Cisco ASR 5500 System Administration Manual page 354

Session Subsystem
Task Description
ipsgmgr IP Services Gateway Manager
l2tpdemux L2TP Demultiplexor Task
l2tpmgr Layer 2 Tunneling Protocol
Manager
linkmgr SS7 Link Manager
ASR 5500 System Administration Guide, StarOS Release 21.5
328
Function
Created by the Session Controller.
In Server mode, acts as a RADIUS server, and supports Proxy functionality.
In Snoop mode supports snooping RADIUS Accounting messages.
Load balances requests among different SessMgrs.
Activates and deactivates sessions.
Created by the Session Controller when an LNS service is created. Only
one L2TPDemux task is invoked for the entire system.
De-multiplexes and forwards new incoming tunnel create requests to
L2TPMgrs.
Maintains information about current active tunnels in all L2TPMgrs.
Load balances requests among L2TPMgrs.
With session recovery (SR) enabled, this demux manager is usually
established on one of the CPUs on the first active packet processing card.
Created by the Session Controller for each context in which a LAC or
LNS service is configured. Additional managers are created as needed
depending on loading.
Responsible for all aspects of L2TP processing.
Maintains protocol state machines for all L2TP sessions and tunnels.
Triggers IPSec encryption for new L2TP tunnels as needed.
Works with Session Managers to gracefully bring down tunnels.
With session recovery (SR) enabled, this demux manager is usually
established on one of the CPUs on the first active packet processing card.
Created by the Session Controller when the first SS7RD (routing domain)
is activated.
Multi-instanced for redundancy and scaling purposes.
Provides SS7 and Gb connectivity to the platform.
Routes per subscriber signalling across the SS7 (including Iu) and Gb
interfaces to the SessMgr.
StarOS Tasks