diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4dbbc98..ab8ed0c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,4 +11,15 @@ _2023-11-14_
_2023-12-26_
-- Restructure code to support different types of plugins
\ No newline at end of file
+- Restructure code to support different types of plugins
+
+_2024_3_27_
+
+- Support OTel environment variables: OTEL_EXPORTER_OTLP_HEADERS & OTEL_EXPORTER_OTLP_CERTIFICATE
+
+_2026-6-27_
+
+- Add SNMP support
+- Sdk vault integration
+
+
diff --git a/README.md b/README.md
index 9f831a0..0127309 100644
--- a/README.md
+++ b/README.md
@@ -1,19 +1,29 @@
-# ODCD (OpenTelemetry Data Collector for Telemetry Data)
+# ODCD (OpenTelemetry Data Collector Divers)
**[Semantic Convention](docs/semconv)** |
-**[Support](docs/support/README.md)** |
**[Changelog](CHANGELOG.md)** |
**[Contributing](CONTRIBUTING.md)** |
**[License](LICENSE)**
---
-ODCD (OpenTelemetry Data Collector for Telemetry Data) is a collection of stanalone OpenTelemetry receivers for databases, systems, and apps. All implementations are based on predefined OpenTelemetry Semantic Conventions. A standard OTLP exporter is provided to forward the data from this "Data Collector" to a Telemetry backend or an OpenTelemetry Collector.
+ODCD (OpenTelemetry Data Collector Divers) is a collection of stanalone OpenTelemetry receivers for databases, systems, apps, ant etc. All implementations are based on predefined OpenTelemetry Semantic Conventions. A standard OTLP exporter is provided to forward the data from this "Data Collector" to a Telemetry backend or an OpenTelemetry Collector.
+
-
-# Data Collectors provided
+## Data Collectors provided
- [OTel Data Collectors for Relational Databases](rdb/README.md) (**Java 8+**)
- [OTel Data Collectors for Host](host/README.md) (**Java 11+**)
- [OTel Data Collectors for LLM](llm/README.md) (**Java 11+**)
+
+## Common Parameters for Data Collectors
+
+| Parameter | Scope | Description | Example |
+|---------------------------|-----------|-----------------------------------------------------------------------------------------------------------------------|------------------------|
+| otel.backend.url | instance | The otlp URL of the OTel Backend. E.g., http://localhost:4317 (grpc) or http://localhost:4318/v1/metrics (http) | http://127.0.0.1:4317 |
+| otel.backend.using.http | instance | false (default, using otlp/grpc) or true (using otlp/http) | false |
+| otel.service.name | instance | The OTel Service name (It is requred by OTel) | DamengDC |
+| otel.service.instance.id | instance | The OTel Service instance ID (which is ID of this database entity. It can be generated by DC if it is not provided) | 1.2.3.4:5236@MYDB |
+| poll.interval | instance | The time interval in seconds to query metrics | 25 |
+| callback.interval | instance | The time interval in seconds to post data to backend | 30 |
diff --git a/docs/developer/new-db.md b/docs/developer/new-db.md
index fe422e2..61752e9 100644
--- a/docs/developer/new-db.md
+++ b/docs/developer/new-db.md
@@ -55,7 +55,7 @@ Here is the list of redefined database and OTel parameters:
| otel.backend.using.http | false (default, using otlp/grpc) or true (using otlp/http) | false |
| otel.service.name | The OTel Service name (It is requred by OTel) | DamengDC |
| otel.service.instance.id | The OTel Service instance ID (which is ID of this database entity. It can be generated by DC if it is not provided) | 1.2.3.4:5236@MYDB |
-| poll.interval | The time interval in seconds to query metrics | 20 |
+| poll.interval | The time interval in seconds to query metrics | 25 |
| callback.interval | The time interval in seconds to post data to backend | 30 |
| db.entity.parent.id | It there is a parent of this entity, set to the otel.service.instance.id of the parent | cluster@OBCluster1 |
diff --git a/host/README.md b/host/README.md
index 6ca4cff..5e7f27a 100644
--- a/host/README.md
+++ b/host/README.md
@@ -1,16 +1,3 @@
-# ODCD (OpenTelemetry Data Collector for Telemetry Data)
-
-**[Semantic Convention](../docs/semconv)** |
-**[Support](../docs/support/README.md)** |
-**[Changelog](../CHANGELOG.md)** |
-**[Contributing](../CONTRIBUTING.md)** |
-**[License](../LICENSE)**
-
----
-ODCD (OpenTelemetry Data Collector for Telemetry Data) is a collection of stanalone OpenTelemetry receivers for databases, systems, and apps. All implementations are based on predefined OpenTelemetry Semantic Conventions. A standard OTLP exporter is provided to forward the data from this "Data Collector" to a Telemetry backend or an OpenTelemetry Collector.
