Control Slice Customized SM

Overview

A slice control xApp, utilizing the custom service model SLICE SM, is developed to manage and control slices within E2-Nodes. It offers support for three distinct action types: 1) adding/modifying slices, 2) associating UE's slice, and 3) deleting slices. This enables the creation of tailored slice control messages by populating various parameters with the appropriate slicing algorithm.

It includes the following stages:

• Init: initializes xApp based on configuration to set up the E42 connection with NearRT-RIC
• xApp Logic: creates customized control message
• Control Service: sends control request to each E2-Node
• Exit: terminates xApp

Sequence Diagram

Detail

source code: xapp_slice_ctrl.py

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Init - Step 2 to 5

• Used Functions
  • init()
  • conn_e2_nodes()

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xApp Logic - Step 6

Develop your xApp logic to generate the customized control message based on the given action type. For example, utilize the function fill_slice_ctrl_msg() below to generate a customized control message, filling the necessary parameters according to the slice_ctrl_msg_t structure.

fill_slice_ctrl_msg()

• Input

  Parameter	Type in Python	Comment
  act_type	string	Action types of slice (e.g., ADDMOD, ASSOC_UE_SLICE, and DEL)
  param	json	Required parameters to create customized control message

Note: Different action types require specific input parameters. For instance, ADDMOD uses the slice_conf_t structure, ASSOC_UE_SLICE utilizes the ue_slice_conf_t structure, and DEL is based on the del_slice_conf_t structure.

• Output

  Parameter	Type in Python	Type in Swig Wrapper C++	Comment
  msg	xapp_sdk.slice_ctrl_msg_t	slice_ctrl_msg_t	Control message using SLICE SM

• Example - Add/Modify Slice

# Define action type
act_type = "ADDMOD"

# Define required parameters based on slice_conf_t
add_slice_parameters_json = {
    "num_slices" : 2,
    "slice_sched_algo" : "NVS",
    "slices" : [
        {
            "id" : 0,
            "label" : "s1",
            "ue_sched_algo" : "PF",
            "type" : "SLICE_SM_NVS_V0_CAPACITY",
            "slice_algo_params" : {"pct_rsvd" : 0.7},
        },
        {
            "id" : 2,
            "label" : "s2",
            "ue_sched_algo" : "PF",
            "type" : "SLICE_SM_NVS_V0_CAPACITY",
            "slice_algo_params" : {"pct_rsvd" : 0.3},
        }
    ]
}

# Generate control message
msg = fill_slice_ctrl_msg(act_type, add_slice_parameters_json)

• Example - Associate UE's Slice

# Define action type
act_type = "ASSPC_UE_SLICE"

# Define required parameters based on ue_slice_conf_t
assoc_slice_parameter_json = {
    "num_ues" : 1,
    "ues" : [
        {
            "rnti" : 0x1234,
            "assoc_dl_slice_id" : 2
        }
    ]
}

# Generate control message
msg = fill_slice_ctrl_msg(act_type, assoc_slice_parameter_json)

• Example - Delete Slice

# Define action type
act_type = "DEL"

# Define required parameters based on del_slice_conf_t
delete_slice_parameter_json = {
    "num_dl_slices" : 1,
    "delete_dl_slice_id" : [2]
}

# Generate control message
msg = fill_slice_ctrl_msg(act_type, delete_slice_parameter_json)

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Control Service - Step 7 to 11

• Used function
  • control_{SM-NAME}_sm()

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Exit - Step 12

• Used function
  • try_stop()