This feature is
license controlled. Contact your Cisco account representative for information
on how to obtain a license.
When the User
Equipment (UE) is unreachable due to 'Power Saving Mode' or 'Extended Idle Mode
DRX', there might be high latency for initial response before the exchange of
packets, which is the time taken by the UE to establish a connection and
initiate data transfer. Owing to high latency, there is a need to buffer data
for a longer duration.
Communication (HLCOM) feature introduces buffering of MT data at the S-GW (part
of SAEGW), when the UE is in a power saving state and not reachable.
buffering time duration or the packet count is based on the first successful
DDN Ack carrying those parameters. No new DDNs are initiated once the call is
received and HLCOM parameters start buffering the packets. Other features such
as "Priority Paging" do not override the HLCOM UE. Packets buffered are not
recovered and neither the state of the HLCOM. Buffered packets are lost on
recovery. HLCOM duration and packet count to be buffered is not recovered.
Hence, any packet post recovery triggers DDN.
configurations, and timers are independent of existing IDLE mode of buffering.
This means that the buffer allocated for HLCOM is more than the IDLE mode
memory for buffering data.
The 2-4 KB
buffering legacy paging limit is not applicable for HLCOM. In case of HLCOM
devices, upto 4KB data can be buffered per UE in the dedicated 96MB memory.
Those devices for which 4k memory is utilized and more is needed, memory can be
extended upto 10k, provided memory available in the extended memory of size
Important: This feature supports only HLCOM buffering for SAEGW call.
HLCOM support was not there for SAEGW calls.
HLCOM support for SAEGW calls is now added.
Important: Buffering is done per UE. So irrespective of the number of
bearers or PDNs for a session, all the buffering limits such as the suggested
packet count IE sent in DDNAck and 4KB and 10 KB limits are all valid for the
UE as a whole. HLCOM IE's buffer duration and suggested packet count in DDNAck
are honored only for cause EGTP_CAUSE_REQ_ACCEPTED and
EGTP_CAUSE_UNABLE_TO_PAGE_UE. For other causes, these IE's are ignored.