-
-
-
# Data Collector for Hosts
@@ -53,18 +40,33 @@ Refine configuration file (config/config.yaml) according to your host. Right now
export DC_CONFIG=config/config-mqappliance.yaml
```
-Notes for some parameters：
-- `otel.backend.url`：The OTel gRPC address of the OTel backends, for example Instana Agent (as OTel Backend): http://localhost:4317
-- `otel.service.name`：The Data Collector name, which can be any string you choose.
-
4) Run Data Collector
Run the Data Collector with the following command according to your current system:
```bash
nohup ./bin/otel-dc-host
```
-
-## Build & Run (for develpers)
+## Specific Parameters for Host Data Collectors
+
+| Parameter | Scope | Description | Example |
+|--------------------|-----------------------|-----------------------------------------------------------------------------|---------------------------|
+| host.system | global | The engine of this host data collector | snmp_host or mq_appliance |
+| snmp.host | instance/snmp_host | The endpoint of SNMP host | udp:9.112.252.102/161 |
+| host.name | instance/snmp_host | Optional: use this to overwrite the value got by SNMP | stantest0.fyre.ibm.com |
+| os.type | instance/snmp_host | Optional: use this to overwrite the value got by SNMP | linux |
+| community | instance/snmp_host | Optional: The community string (default: public) | public |
+| retries | instance/snmp_host | Optional: times to retry (default: 3) | 3 |
+| timeout | instance/snmp_host | Optional: timesout in ms (default: 450) | 450 |
+| version | instance/snmp_host | Optional: version of SNMP (0:version1, 1:version2c, 3:version3) (default:1) | 1 |
+| securityLevel | instance/snmp_host | Optional: Choose 1:NOAUTH_NOPRIV 2:AUTH_NOPRIV 3:AUTH_PRIV (default: 1) | 3 |
+| authPassword | instance/snmp_host | Optional: Auth password (version 3) (default: "") | password |
+| privacyPassword | instance/snmp_host | Optional: Privacy password (version 3) (default: "") | password |
+| appliance.host | instance/mq_appliance | host name for MQ appliance | testbox1.mqappliance.com |
+| appliance.user | instance/mq_appliance | user name for MQ appliance | admin |
+| appliance.password | instance/mq_appliance | password for MQ appliance | xxxx |
+
+
+## Build & Run (for developers)
1) Make sure Java SDK 11+ is installed.
```bash
diff --git a/rdb/README.md b/rdb/README.md
index 5a0c756..d52eb40 100644
--- a/rdb/README.md
+++ b/rdb/README.md
@@ -1,16 +1,3 @@
-# ODCD (OpenTelemetry Data Collector for Telemetry Data)
-
-**[Semantic Convention](docs/semconv)** |
-**[Support](docs/support/README.md)** |
-**[Changelog](CHANGELOG.md)** |
-**[Contributing](CONTRIBUTING.md)** |
-**[License](LICENSE)**
-
----
-ODCD (OpenTelemetry Data Collector for Telemetry Data) is a collection of stanalone OpenTelemetry receivers for databases, systems, and apps. All implementations are based on predefined OpenTelemetry Semantic Conventions. A standard OTLP exporter is provided to forward the data from this "Data Collector" to a Telemetry backend or an OpenTelemetry Collector.
-
-
-
# Data Collector for Relational Database
@@ -63,7 +50,7 @@ nohup ./bin/otel-dc-rdb
```
-## Build & Run (for develpers)
+## Build & Run (for developers)
1) Make sure Java SDK is installed.
```bash