User's Manual

Chapter 3 - Operation and Administration Using the CLI Managing BSs
4Motion 628 System Manual
The BS builds a list of ASN-GW-of-Interest, which it must poll. The list is
dynamically updated; when a new MS is attached to the BS, or MS performs CSN
mobility (data-path relocation) and in its context there is an ASN-GW identifier
unknown to this BS, it shall add it to the ASN-GW-of-interest list. When the last
MS(s) with specific ASN-GW identifier exits the network, the BS shall remove the
ASN-GW from the list. The BS shall include in the ASN-GW-of-interest list also
Relay Data-path ASN-GW(s) (UL next hop IP address). This is applicable when
hierarchical data-path establishment takes place during inter-ASN HO.
The BS periodically polls the ASN-GW(s) for keep-alive. The polling mechanism is
independent and unrelated for every ASN-GW-of-interest the BS polls.
The keep-alive mechanism uses configurable retry timer and retries counter.
Upon expiration of the retry timer, the BS resends the BS Keep-Alive request
message. Upon expiration of the retries counter, the BS assumes failure of the
polled ASN-GW and clears the contexts of all MS(s) served by that ASN-GW.
In addition, the BS verifies that for each polled entity that the “Last-Reset-Time”
UTC value of poll N+1 is equal to the value of poll N. If the “Last-Reset-Time” UTC
value of poll N+1 is higher than the value of poll N, this mean that the ASN-GW
went through reset state during the interval between two consecutive polls. In this
case, the BS shall de-register all MS(s) served by that specific ASN-GW and clear
their contexts.
When keep-alive fails, the BS generates an alarm and log the event.
Regardless of the enable/disable status of the keep-alive mechanism in the BS, it
replies to BS_Keep_Alive_Req received from ASN-GWs with BS_Keep_Alive_Rsp.
that includes also its “Last-Reset-Time”. It responds only if all its functions
operate properly. In case one of the functions fails, the BS shall not respond to the
keep-alive poll.
3.8.26.1 Configuring BS Keep-Alive Parameters
To configure one or several keep-alive parameters, run the following command:
npu(config-bs-66053)# keep-alive [asn-ka {enable | disable} ] [period <(10 to
1000 StepSize 1)> ] [rtx-cnt <(0 to 10 StepSize 1)> ] [rtx-time <(100 to 10000
StepSize 1)> ]
IMPORTANT
An error may occur if you provide configuration values that do not satisfy following condition:
'period*1000 >= rtx-time * (rtx-cnt + 1)'"