Inter-Asngw Handoff - Cisco ASR 5000 series Product Overview

ASN Gateway Overview

Inter-ASNGW Handoff

For control and data path setup for an inter-ASNGW handoff, the serving base station (SBS) is connected to the anchor
GW and the target base station (TBS) is connected to the non-anchor GW. During INE, the anchor GW specifies a
different IP address for data traffic. For example, if AT1 and DT1 are the data endpoints on the ASNGW and SBS side,
the ASNGW informs the SBS about a different address for data by sending out a tunnel endpoint IP address in the MS
information TLV in the DP-Reg Request during INE.
Similarly, during inter-ASNGW handoff, the non-anchor GW specifies the different data tunnel endpoint for uplink
traffic in the DP-Reg Rsp message. The same address on the non-anchor GW receives the downlink data packets from
the anchor GW. AT2 and DT2 are the data tunnel endpoint for the non-anchor GW and TBS, respectively. The tunnel
endpoint IP address is populated in the MS information TLV in DP Reg Rsp message from non-anchor GW to the TBS.
The non-anchor GW conveys the tunnel endpoint to receive the downlink traffic towards the anchor GW in the DP-Reg
Req message. The anchor GW specifies the tunnel endpoint to receive the uplink traffic in the DP-Reg Rsp message.
AT1 and AT2 are the data tunnel endpoints on the anchor and non-anchor GWs, respectively, to negotiate R6 control
traffic. SB1 and TB1 are the control addresses on the SBS and TBS, respectively.
Intra-ASNGW Handoff
For intra-ASNGW handoff, during INE, the ASNGW specifies the different data tunnel endpoint for receiving uplink
traffic in the DP-Reg Req message to the serving base station (SBS). After handoff, the ASNGW specifies the different
data tunnel endpoint to receive the Uplink traffic in the DP-Reg Rsp message. For example, AT1 is the tunnel endpoint
on ASNGW for data traffic. DT1 and DT2 are the data tunnel endpoints on the SBS and TBS, respectively. The
ASNGW provides the tunnel endpoint in the MS information TLV within the data path messages
AS1 is the control address on the ASNGW to negotiate R6 control traffic. SB1 and TB1 are the control addresses on
SBS and TBS, respectively. The non-ANCHOR GW conveys the tunnel endpoint to receive the downlink traffic
towards the ANCHOR GW in the DP-Reg Req message. The ANCHOR GW specifies the tunnel endpoint to receive the
uplink traffic in the DP-Reg Rsp message. AT1 and AT2 are the data tunnel endpoints on the anchor and non-anchor
GWs, respectively to negotiate R6 control traffic. SB1 and TB1 is the control address on SBS and TBS, respectively.
OL-22938-02
Data Tunnel Endpoint Support ▀
Cisco ASR 5000 Series Product Overview ▄