cisco Packet Data Gateway (PDG)
System Settings
▀ Configuring a Demux Card
▄ ASR 5500 System Administration Guide, StarOS Release 16
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Configuring a Demux Card
You can dedicate a DPC/UDPC or MIO/UMIO to function as a demux card. Demux is a generic term for signal
demultiplexing tasks. These are the tasks are responsible for parsing call setup (signaling packets) and distributing the
calls internally. For this reason there almost as many tasks running on a demux card as there are services.
demultiplexing tasks. These are the tasks are responsible for parsing call setup (signaling packets) and distributing the
calls internally. For this reason there almost as many tasks running on a demux card as there are services.
The vpnmgr tasks responsible for each context also run on the demux card. The number of vpnmgr tasks correspond to
the number of contexts. A vpnmgr is responsible for IP address assignment to mobile equipment, IP routing (such as
BGP, OSPF), as well as a variety of associated tasks.
the number of contexts. A vpnmgr is responsible for IP address assignment to mobile equipment, IP routing (such as
BGP, OSPF), as well as a variety of associated tasks.
Overview
Designating a DPC/UDPC or MIO/UMIO as a demux card frees up resources for session handling, which has the
potential to increase system throughput. However, there is no increased support in total subscriber capacity due to other
system resource restrictions.
potential to increase system throughput. However, there is no increased support in total subscriber capacity due to other
system resource restrictions.
This feature is disabled by default and can be enabled via the Global Configuration mode require demux command. It
is only supported for a limited number of products. Refer to the product Administration Guide for additional
information.
is only supported for a limited number of products. Refer to the product Administration Guide for additional
information.
Release 15.0 only supports designating the MIO/UMIO as a demux card for GGSN, P-GW, S-GW, HA and SAEGW
running on an ASR 5500. It is explicitly not supported for Ex-GW, MME and SGSN because these products use a
higher proportion of MIO/UMIO CPU resources.
running on an ASR 5500. It is explicitly not supported for Ex-GW, MME and SGSN because these products use a
higher proportion of MIO/UMIO CPU resources.
To support this feature session recovery must also be enabled via the Global Configuration mode require session
recovery command.
recovery command.
Important:
After enabling demux card and session recovery, you must save the configuration and reboot the
ASR 5500 to enable this feature.
Caution:
Enabling the Demux on MIO/UMIO feature changes resource allocations within the system. This
directly impacts an upgrade or downgrade between StarOS versions in ICSR configurations. Contact Cisco TAC for
procedural assistance prior to upgrading or downgrading your ICSR deployment.
procedural assistance prior to upgrading or downgrading your ICSR deployment.
MIO/UMIO Demux Restrictions
The following restrictions apply when configuring an MIO/UMIO with Demux functionality:
The require demux management-card command must be enabled before any service or context has been
created on the system. This command will not be allowed to execute once the ASR 5500 has picked a mode of
operation.
operation.
Once the chassis has booted with this feature enabled, non-supported services cannot be configured.
Up to 16 services are supported on an MIO/UMIO with demux functionality enabled. Certain services also
configure associated-services (sub-services) that count towards the maximum services supported.
Products that support a large number of VPN Managers, VRFs and/or a large number of Demux managers must
not use this feature. Up to 10 contexts, 250 VRFs and 64 interfaces per context will be supported with this
feature enabled. These configuration restrictions will be handled at configuration time.
feature enabled. These configuration restrictions will be handled at configuration time.